Skip CancelAllBackgroundWork if DBImpl is already closed (#6268 )

Summary: WritePreparedTxnDB calls CancelAllBackgroundWork in its destructor to avoid dangling references to it from background job's SnapshotChecker callback. However, if the DBImpl is already closed, the info log might be closed with it, which causes memory leak when CancelAllBackgroundWork tries to print to the info log. The patch fixes that by calling CancelAllBackgroundWork only if the db is not closed already. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6268 Differential Revision: D19303439 Pulled By: maysamyabandeh fbshipit-source-id: 4228a6be7e78d43c90630347baa89b008200bd15
parallel occ (#6240 )
2026-11-06 02:52:35 -05:00 · 2020-01-07 15:34:27 -08:00 · 2020-01-07 14:20:38 -08:00 · 2020-01-07 13:56:13 -08:00 · 2020-01-07 13:47:03 -08:00 · 2020-01-07 12:32:20 -08:00
658 changed files with 57875 additions and 20952 deletions
@@ -79,3 +79,4 @@ tp2/
 fbcode/
 fbcode
 buckifier/*.pyc
+buckifier/__pycache__
@@ -6,25 +6,34 @@ os:
 compiler:
  - clang
  - gcc
-osx_image: xcode8.3
+osx_image: xcode9.4
 jdk:
  - openjdk7
 cache:
  - ccache
-  - apt

 addons:
  apt:
    sources:
      - ubuntu-toolchain-r-test
    packages:
-      - curl
-      - g++-8
-      - libbz2-dev
      - libgflags-dev
+      - libbz2-dev
+      - liblz4-dev
      - libsnappy-dev
-      - mingw-w64
+      - liblzma-dev  # xv
+      - libzstd-dev
      - zlib1g-dev
+  homebrew:
+    update: true
+    packages:
+      - ccache
+      - gflags
+      - lz4
+      - snappy
+      - xz
+      - zstd
+
 env:
  - TEST_GROUP=platform_dependent # 16-18 minutes
  - TEST_GROUP=1 # 33-35 minutes
@@ -60,15 +69,17 @@ matrix:
  - os : osx
    compiler: gcc

-# https://docs.travis-ci.com/user/caching/#ccache-cache
 install:
  - if [ "${TRAVIS_OS_NAME}" == osx ]; then
-      brew install ccache zstd lz4 snappy xz;
      PATH=$PATH:/usr/local/opt/ccache/libexec;
    fi
  - if [ "${JOB_NAME}" == cmake-gcc8 ]; then
+      sudo apt-get install -y g++-8;
      CC=gcc-8 && CXX=g++-8;
    fi
+  - if [ "${JOB_NAME}" == cmake-mingw ]; then
+      sudo apt-get install -y mingw-w64 ;
+    fi
  - if [[ "${JOB_NAME}" == cmake* ]] && [ "${TRAVIS_OS_NAME}" == linux ]; then
      mkdir cmake-dist && curl -sfSL https://github.com/Kitware/CMake/releases/download/v3.14.5/cmake-3.14.5-Linux-x86_64.tar.gz | tar --strip-components=1 -C cmake-dist -xz && export PATH=$PWD/cmake-dist/bin:$PATH;
    fi
@@ -89,13 +100,13 @@ script:
      OPT=-DTRAVIS V=1 ROCKSDBTESTS_END=db_block_cache_test make -j4 all_but_some_tests check_some
      ;;
    1)
-      OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=db_block_cache_test ROCKSDBTESTS_END=full_filter_block_test make -j4 check_some
+      OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=db_block_cache_test ROCKSDBTESTS_END=db_iter_test make -j4 check_some
      ;;
    2)
-      OPT=-DTRAVIS V=1 make -j4 tools && OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=full_filter_block_test ROCKSDBTESTS_END=write_batch_with_index_test make -j4 check_some
+      OPT=-DTRAVIS V=1 make -j4 tools && OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=db_iter_test ROCKSDBTESTS_END=options_file_test make -j4 check_some
      ;;
    3)
-      OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=write_batch_with_index_test ROCKSDBTESTS_END=write_prepared_transaction_test make -j4 check_some
+      OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=options_file_test ROCKSDBTESTS_END=write_prepared_transaction_test make -j4 check_some
      ;;
    4)
      OPT=-DTRAVIS V=1 ROCKSDBTESTS_START=write_prepared_transaction_test make -j4 check_some
@@ -113,7 +124,7 @@ script:
      ;;
    cmake-mingw)
      sudo update-alternatives --set x86_64-w64-mingw32-g++ /usr/bin/x86_64-w64-mingw32-g++-posix;
-      mkdir build && cd build && cmake -DJNI=1 .. -DCMAKE_C_COMPILER=x86_64-w64-mingw32-gcc -DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-g++ -DCMAKE_SYSTEM_NAME=Windows && make -j4 rocksdb rocksdbjni
+      mkdir build && cd build && cmake -DJNI=1 -DWITH_GFLAGS=OFF .. -DCMAKE_C_COMPILER=x86_64-w64-mingw32-gcc -DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-g++ -DCMAKE_SYSTEM_NAME=Windows && make -j4 rocksdb rocksdbjni
      ;;
    cmake*)
      mkdir build && cd build && cmake -DJNI=1 .. -DCMAKE_BUILD_TYPE=Release && make -j4 rocksdb rocksdbjni
@@ -122,5 +133,3 @@ script:
 notifications:
    email:
      - leveldb@fb.com
-    webhooks:
-      - https://buildtimetrend.herokuapp.com/travis
@@ -14,7 +14,7 @@
 #        cd build
 # 3. Run cmake to generate project files for Windows, add more options to enable required third-party libraries.
 #    See thirdparty.inc for more information.
-#        sample command: cmake -G "Visual Studio 15 Win64" -DWITH_GFLAGS=1 -DWITH_SNAPPY=1 -DWITH_JEMALLOC=1 -DWITH_JNI=1 ..
+#        sample command: cmake -G "Visual Studio 15 Win64" -DCMAKE_BUILD_TYPE=Release -DWITH_GFLAGS=1 -DWITH_SNAPPY=1 -DWITH_JEMALLOC=1 -DWITH_JNI=1 ..
 # 4. Then build the project in debug mode (you may want to add /m[:<N>] flag to run msbuild in <N> parallel threads
 #                                          or simply /m to use all avail cores)
 #        msbuild rocksdb.sln
@@ -32,17 +32,28 @@
 # 3. cmake ..
 # 4. make -j

-cmake_minimum_required(VERSION 2.8.12)
-project(rocksdb)
-enable_language(CXX)
-enable_language(C)
-enable_language(ASM)
+cmake_minimum_required(VERSION 3.5.1)
+
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake/modules/")
+include(ReadVersion)
+get_rocksdb_version(rocksdb_VERSION)
+project(rocksdb
+  VERSION ${rocksdb_VERSION}
+  LANGUAGES CXX C ASM)

 if(POLICY CMP0042)
  cmake_policy(SET CMP0042 NEW)
 endif()

-list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake/modules/")
+if(NOT CMAKE_BUILD_TYPE)
+  if(EXISTS "${CMAKE_SOURCE_DIR}/.git")
+    set(default_build_type "Debug")
+  else()
+    set(default_build_type "RelWithDebInfo")
+  endif()
+  set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE STRING
+    "Default BUILD_TYPE is ${default_build_type}" FORCE)
+endif()

 find_program(CCACHE_FOUND ccache)
 if(CCACHE_FOUND)
@@ -59,10 +70,24 @@ option(WITH_WINDOWS_UTF8_FILENAMES "use UTF8 as characterset for opening files,
 if (WITH_WINDOWS_UTF8_FILENAMES)
  add_definitions(-DROCKSDB_WINDOWS_UTF8_FILENAMES)
 endif()
+# third-party/folly is only validated to work on Linux and Windows for now.
+# So only turn it on there by default.
+if(CMAKE_SYSTEM_NAME MATCHES "Linux|Windows")
+  if(MSVC AND MSVC_VERSION LESS 1910)
+    # Folly does not compile with MSVC older than VS2017
+    option(WITH_FOLLY_DISTRIBUTED_MUTEX "build with folly::DistributedMutex" OFF)
+  else()
+    option(WITH_FOLLY_DISTRIBUTED_MUTEX "build with folly::DistributedMutex" ON)
+  endif()
+else()
+  option(WITH_FOLLY_DISTRIBUTED_MUTEX "build with folly::DistributedMutex" OFF)
+endif()
+
+include(CMakeDependentOption)
+CMAKE_DEPENDENT_OPTION(WITH_GFLAGS "build with GFlags" ON
+  "NOT MSVC;NOT MINGW" OFF)
+
 if(MSVC)
-  # Defaults currently different for GFLAGS.
-  #  We will address find_package work a little later
-  option(WITH_GFLAGS "build with GFlags" OFF)
  option(WITH_XPRESS "build with windows built in compression" OFF)
  include(${CMAKE_CURRENT_SOURCE_DIR}/thirdparty.inc)
 else()
@@ -74,66 +99,58 @@ else()
    if(WITH_JEMALLOC)
      find_package(JeMalloc REQUIRED)
      add_definitions(-DROCKSDB_JEMALLOC -DJEMALLOC_NO_DEMANGLE)
-      include_directories(${JEMALLOC_INCLUDE_DIR})
-      list(APPEND THIRDPARTY_LIBS ${JEMALLOC_LIBRARIES})
+      list(APPEND THIRDPARTY_LIBS JeMalloc::JeMalloc)
    endif()
  endif()

  # No config file for this
-  option(WITH_GFLAGS "build with GFlags" ON)
  if(WITH_GFLAGS)
-    find_package(gflags)
-    if(gflags_FOUND)
-      add_definitions(-DGFLAGS=1)
-      include_directories(${gflags_INCLUDE_DIR})
-      list(APPEND THIRDPARTY_LIBS ${gflags_LIBRARIES})
-    endif()
+    find_package(gflags REQUIRED)
+    add_definitions(-DGFLAGS=1)
+    include_directories(${gflags_INCLUDE_DIR})
+    list(APPEND THIRDPARTY_LIBS gflags::gflags)
  endif()

  if(WITH_SNAPPY)
    find_package(snappy REQUIRED)
    add_definitions(-DSNAPPY)
-    include_directories(${SNAPPY_INCLUDE_DIR})
-    list(APPEND THIRDPARTY_LIBS ${SNAPPY_LIBRARIES})
+    list(APPEND THIRDPARTY_LIBS snappy::snappy)
  endif()

  if(WITH_ZLIB)
    find_package(ZLIB REQUIRED)
    add_definitions(-DZLIB)
-    if(ZLIB_INCLUDE_DIRS)
-      # CMake 3
-      include_directories(${ZLIB_INCLUDE_DIRS})
-    else()
-      # CMake 2
-      include_directories(${ZLIB_INCLUDE_DIR})
-    endif()
-    list(APPEND THIRDPARTY_LIBS ${ZLIB_LIBRARIES})
+    list(APPEND THIRDPARTY_LIBS ZLIB::ZLIB)
  endif()

  option(WITH_BZ2 "build with bzip2" OFF)
  if(WITH_BZ2)
-    find_package(bzip2 REQUIRED)
+    find_package(BZip2 REQUIRED)
    add_definitions(-DBZIP2)
-    include_directories(${BZIP2_INCLUDE_DIR})
+    if(BZIP2_INCLUDE_DIRS)
+      include_directories(${BZIP2_INCLUDE_DIRS})
+    else()
+      include_directories(${BZIP2_INCLUDE_DIR})
+    endif()
    list(APPEND THIRDPARTY_LIBS ${BZIP2_LIBRARIES})
  endif()

  if(WITH_LZ4)
    find_package(lz4 REQUIRED)
    add_definitions(-DLZ4)
-    include_directories(${LZ4_INCLUDE_DIR})
-    list(APPEND THIRDPARTY_LIBS ${LZ4_LIBRARIES})
+    list(APPEND THIRDPARTY_LIBS lz4::lz4)
  endif()

  if(WITH_ZSTD)
    find_package(zstd REQUIRED)
    add_definitions(-DZSTD)
    include_directories(${ZSTD_INCLUDE_DIR})
-    list(APPEND THIRDPARTY_LIBS ${ZSTD_LIBRARIES})
+    list(APPEND THIRDPARTY_LIBS zstd::zstd)
  endif()
 endif()

-string(TIMESTAMP GIT_DATE_TIME "%Y/%m/%d %H:%M:%S" UTC)
+string(TIMESTAMP TS "%Y/%m/%d %H:%M:%S" UTC)
+set(GIT_DATE_TIME "${TS}" CACHE STRING "the time we first built rocksdb")

 find_package(Git)

@@ -150,17 +167,6 @@ endif()
 string(REGEX REPLACE "[^0-9a-f]+" "" GIT_SHA "${GIT_SHA}")


-# Read rocksdb version from version.h header file.
-file(READ include/rocksdb/version.h version_header_file)
-string(REGEX MATCH "#define ROCKSDB_MAJOR ([0-9]+)" _ ${version_header_file})
-set(ROCKSDB_VERSION_MAJOR ${CMAKE_MATCH_1})
-string(REGEX MATCH "#define ROCKSDB_MINOR ([0-9]+)" _ ${version_header_file})
-set(ROCKSDB_VERSION_MINOR ${CMAKE_MATCH_1})
-string(REGEX MATCH "#define ROCKSDB_PATCH ([0-9]+)" _ ${version_header_file})
-set(ROCKSDB_VERSION_PATCH ${CMAKE_MATCH_1})
-set(ROCKSDB_VERSION ${ROCKSDB_VERSION_MAJOR}.${ROCKSDB_VERSION_MINOR}.${ROCKSDB_VERSION_PATCH})
-
-
 option(WITH_MD_LIBRARY "build with MD" ON)
 if(WIN32 AND MSVC)
  if(WITH_MD_LIBRARY)
@@ -182,7 +188,7 @@ else()
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -W -Wextra -Wall")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wsign-compare -Wshadow -Wno-unused-parameter -Wno-unused-variable -Woverloaded-virtual -Wnon-virtual-dtor -Wno-missing-field-initializers -Wno-strict-aliasing")
  if(MINGW)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-format")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-format -fno-asynchronous-unwind-tables")
    add_definitions(-D_POSIX_C_SOURCE=1)
  endif()
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
@@ -209,11 +215,11 @@ if(CMAKE_SYSTEM_PROCESSOR MATCHES "ppc64le")
 endif(CMAKE_SYSTEM_PROCESSOR MATCHES "ppc64le")

 if(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64")
-        CHECK_C_COMPILER_FLAG("-march=armv8-a+crc" HAS_ARMV8_CRC)
+        CHECK_C_COMPILER_FLAG("-march=armv8-a+crc+crypto" HAS_ARMV8_CRC)
  if(HAS_ARMV8_CRC)
    message(STATUS " HAS_ARMV8_CRC yes")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv8-a+crc -Wno-unused-function")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=armv8-a+crc -Wno-unused-function")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=armv8-a+crc+crypto -Wno-unused-function")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=armv8-a+crc+crypto -Wno-unused-function")
  endif(HAS_ARMV8_CRC)
 endif(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64")

@@ -316,15 +322,14 @@ if(WITH_NUMA)
  find_package(NUMA REQUIRED)
  add_definitions(-DNUMA)
  include_directories(${NUMA_INCLUDE_DIR})
-  list(APPEND THIRDPARTY_LIBS ${NUMA_LIBRARIES})
+  list(APPEND THIRDPARTY_LIBS NUMA::NUMA)
 endif()

 option(WITH_TBB "build with Threading Building Blocks (TBB)" OFF)
 if(WITH_TBB)
  find_package(TBB REQUIRED)
  add_definitions(-DTBB)
-  include_directories(${TBB_INCLUDE_DIR})
-  list(APPEND THIRDPARTY_LIBS ${TBB_LIBRARIES})
+  list(APPEND THIRDPARTY_LIBS TBB::TBB)
 endif()

 # Stall notifications eat some performance from inserts
@@ -478,7 +483,10 @@ endif()

 include_directories(${PROJECT_SOURCE_DIR})
 include_directories(${PROJECT_SOURCE_DIR}/include)
-include_directories(SYSTEM ${PROJECT_SOURCE_DIR}/third-party/gtest-1.7.0/fused-src)
+include_directories(SYSTEM ${PROJECT_SOURCE_DIR}/third-party/gtest-1.8.1/fused-src)
+if(WITH_FOLLY_DISTRIBUTED_MUTEX)
+  include_directories(${PROJECT_SOURCE_DIR}/third-party/folly)
+endif()
 find_package(Threads REQUIRED)

 # Main library source code
@@ -487,6 +495,7 @@ set(SOURCES
        cache/clock_cache.cc
        cache/lru_cache.cc
        cache/sharded_cache.cc
+        db/arena_wrapped_db_iter.cc
        db/builder.cc
        db/c.cc
        db/column_family.cc
@@ -537,6 +546,7 @@ set(SOURCES
        db/table_cache.cc
        db/table_properties_collector.cc
        db/transaction_log_impl.cc
+        db/trim_history_scheduler.cc
        db/version_builder.cc
        db/version_edit.cc
        db/version_set.cc
@@ -549,11 +559,18 @@ set(SOURCES
        env/env_chroot.cc
        env/env_encryption.cc
        env/env_hdfs.cc
+        env/file_system.cc
        env/mock_env.cc
        file/delete_scheduler.cc
+        file/file_prefetch_buffer.cc
        file/file_util.cc
        file/filename.cc
+        file/random_access_file_reader.cc
+        file/read_write_util.cc
+        file/readahead_raf.cc
+        file/sequence_file_reader.cc
        file/sst_file_manager_impl.cc
+        file/writable_file_writer.cc
        logging/auto_roll_logger.cc
        logging/event_logger.cc
        logging/log_buffer.cc
@@ -597,13 +614,14 @@ set(SOURCES
        table/block_based/data_block_hash_index.cc
        table/block_based/data_block_footer.cc
        table/block_based/filter_block_reader_common.cc
+        table/block_based/filter_policy.cc
        table/block_based/flush_block_policy.cc
        table/block_based/full_filter_block.cc
        table/block_based/index_builder.cc
+        table/block_based/parsed_full_filter_block.cc
        table/block_based/partitioned_filter_block.cc
        table/block_based/uncompression_dict_reader.cc
        table/block_fetcher.cc
-        table/bloom_block.cc
        table/cuckoo/cuckoo_table_builder.cc
        table/cuckoo/cuckoo_table_factory.cc
        table/cuckoo/cuckoo_table_reader.cc
@@ -613,6 +631,7 @@ set(SOURCES
        table/merging_iterator.cc
        table/meta_blocks.cc
        table/persistent_cache_helper.cc
+        table/plain/plain_table_bloom.cc
        table/plain/plain_table_builder.cc
        table/plain/plain_table_factory.cc
        table/plain/plain_table_index.cc
@@ -627,7 +646,6 @@ set(SOURCES
        test_util/testutil.cc
        test_util/transaction_test_util.cc
        tools/block_cache_analyzer/block_cache_trace_analyzer.cc
-        tools/db_bench_tool.cc
        tools/dump/db_dump_tool.cc
        tools/ldb_cmd.cc
        tools/ldb_tool.cc
@@ -635,7 +653,6 @@ set(SOURCES
        tools/trace_analyzer_tool.cc
        trace_replay/trace_replay.cc
        trace_replay/block_cache_tracer.cc
-        util/bloom.cc
        util/coding.cc
        util/compaction_job_stats_impl.cc
        util/comparator.cc
@@ -643,8 +660,6 @@ set(SOURCES
        util/concurrent_task_limiter_impl.cc
        util/crc32c.cc
        util/dynamic_bloom.cc
-        util/file_reader_writer.cc
-        util/filter_policy.cc
        util/hash.cc
        util/murmurhash.cc
        util/random.cc
@@ -678,6 +693,7 @@ set(SOURCES
        utilities/merge_operators/bytesxor.cc
        utilities/merge_operators/max.cc
        utilities/merge_operators/put.cc
+        utilities/merge_operators/sortlist.cc
        utilities/merge_operators/string_append/stringappend.cc
        utilities/merge_operators/string_append/stringappend2.cc
        utilities/merge_operators/uint64add.cc
@@ -751,12 +767,23 @@ else()
  list(APPEND SOURCES
    port/port_posix.cc
    env/env_posix.cc
+    env/fs_posix.cc
    env/io_posix.cc)
 endif()

+if(WITH_FOLLY_DISTRIBUTED_MUTEX)
+  list(APPEND SOURCES
+    third-party/folly/folly/detail/Futex.cpp
+    third-party/folly/folly/synchronization/AtomicNotification.cpp
+    third-party/folly/folly/synchronization/DistributedMutex.cpp
+    third-party/folly/folly/synchronization/ParkingLot.cpp
+    third-party/folly/folly/synchronization/WaitOptions.cpp)
+endif()
+
 set(ROCKSDB_STATIC_LIB rocksdb${ARTIFACT_SUFFIX})
 set(ROCKSDB_SHARED_LIB rocksdb-shared${ARTIFACT_SUFFIX})
-set(ROCKSDB_IMPORT_LIB ${ROCKSDB_SHARED_LIB})
+
+option(ROCKSDB_BUILD_SHARED "Build shared versions of the RocksDB libraries" ON)

 option(WITH_LIBRADOS "Build with librados" OFF)
 if(WITH_LIBRADOS)
@@ -766,41 +793,45 @@ if(WITH_LIBRADOS)
 endif()

 if(WIN32)
-  set(SYSTEM_LIBS ${SYSTEM_LIBS} Shlwapi.lib Rpcrt4.lib)
-  set(LIBS ${ROCKSDB_STATIC_LIB} ${THIRDPARTY_LIBS} ${SYSTEM_LIBS})
+  set(SYSTEM_LIBS ${SYSTEM_LIBS} shlwapi.lib rpcrt4.lib)
 else()
  set(SYSTEM_LIBS ${CMAKE_THREAD_LIBS_INIT})
-  set(LIBS ${ROCKSDB_SHARED_LIB} ${THIRDPARTY_LIBS} ${SYSTEM_LIBS})
-
-  add_library(${ROCKSDB_SHARED_LIB} SHARED ${SOURCES})
-  target_link_libraries(${ROCKSDB_SHARED_LIB}
-    ${THIRDPARTY_LIBS} ${SYSTEM_LIBS})
-  set_target_properties(${ROCKSDB_SHARED_LIB} PROPERTIES
-                        LINKER_LANGUAGE CXX
-                        VERSION ${ROCKSDB_VERSION}
-                        SOVERSION ${ROCKSDB_VERSION_MAJOR}
-                        CXX_STANDARD 11
-                        OUTPUT_NAME "rocksdb")
 endif()

 add_library(${ROCKSDB_STATIC_LIB} STATIC ${SOURCES})
 target_link_libraries(${ROCKSDB_STATIC_LIB}
  ${THIRDPARTY_LIBS} ${SYSTEM_LIBS})

-if(WIN32)
-  add_library(${ROCKSDB_IMPORT_LIB} SHARED ${SOURCES})
-  target_link_libraries(${ROCKSDB_IMPORT_LIB}
+if(ROCKSDB_BUILD_SHARED)
+  add_library(${ROCKSDB_SHARED_LIB} SHARED ${SOURCES})
+  target_link_libraries(${ROCKSDB_SHARED_LIB}
    ${THIRDPARTY_LIBS} ${SYSTEM_LIBS})
-  set_target_properties(${ROCKSDB_IMPORT_LIB} PROPERTIES
-    COMPILE_DEFINITIONS "ROCKSDB_DLL;ROCKSDB_LIBRARY_EXPORTS")
-  if(MSVC)
-    set_target_properties(${ROCKSDB_STATIC_LIB} PROPERTIES
-      COMPILE_FLAGS "/Fd${CMAKE_CFG_INTDIR}/${ROCKSDB_STATIC_LIB}.pdb")
-    set_target_properties(${ROCKSDB_IMPORT_LIB} PROPERTIES
-      COMPILE_FLAGS "/Fd${CMAKE_CFG_INTDIR}/${ROCKSDB_IMPORT_LIB}.pdb")
+
+  if(WIN32)
+    set_target_properties(${ROCKSDB_SHARED_LIB} PROPERTIES
+      COMPILE_DEFINITIONS "ROCKSDB_DLL;ROCKSDB_LIBRARY_EXPORTS")
+    if(MSVC)
+      set_target_properties(${ROCKSDB_STATIC_LIB} PROPERTIES
+        COMPILE_FLAGS "/Fd${CMAKE_CFG_INTDIR}/${ROCKSDB_STATIC_LIB}.pdb")
+      set_target_properties(${ROCKSDB_SHARED_LIB} PROPERTIES
+        COMPILE_FLAGS "/Fd${CMAKE_CFG_INTDIR}/${ROCKSDB_SHARED_LIB}.pdb")
+    endif()
+  else()
+    set_target_properties(${ROCKSDB_SHARED_LIB} PROPERTIES
+                          LINKER_LANGUAGE CXX
+                          VERSION ${rocksdb_VERSION}
+                          SOVERSION ${rocksdb_VERSION_MAJOR}
+                          CXX_STANDARD 11
+                          OUTPUT_NAME "rocksdb")
  endif()
 endif()

+if(ROCKSDB_BUILD_SHARED AND NOT WIN32)
+  set(ROCKSDB_LIB ${ROCKSDB_SHARED_LIB})
+else()
+  set(ROCKSDB_LIB ${ROCKSDB_STATIC_LIB})
+endif()
+
 option(WITH_JNI "build with JNI" OFF)
 if(WITH_JNI OR JNI)
  message(STATUS "JNI library is enabled")
@@ -833,7 +864,7 @@ if(NOT WIN32 OR ROCKSDB_INSTALL_ON_WINDOWS)

  write_basic_package_version_file(
    RocksDBConfigVersion.cmake
-    VERSION ${ROCKSDB_VERSION}
+    VERSION ${rocksdb_VERSION}
    COMPATIBILITY SameMajorVersion
  )

@@ -847,15 +878,17 @@ if(NOT WIN32 OR ROCKSDB_INSTALL_ON_WINDOWS)
    INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
  )

-  install(
-    TARGETS ${ROCKSDB_SHARED_LIB}
-    EXPORT RocksDBTargets
-    COMPONENT runtime
-    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-    RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
-    LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-    INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
-  )
+  if(ROCKSDB_BUILD_SHARED)
+    install(
+      TARGETS ${ROCKSDB_SHARED_LIB}
+      EXPORT RocksDBTargets
+      COMPONENT runtime
+      ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+      RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
+      LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+      INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+    )
+  endif()

  install(
    EXPORT RocksDBTargets
@@ -873,9 +906,15 @@ if(NOT WIN32 OR ROCKSDB_INSTALL_ON_WINDOWS)
  )
 endif()

-option(WITH_TESTS "build with tests" ON)
+add_subdirectory(third-party/gtest-1.8.1/fused-src/gtest)
+add_library(testharness STATIC
+  test_util/testharness.cc)
+target_link_libraries(testharness gtest)
+
+# Tests are excluded from Release builds
+CMAKE_DEPENDENT_OPTION(WITH_TESTS "build with tests" ON
+  "CMAKE_BUILD_TYPE STREQUAL Debug" OFF)
 if(WITH_TESTS)
-  add_subdirectory(third-party/gtest-1.7.0/fused-src/gtest)
  set(TESTS
        cache/cache_test.cc
        cache/lru_cache_test.cc
@@ -904,6 +943,7 @@ if(WITH_TESTS)
        db/db_log_iter_test.cc
        db/db_memtable_test.cc
        db/db_merge_operator_test.cc
+        db/db_merge_operand_test.cc
        db/db_options_test.cc
        db/db_properties_test.cc
        db/db_range_del_test.cc
@@ -990,6 +1030,7 @@ if(WITH_TESTS)
        util/filelock_test.cc
        util/hash_test.cc
        util/heap_test.cc
+        util/random_test.cc
        util/rate_limiter_test.cc
        util/repeatable_thread_test.cc
        util/slice_transform_test.cc
@@ -1024,23 +1065,10 @@ if(WITH_TESTS)
    list(APPEND TESTS utilities/env_librados_test.cc)
  endif()

-  set(BENCHMARKS
-    cache/cache_bench.cc
-    memtable/memtablerep_bench.cc
-    db/range_del_aggregator_bench.cc
-    tools/db_bench.cc
-    table/table_reader_bench.cc
-    utilities/persistent_cache/hash_table_bench.cc)
-  add_library(testharness OBJECT test_util/testharness.cc)
-  foreach(sourcefile ${BENCHMARKS})
-    get_filename_component(exename ${sourcefile} NAME_WE)
-    add_executable(${exename}${ARTIFACT_SUFFIX} ${sourcefile}
-      $<TARGET_OBJECTS:testharness>)
-    target_link_libraries(${exename}${ARTIFACT_SUFFIX} gtest ${LIBS})
-  endforeach(sourcefile ${BENCHMARKS})
+  if(WITH_FOLLY_DISTRIBUTED_MUTEX)
+    list(APPEND TESTS third-party/folly/folly/synchronization/test/DistributedMutexTest.cpp)
+  endif()

-  # For test util library that is build only in DEBUG mode
-  # and linked to tests. Add test only code that is not #ifdefed for Release here.
  set(TESTUTIL_SOURCE
      db/db_test_util.cc
      monitoring/thread_status_updater_debug.cc
@@ -1048,11 +1076,11 @@ if(WITH_TESTS)
      test_util/fault_injection_test_env.cc
      utilities/cassandra/test_utils.cc
  )
-  # test utilities are only build in debug
  enable_testing()
  add_custom_target(check COMMAND ${CMAKE_CTEST_COMMAND})
  set(TESTUTILLIB testutillib${ARTIFACT_SUFFIX})
  add_library(${TESTUTILLIB} STATIC ${TESTUTIL_SOURCE})
+  target_link_libraries(${TESTUTILLIB} ${ROCKSDB_LIB})
  if(MSVC)
    set_target_properties(${TESTUTILLIB} PROPERTIES COMPILE_FLAGS "/Fd${CMAKE_CFG_INTDIR}/testutillib${ARTIFACT_SUFFIX}.pdb")
  endif()
@@ -1062,46 +1090,86 @@ if(WITH_TESTS)
        EXCLUDE_FROM_DEFAULT_BUILD_RELWITHDEBINFO 1
        )

-  # Tests are excluded from Release builds
-  set(TEST_EXES ${TESTS})
-
-  foreach(sourcefile ${TEST_EXES})
+  foreach(sourcefile ${TESTS})
      get_filename_component(exename ${sourcefile} NAME_WE)
-      add_executable(${CMAKE_PROJECT_NAME}_${exename}${ARTIFACT_SUFFIX} ${sourcefile}
-        $<TARGET_OBJECTS:testharness>)
+      add_executable(${CMAKE_PROJECT_NAME}_${exename}${ARTIFACT_SUFFIX} ${sourcefile})
      set_target_properties(${CMAKE_PROJECT_NAME}_${exename}${ARTIFACT_SUFFIX}
        PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD_RELEASE 1
        EXCLUDE_FROM_DEFAULT_BUILD_MINRELEASE 1
        EXCLUDE_FROM_DEFAULT_BUILD_RELWITHDEBINFO 1
        OUTPUT_NAME ${exename}${ARTIFACT_SUFFIX}
        )
-      target_link_libraries(${CMAKE_PROJECT_NAME}_${exename}${ARTIFACT_SUFFIX} testutillib${ARTIFACT_SUFFIX} gtest ${LIBS})
+      target_link_libraries(${CMAKE_PROJECT_NAME}_${exename}${ARTIFACT_SUFFIX} testutillib${ARTIFACT_SUFFIX} testharness gtest ${ROCKSDB_LIB})
      if(NOT "${exename}" MATCHES "db_sanity_test")
        add_test(NAME ${exename} COMMAND ${exename}${ARTIFACT_SUFFIX})
        add_dependencies(check ${CMAKE_PROJECT_NAME}_${exename}${ARTIFACT_SUFFIX})
      endif()
-  endforeach(sourcefile ${TEST_EXES})
+  endforeach(sourcefile ${TESTS})

-  # C executables must link to a shared object
-  set(C_TESTS db/c_test.c)
-  set(C_TEST_EXES ${C_TESTS})
+  if(WIN32)
+    # C executables must link to a shared object
+    if(ROCKSDB_BUILD_SHARED)
+      set(ROCKSDB_LIB_FOR_C ${ROCKSDB_SHARED_LIB})
+    else()
+      set(ROCKSDB_LIB_FOR_C OFF)
+    endif()
+  else()
+    set(ROCKSDB_LIB_FOR_C ${ROCKSDB_LIB})
+  endif()

-  foreach(sourcefile ${C_TEST_EXES})
-      string(REPLACE ".c" "" exename ${sourcefile})
-      string(REGEX REPLACE "^((.+)/)+" "" exename ${exename})
-      add_executable(${exename}${ARTIFACT_SUFFIX} ${sourcefile})
-      set_target_properties(${exename}${ARTIFACT_SUFFIX}
-        PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD_RELEASE 1
-        EXCLUDE_FROM_DEFAULT_BUILD_MINRELEASE 1
-        EXCLUDE_FROM_DEFAULT_BUILD_RELWITHDEBINFO 1
-        )
-      target_link_libraries(${exename}${ARTIFACT_SUFFIX} ${ROCKSDB_IMPORT_LIB} testutillib${ARTIFACT_SUFFIX})
-      add_test(NAME ${exename} COMMAND ${exename}${ARTIFACT_SUFFIX})
-      add_dependencies(check ${exename}${ARTIFACT_SUFFIX})
-  endforeach(sourcefile ${C_TEST_EXES})
+  if(ROCKSDB_LIB_FOR_C)
+    set(C_TESTS db/c_test.c)
+    # C executables must link to a shared object
+    add_executable(c_test db/c_test.c)
+    target_link_libraries(c_test ${ROCKSDB_SHARED_LIB} testharness)
+    add_test(NAME c_test COMMAND c_test${ARTIFACT_SUFFIX})
+    add_dependencies(check c_test)
+  endif()
+endif()
+
+option(WITH_BENCHMARK_TOOLS "build with benchmarks" ON)
+if(WITH_BENCHMARK_TOOLS)
+  add_executable(db_bench
+    tools/db_bench.cc
+    tools/db_bench_tool.cc)
+  target_link_libraries(db_bench
+    ${ROCKSDB_LIB})
+
+  add_executable(cache_bench
+    cache/cache_bench.cc)
+  target_link_libraries(cache_bench
+    ${ROCKSDB_LIB})
+
+  add_executable(memtablerep_bench
+    memtable/memtablerep_bench.cc)
+  target_link_libraries(memtablerep_bench
+    ${ROCKSDB_LIB})
+
+  add_executable(range_del_aggregator_bench
+    db/range_del_aggregator_bench.cc)
+  target_link_libraries(range_del_aggregator_bench
+    ${ROCKSDB_LIB})
+
+  add_executable(table_reader_bench
+    table/table_reader_bench.cc)
+  target_link_libraries(table_reader_bench
+    ${ROCKSDB_LIB} testharness)
+
+  add_executable(filter_bench
+    util/filter_bench.cc)
+  target_link_libraries(filter_bench
+    ${ROCKSDB_LIB})
+
+  add_executable(hash_table_bench
+    utilities/persistent_cache/hash_table_bench.cc)
+  target_link_libraries(hash_table_bench
+    ${ROCKSDB_LIB})
 endif()

 option(WITH_TOOLS "build with tools" ON)
 if(WITH_TOOLS)
  add_subdirectory(tools)
+  add_subdirectory(db_stress_tool)
+  add_custom_target(tools
+    DEPENDS ${tool_deps})
 endif()
@@ -1,3 +1,77 @@
 # Code of Conduct

-Facebook has adopted a Code of Conduct that we expect project participants to adhere to. Please [read the full text](https://code.facebook.com/codeofconduct) so that you can understand what actions will and will not be tolerated.
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to make participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies within all project spaces, and it also applies when
+an individual is representing the project or its community in public spaces.
+Examples of representing a project or community include using an official
+project e-mail address, posting via an official social media account, or acting
+as an appointed representative at an online or offline event. Representation of
+a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at <opensource-conduct@fb.com>. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+https://www.contributor-covenant.org/faq
+
@@ -1,9 +1,115 @@
 # Rocksdb Change Log
 ## Unreleased
+### Public API Change
+* Added a rocksdb::FileSystem class in include/rocksdb/file_system.h to encapsulate file creation/read/write operations, and an option DBOptions::file_system to allow a user to pass in an instance of rocksdb::FileSystem. If its a non-null value, this will take precendence over DBOptions::env for file operations. A new API rocksdb::FileSystem::Default() returns a platform default object. The DBOptions::env option and Env::Default() API will continue to be used for threading and other OS related functions, and where DBOptions::file_system is not specified, for file operations. For storage developers who are accustomed to rocksdb::Env, the interface in rocksdb::FileSystem is new and will probably undergo some changes as more storage systems are ported to it from rocksdb::Env. As of now, no env other than Posix has been ported to the new interface.
+* A new rocksdb::NewSstFileManager() API that allows the caller to pass in separate Env and FileSystem objects.
+* Changed Java API for RocksDB.keyMayExist functions to use Holder<byte[]> instead of StringBuilder, so that retrieved values need not decode to Strings.
+* A new `OptimisticTransactionDBOptions` Option that allows users to configure occ validation policy. The default policy changes from kValidateSerial to kValidateParallel to reduce mutex contention.
+
+### Bug Fixes
+* Fix a bug that can cause unnecessary bg thread to be scheduled(#6104).
+* Fix a bug in which a snapshot read could be affected by a DeleteRange after the snapshot (#6062).
+* Fix crash caused by concurrent CF iterations and drops(#6147).
+* Fixed two performance issues related to memtable history trimming. First, a new SuperVersion is now created only if some memtables were actually trimmed. Second, trimming is only scheduled if there is at least one flushed memtable that is kept in memory for the purposes of transaction conflict checking.
+* Fix a bug in WriteBatchWithIndex::MultiGetFromBatchAndDB, which is called by Transaction::MultiGet, that causes due to stale pointer access when the number of keys is > 32
+* BlobDB no longer updates the SST to blob file mapping upon failed compactions.
+* Fixed a bug where BlobDB was comparing the `ColumnFamilyHandle` pointers themselves instead of only the column family IDs when checking whether an API call uses the default column family or not.
+* Fix a race condition for cfd->log_number_ between manifest switch and memtable switch (PR 6249) when number of column families is greater than 1.
+
+### New Features
+* It is now possible to enable periodic compactions for the base DB when using BlobDB.
+* BlobDB now garbage collects non-TTL blobs when `enable_garbage_collection` is set to `true` in `BlobDBOptions`. Garbage collection is performed during compaction: any valid blobs located in the oldest N files (where N is the number of non-TTL blob files multiplied by the value of `BlobDBOptions::garbage_collection_cutoff`) encountered during compaction get relocated to new blob files, and old blob files are dropped once they are no longer needed. Note: we recommend enabling periodic compactions for the base DB when using this feature to deal with the case when some old blob files are kept alive by SSTs that otherwise do not get picked for compaction.
+* `db_bench` now supports the `garbage_collection_cutoff` option for BlobDB.
+
+## 6.6.0 (11/25/2019)
+### Bug Fixes
+* Fix data corruption caused by output of intra-L0 compaction on ingested file not being placed in correct order in L0.
+* Fix a data race between Version::GetColumnFamilyMetaData() and Compaction::MarkFilesBeingCompacted() for access to being_compacted (#6056). The current fix acquires the db mutex during Version::GetColumnFamilyMetaData(), which may cause regression.
+* Fix a bug in DBIter that is_blob_ state isn't updated when iterating backward using seek.
+* Fix a bug when format_version=3, partitioned filters, and prefix search are used in conjunction. The bug could result into Seek::(prefix) returning NotFound for an existing prefix.
+* Revert the feature "Merging iterator to avoid child iterator reseek for some cases (#5286)" since it might cause strong results when reseek happens with a different iterator upper bound.
+* Fix a bug causing a crash during ingest external file when background compaction cause severe error (file not found).
+* Fix a bug when partitioned filters and prefix search are used in conjunction, ::SeekForPrev could return invalid for an existing prefix. ::SeekForPrev might be called by the user, or internally on ::Prev, or within ::Seek if the return value involves Delete or a Merge operand.
+* Fix OnFlushCompleted fired before flush result persisted in MANIFEST when there's concurrent flush job. The bug exists since OnFlushCompleted was introduced in rocksdb 3.8.
+* Fixed an sst_dump crash on some plain table SST files.
+* Fixed a memory leak in some error cases of opening plain table SST files.
+* Fix a bug when a crash happens while calling WriteLevel0TableForRecovery for multiple column families, leading to a column family's log number greater than the first corrutped log number when the DB is being opened in PointInTime recovery mode during next recovery attempt (#5856).
+
+### New Features
+* Universal compaction to support options.periodic_compaction_seconds. A full compaction will be triggered if any file is over the threshold.
+* `GetLiveFilesMetaData` and `GetColumnFamilyMetaData` now expose the file number of SST files as well as the oldest blob file referenced by each SST.
+* A batched MultiGet API (DB::MultiGet()) that supports retrieving keys from multiple column families.
+* Full and partitioned filters in the block-based table use an improved Bloom filter implementation, enabled with format_version 5 (or above) because previous releases cannot read this filter. This replacement is faster and more accurate, especially for high bits per key or millions of keys in a single (full) filter. For example, the new Bloom filter has the same false positive rate at 9.55 bits per key as the old one at 10 bits per key, and a lower false positive rate at 16 bits per key than the old one at 100 bits per key.
+* Added AVX2 instructions to USE_SSE builds to accelerate the new Bloom filter and XXH3-based hash function on compatible x86_64 platforms (Haswell and later, ~2014).
+* Support options.ttl or options.periodic_compaction_seconds with options.max_open_files = -1. File's oldest ancester time and file creation time will be written to manifest. If it is availalbe, this information will be used instead of creation_time and file_creation_time in table properties.
+* Setting options.ttl for universal compaction now has the same meaning as setting periodic_compaction_seconds.
+* SstFileMetaData also returns file creation time and oldest ancester time.
+* The `sst_dump` command line tool `recompress` command now displays how many blocks were compressed and how many were not, in particular how many were not compressed because the compression ratio was not met (12.5% threshold for GoodCompressionRatio), as seen in the `number.block.not_compressed` counter stat since version 6.0.0.
+* The block cache usage is now takes into account the overhead of metadata per each entry. This results into more accurate management of memory. A side-effect of this feature is that less items are fit into the block cache of the same size, which would result to higher cache miss rates. This can be remedied by increasing the block cache size or passing kDontChargeCacheMetadata to its constuctor to restore the old behavior.
+* When using BlobDB, a mapping is maintained and persisted in the MANIFEST between each SST file and the oldest non-TTL blob file it references.
+* `db_bench` now supports and by default issues non-TTL Puts to BlobDB. TTL Puts can be enabled by specifying a non-zero value for the `blob_db_max_ttl_range` command line parameter explicitly.
+* `sst_dump` now supports printing BlobDB blob indexes in a human-readable format. This can be enabled by specifying the `decode_blob_index` flag on the command line.
+* A number of new information elements are now exposed through the EventListener interface. For flushes, the file numbers of the new SST file and the oldest blob file referenced by the SST are propagated. For compactions, the level, file number, and the oldest blob file referenced are passed to the client for each compaction input and output file.
+
+### Public API Change
+* RocksDB release 4.1 or older will not be able to open DB generated by the new release. 4.2 was released on Feb 23, 2016.
+* TTL Compactions in Level compaction style now initiate successive cascading compactions on a key range so that it reaches the bottom level quickly on TTL expiry. `creation_time` table property for compaction output files is now set to the minimum of the creation times of all compaction inputs.
+* With FIFO compaction style, options.periodic_compaction_seconds will have the same meaning as options.ttl. Whichever stricter will be used. With the default options.periodic_compaction_seconds value with options.ttl's default of 0, RocksDB will give a default of 30 days.
+* Added an API GetCreationTimeOfOldestFile(uint64_t* creation_time) to get the file_creation_time of the oldest SST file in the DB.
+* FilterPolicy now exposes additional API to make it possible to choose filter configurations based on context, such as table level and compaction style. See `LevelAndStyleCustomFilterPolicy` in db_bloom_filter_test.cc. While most existing custom implementations of FilterPolicy should continue to work as before, those wrapping the return of NewBloomFilterPolicy will require overriding new function `GetBuilderWithContext()`, because calling `GetFilterBitsBuilder()` on the FilterPolicy returned by NewBloomFilterPolicy is no longer supported.
+* An unlikely usage of FilterPolicy is no longer supported. Calling GetFilterBitsBuilder() on the FilterPolicy returned by NewBloomFilterPolicy will now cause an assertion violation in debug builds, because RocksDB has internally migrated to a more elaborate interface that is expected to evolve further. Custom implementations of FilterPolicy should work as before, except those wrapping the return of NewBloomFilterPolicy, which will require a new override of a protected function in FilterPolicy.
+* NewBloomFilterPolicy now takes bits_per_key as a double instead of an int. This permits finer control over the memory vs. accuracy trade-off in the new Bloom filter implementation and should not change source code compatibility.
+* The option BackupableDBOptions::max_valid_backups_to_open is now only used when opening BackupEngineReadOnly. When opening a read/write BackupEngine, anything but the default value logs a warning and is treated as the default. This change ensures that backup deletion has proper accounting of shared files to ensure they are deleted when no longer referenced by a backup.
+* Deprecate `snap_refresh_nanos` option.
+* Added DisableManualCompaction/EnableManualCompaction to stop and resume manual compaction.
+* Add TryCatchUpWithPrimary() to StackableDB in non-LITE mode.
+* Add a new Env::LoadEnv() overloaded function to return a shared_ptr to Env.
+* Flush sets file name to "(nil)" for OnTableFileCreationCompleted() if the flush does not produce any L0. This can happen if the file is empty thus delete by RocksDB.
+
+### Default Option Changes
+* Changed the default value of periodic_compaction_seconds to `UINT64_MAX - 1` which allows RocksDB to auto-tune periodic compaction scheduling. When using the default value, periodic compactions are now auto-enabled if a compaction filter is used. A value of `0` will turn off the feature completely.
+* Changed the default value of ttl to `UINT64_MAX - 1` which allows RocksDB to auto-tune ttl value. When using the default value, TTL will be auto-enabled to 30 days, when the feature is supported. To revert the old behavior, you can explicitly set it to 0.
+
+### Performance Improvements
+* For 64-bit hashing, RocksDB is standardizing on a slightly modified preview version of XXH3. This function is now used for many non-persisted hashes, along with fastrange64() in place of the modulus operator, and some benchmarks show a slight improvement.
+* Level iterator to invlidate the iterator more often in prefix seek and the level is filtered out by prefix bloom.
+
+## 6.5.2 (11/15/2019)
+### Bug Fixes
+* Fix a assertion failure in MultiGet() when BlockBasedTableOptions::no_block_cache is true and there is no compressed block cache
+* Fix a buffer overrun problem in BlockBasedTable::MultiGet() when compression is enabled and no compressed block cache is configured.
+* If a call to BackupEngine::PurgeOldBackups or BackupEngine::DeleteBackup suffered a crash, power failure, or I/O error, files could be left over from old backups that could only be purged with a call to GarbageCollect. Any call to PurgeOldBackups, DeleteBackup, or GarbageCollect should now suffice to purge such files.
+
+## 6.5.1 (10/16/2019)
+### Bug Fixes
+* Revert the feature "Merging iterator to avoid child iterator reseek for some cases (#5286)" since it might cause strange results when reseek happens with a different iterator upper bound.
+* Fix a bug in BlockBasedTableIterator that might return incorrect results when reseek happens with a different iterator upper bound.
+* Fix a bug when partitioned filters and prefix search are used in conjunction, ::SeekForPrev could return invalid for an existing prefix. ::SeekForPrev might be called by the user, or internally on ::Prev, or within ::Seek if the return value involves Delete or a Merge operand.
+
+## 6.5.0 (9/13/2019)
+### Bug Fixes
+* Fixed a number of data races in BlobDB.
+* Fix a bug where the compaction snapshot refresh feature is not disabled as advertised when `snap_refresh_nanos` is set to 0..
+* Fix bloom filter lookups by the MultiGet batching API when BlockBasedTableOptions::whole_key_filtering is false, by checking that a key is in the perfix_extractor domain and extracting the prefix before looking up.
+* Fix a bug in file ingestion caused by incorrect file number allocation when the number of column families involved in the ingestion exceeds 2.
+
+### New Features
+* Introduced DBOptions::max_write_batch_group_size_bytes to configure maximum limit on number of bytes that are written in a single batch of WAL or memtable write. It is followed when the leader write size is larger than 1/8 of this limit.
+* VerifyChecksum() by default will issue readahead. Allow ReadOptions to be passed in to those functions to override the readhead size. For checksum verifying before external SST file ingestion, a new option IngestExternalFileOptions.verify_checksums_readahead_size, is added for this readahead setting.
+* When user uses options.force_consistency_check in RocksDb, instead of crashing the process, we now pass the error back to the users without killing the process.
+* Add an option `memtable_insert_hint_per_batch` to WriteOptions. If it is true, each WriteBatch will maintain its own insert hints for each memtable in concurrent write. See include/rocksdb/options.h for more details.
+
+### Public API Change
+* Added max_write_buffer_size_to_maintain option to better control memory usage of immutable memtables.
+* Added a lightweight API GetCurrentWalFile() to get last live WAL filename and size. Meant to be used as a helper for backup/restore tooling in a larger ecosystem such as MySQL with a MyRocks storage engine.
+* The MemTable Bloom filter, when enabled, now always uses cache locality. Options::bloom_locality now only affects the PlainTable SST format.
+
+### Performance Improvements
+* Improve the speed of the MemTable Bloom filter, reducing the write overhead of enabling it by 1/3 to 1/2, with similar benefit to read performance.

 ## 6.4.0 (7/30/2019)
 ### Default Option Change
-* LRUCacheOptions.high_pri_pool_ratio is set to 0.5 (previously 0.0) by default, which means that by default midpoint insertion is enabled. The same change is made for the default value of high_pri_pool_ratio argument in NewLRUCache(). When block cache is not explictly created, the small block cache created by BlockBasedTable will still has this option to be 0.0.
+* LRUCacheOptions.high_pri_pool_ratio is set to 0.5 (previously 0.0) by default, which means that by default midpoint insertion is enabled. The same change is made for the default value of high_pri_pool_ratio argument in NewLRUCache(). When block cache is not explicitly created, the small block cache created by BlockBasedTable will still has this option to be 0.0.
 * Change BlockBasedTableOptions.cache_index_and_filter_blocks_with_high_priority's default value from false to true.

 ### Public API Change
@@ -17,21 +123,33 @@
 * ldb sometimes uses a string-append merge operator if no merge operator is passed in. This is to allow users to print keys from a DB with a merge operator.
 * Replaces old Registra with ObjectRegistry to allow user to create custom object from string, also add LoadEnv() to Env.
 * Added new overload of GetApproximateSizes which gets SizeApproximationOptions object and returns a Status. The older overloads are redirecting their calls to this new method and no longer assert if the include_flags doesn't have either of INCLUDE_MEMTABLES or INCLUDE_FILES bits set. It's recommended to use the new method only, as it is more type safe and returns a meaningful status in case of errors.
+* LDBCommandRunner::RunCommand() to return the status code as an integer, rather than call exit() using the code.

 ### New Features
 * Add argument `--secondary_path` to ldb to open the database as the secondary instance. This would keep the original DB intact.
 * Compression dictionary blocks are now prefetched and pinned in the cache (based on the customer's settings) the same way as index and filter blocks.
 * Added DBOptions::log_readahead_size which specifies the number of bytes to prefetch when reading the log. This is mostly useful for reading a remotely located log, as it can save the number of round-trips. If 0 (default), then the prefetching is disabled.
+* Added new option in SizeApproximationOptions used with DB::GetApproximateSizes. When approximating the files total size that is used to store a keys range, allow approximation with an error margin of up to total_files_size * files_size_error_margin. This allows to take some shortcuts in files size approximation, resulting in better performance, while guaranteeing the resulting error is within a reasonable margin.
+* Support loading custom objects in unit tests. In the affected unit tests, RocksDB will create custom Env objects based on environment variable TEST_ENV_URI. Users need to make sure custom object types are properly registered. For example, a static library should expose a `RegisterCustomObjects` function. By linking the unit test binary with the static library, the unit test can execute this function.

 ### Performance Improvements
-* Reduce iterator key comparision for upper/lower bound check.
+* Reduce iterator key comparison for upper/lower bound check.
 * Improve performance of row_cache: make reads with newer snapshots than data in an SST file share the same cache key, except in some transaction cases.
 * The compression dictionary is no longer copied to a new object upon retrieval.

 ### Bug Fixes
 * Fix ingested file and directory not being fsync.
 * Return TryAgain status in place of Corruption when new tail is not visible to TransactionLogIterator.
+* Fixed a regression where the fill_cache read option also affected index blocks.
+* Fixed an issue where using cache_index_and_filter_blocks==false affected partitions of partitioned indexes/filters as well.

+## 6.3.2 (8/15/2019)
+### Public API Change
+* The semantics of the per-block-type block read counts in the performance context now match those of the generic block_read_count.
+
+### Bug Fixes
+* Fixed a regression where the fill_cache read option also affected index blocks.
+* Fixed an issue where using cache_index_and_filter_blocks==false affected partitions of partitioned indexes as well.

 ## 6.3.1 (7/24/2019)
 ### Bug Fixes
@@ -54,6 +172,7 @@
 * Add an option `unordered_write` which trades snapshot guarantees with higher write throughput. When used with WRITE_PREPARED transactions with two_write_queues=true, it offers higher throughput with however no compromise on guarantees.
 * Allow DBImplSecondary to remove memtables with obsolete data after replaying MANIFEST and WAL.
 * Add an option `failed_move_fall_back_to_copy` (default is true) for external SST ingestion. When `move_files` is true and hard link fails, ingestion falls back to copy if `failed_move_fall_back_to_copy` is true. Otherwise, ingestion reports an error.
+* Add command `list_file_range_deletes` in ldb, which prints out tombstones in SST files.

 ### Performance Improvements
 * Reduce binary search when iterator reseek into the same data block.
@@ -73,7 +192,6 @@
 * Fix a bug caused by secondary not skipping the beginning of new MANIFEST.
 * On DB open, delete WAL trash files left behind in wal_dir

-
 ## 6.2.0 (4/30/2019)
 ### New Features
 * Add an option `strict_bytes_per_sync` that causes a file-writing thread to block rather than exceed the limit on bytes pending writeback specified by `bytes_per_sync` or `wal_bytes_per_sync`.
@@ -111,7 +229,7 @@
 * Introduce two more stats levels, kExceptHistogramOrTimers and kExceptTimers.
 * Added a feature to perform data-block sampling for compressibility, and report stats to user.
 * Add support for trace filtering.
-* Add DBOptions.avoid_unnecessary_blocking_io. If true, we avoid file deletion when destorying ColumnFamilyHandle and Iterator. Instead, a job is scheduled to delete the files in background.
+* Add DBOptions.avoid_unnecessary_blocking_io. If true, we avoid file deletion when destroying ColumnFamilyHandle and Iterator. Instead, a job is scheduled to delete the files in background.

 ### Public API Change
 * Remove bundled fbson library.
@@ -490,7 +608,7 @@ if set to something > 0 user will see 2 changes in iterators behavior 1) only ke

 ## 5.2.0 (02/08/2017)
 ### Public API Change
-* NewLRUCache() will determine number of shard bits automatically based on capacity, if the user doesn't pass one. This also impacts the default block cache when the user doesn't explict provide one.
+* NewLRUCache() will determine number of shard bits automatically based on capacity, if the user doesn't pass one. This also impacts the default block cache when the user doesn't explicit provide one.
 * Change the default of delayed slowdown value to 16MB/s and further increase the L0 stop condition to 36 files.
 * Options::use_direct_writes and Options::use_direct_reads are now ready to use.
 * (Experimental) Two-level indexing that partition the index and creates a 2nd level index on the partitions. The feature can be enabled by setting kTwoLevelIndexSearch as IndexType and configuring index_per_partition.
@@ -561,7 +679,7 @@ if set to something > 0 user will see 2 changes in iterators behavior 1) only ke

 ### New Features
 * A tool to migrate DB after options change. See include/rocksdb/utilities/option_change_migration.h.
-* Add ReadOptions.background_purge_on_iterator_cleanup. If true, we avoid file deletion when destorying iterators.
+* Add ReadOptions.background_purge_on_iterator_cleanup. If true, we avoid file deletion when destroying iterators.

 ## 4.10.0 (7/5/2016)
 ### Public API Change
@@ -89,7 +89,7 @@ endif

 ifeq ($(MAKECMDGOALS),rocksdbjavastaticreleasedocker)
 	ifneq ($(DEBUG_LEVEL),2)
-        	DEBUG_LEVEL=0
+		DEBUG_LEVEL=0
 	endif
 endif

@@ -143,7 +143,7 @@ CFLAGS +=  -DHAVE_POWER8
 HAVE_POWER8=1
 endif

-ifeq (,$(shell $(CXX) -fsyntax-only -march=armv8-a+crc -xc /dev/null 2>&1))
+ifeq (,$(shell $(CXX) -fsyntax-only -march=armv8-a+crc+crypto -xc /dev/null 2>&1))
 CXXFLAGS += -march=armv8-a+crc+crypto
 CFLAGS += -march=armv8-a+crc+crypto
 ARMCRC_SOURCE=1
@@ -256,8 +256,8 @@ endif
 ifdef COMPILE_WITH_TSAN
 	DISABLE_JEMALLOC=1
 	EXEC_LDFLAGS += -fsanitize=thread
-	PLATFORM_CCFLAGS += -fsanitize=thread -fPIC
-	PLATFORM_CXXFLAGS += -fsanitize=thread -fPIC
+	PLATFORM_CCFLAGS += -fsanitize=thread -fPIC -DFOLLY_SANITIZE_THREAD
+	PLATFORM_CXXFLAGS += -fsanitize=thread -fPIC -DFOLLY_SANITIZE_THREAD
        # Turn off -pg when enabling TSAN testing, because that induces
        # a link failure.  TODO: find the root cause
 	PROFILING_FLAGS =
@@ -304,9 +304,13 @@ ifndef DISABLE_JEMALLOC
 	PLATFORM_CCFLAGS += $(JEMALLOC_INCLUDE)
 endif

+ifndef USE_FOLLY_DISTRIBUTED_MUTEX
+	USE_FOLLY_DISTRIBUTED_MUTEX=0
+endif
+
 export GTEST_THROW_ON_FAILURE=1
 export GTEST_HAS_EXCEPTIONS=1
-GTEST_DIR = ./third-party/gtest-1.7.0/fused-src
+GTEST_DIR = ./third-party/gtest-1.8.1/fused-src
 # AIX: pre-defined system headers are surrounded by an extern "C" block
 ifeq ($(PLATFORM), OS_AIX)
 	PLATFORM_CCFLAGS += -I$(GTEST_DIR)
@@ -316,6 +320,23 @@ else
 	PLATFORM_CXXFLAGS += -isystem $(GTEST_DIR)
 endif

+ifeq ($(USE_FOLLY_DISTRIBUTED_MUTEX),1)
+	FOLLY_DIR = ./third-party/folly
+	# AIX: pre-defined system headers are surrounded by an extern "C" block
+	ifeq ($(PLATFORM), OS_AIX)
+		PLATFORM_CCFLAGS += -I$(FOLLY_DIR)
+		PLATFORM_CXXFLAGS += -I$(FOLLY_DIR)
+	else
+		PLATFORM_CCFLAGS += -isystem $(FOLLY_DIR)
+		PLATFORM_CXXFLAGS += -isystem $(FOLLY_DIR)
+	endif
+endif
+
+ifdef TEST_CACHE_LINE_SIZE
+  PLATFORM_CCFLAGS += -DTEST_CACHE_LINE_SIZE=$(TEST_CACHE_LINE_SIZE)
+  PLATFORM_CXXFLAGS += -DTEST_CACHE_LINE_SIZE=$(TEST_CACHE_LINE_SIZE)
+endif
+
 # This (the first rule) must depend on "all".
 default: all

@@ -402,6 +423,9 @@ endif

 LIBOBJECTS += $(TOOL_LIB_SOURCES:.cc=.o)
 MOCKOBJECTS = $(MOCK_LIB_SOURCES:.cc=.o)
+ifeq ($(USE_FOLLY_DISTRIBUTED_MUTEX),1)
+  FOLLYOBJECTS = $(FOLLY_SOURCES:.cpp=.o)
+endif

 GTEST = $(GTEST_DIR)/gtest/gtest-all.o
 TESTUTIL = ./test_util/testutil.o
@@ -415,6 +439,8 @@ BENCHTOOLOBJECTS = $(BENCH_LIB_SOURCES:.cc=.o) $(LIBOBJECTS) $(TESTUTIL)

 ANALYZETOOLOBJECTS = $(ANALYZER_LIB_SOURCES:.cc=.o)

+STRESSTOOLOBJECTS = $(STRESS_LIB_SOURCES:.cc=.o) $(LIBOBJECTS) $(TESTUTIL)
+
 EXPOBJECTS = $(LIBOBJECTS) $(TESTUTIL)

 TESTS = \
@@ -434,6 +460,7 @@ TESTS = \
 	env_test \
 	env_logger_test \
 	hash_test \
+	random_test \
 	thread_local_test \
 	rate_limiter_test \
 	perf_context_test \
@@ -445,6 +472,7 @@ TESTS = \
 	db_iter_test \
 	db_iter_stress_test \
 	db_log_iter_test \
+	db_bloom_filter_test \
 	db_compaction_filter_test \
 	db_compaction_test \
 	db_dynamic_level_test \
@@ -453,6 +481,7 @@ TESTS = \
 	db_iterator_test \
 	db_memtable_test \
 	db_merge_operator_test \
+	db_merge_operand_test \
 	db_options_test \
 	db_range_del_test \
 	db_secondary_test \
@@ -479,6 +508,7 @@ TESTS = \
 	fault_injection_test \
 	filelock_test \
 	filename_test \
+	file_reader_writer_test \
 	block_based_filter_block_test \
 	full_filter_block_test \
 	partitioned_filter_block_test \
@@ -566,6 +596,10 @@ TESTS = \
 	block_cache_tracer_test \
 	block_cache_trace_analyzer_test \

+ifeq ($(USE_FOLLY_DISTRIBUTED_MUTEX),1)
+	TESTS += folly_synchronization_distributed_mutex_test
+endif
+
 PARALLEL_TEST = \
 	backupable_db_test \
 	db_bloom_filter_test \
@@ -618,7 +652,7 @@ TEST_LIBS = \
 	librocksdb_env_basic_test.a

 # TODO: add back forward_iterator_bench, after making it build in all environemnts.
-BENCHMARKS = db_bench table_reader_bench cache_bench memtablerep_bench persistent_cache_bench range_del_aggregator_bench
+BENCHMARKS = db_bench table_reader_bench cache_bench memtablerep_bench filter_bench persistent_cache_bench range_del_aggregator_bench

 # if user didn't config LIBNAME, set the default
 ifeq ($(LIBNAME),)
@@ -631,6 +665,7 @@ endif
 endif
 LIBRARY = ${LIBNAME}.a
 TOOLS_LIBRARY = ${LIBNAME}_tools.a
+STRESS_LIBRARY = ${LIBNAME}_stress.a

 ROCKSDB_MAJOR = $(shell egrep "ROCKSDB_MAJOR.[0-9]" include/rocksdb/version.h | cut -d ' ' -f 3)
 ROCKSDB_MINOR = $(shell egrep "ROCKSDB_MINOR.[0-9]" include/rocksdb/version.h | cut -d ' ' -f 3)
@@ -709,7 +744,8 @@ endif  # PLATFORM_SHARED_EXT
 	release tags tags0 valgrind_check whitebox_crash_test format static_lib shared_lib all \
 	dbg rocksdbjavastatic rocksdbjava install install-static install-shared uninstall \
 	analyze tools tools_lib \
-	blackbox_crash_test_with_atomic_flush whitebox_crash_test_with_atomic_flush
+	blackbox_crash_test_with_atomic_flush whitebox_crash_test_with_atomic_flush  \
+	blackbox_crash_test_with_txn whitebox_crash_test_with_txn


 all: $(LIBRARY) $(BENCHMARKS) tools tools_lib test_libs $(TESTS)
@@ -720,6 +756,8 @@ static_lib: $(LIBRARY)

 shared_lib: $(SHARED)

+stress_lib: $(STRESS_LIBRARY)
+
 tools: $(TOOLS)

 tools_lib: $(TOOLS_LIBRARY)
@@ -901,6 +939,7 @@ check: all
 	fi
 	rm -rf $(TMPD)
 ifneq ($(PLATFORM), OS_AIX)
+	python tools/check_all_python.py
 ifeq ($(filter -DROCKSDB_LITE,$(OPT)),)
 	python tools/ldb_test.py
 	sh tools/rocksdb_dump_test.sh
@@ -919,12 +958,17 @@ crash_test: whitebox_crash_test blackbox_crash_test

 crash_test_with_atomic_flush: whitebox_crash_test_with_atomic_flush blackbox_crash_test_with_atomic_flush

+crash_test_with_txn: whitebox_crash_test_with_txn blackbox_crash_test_with_txn
+
 blackbox_crash_test: db_stress
 	python -u tools/db_crashtest.py --simple blackbox $(CRASH_TEST_EXT_ARGS)
 	python -u tools/db_crashtest.py blackbox $(CRASH_TEST_EXT_ARGS)

 blackbox_crash_test_with_atomic_flush: db_stress
-	python -u tools/db_crashtest.py --enable_atomic_flush blackbox $(CRASH_TEST_EXT_ARGS)
+	python -u tools/db_crashtest.py --cf_consistency blackbox $(CRASH_TEST_EXT_ARGS)
+
+blackbox_crash_test_with_txn: db_stress
+	python -u tools/db_crashtest.py --txn blackbox $(CRASH_TEST_EXT_ARGS)

 ifeq ($(CRASH_TEST_KILL_ODD),)
  CRASH_TEST_KILL_ODD=888887
@@ -937,7 +981,11 @@ whitebox_crash_test: db_stress
      $(CRASH_TEST_KILL_ODD) $(CRASH_TEST_EXT_ARGS)

 whitebox_crash_test_with_atomic_flush: db_stress
-	python -u tools/db_crashtest.py --enable_atomic_flush whitebox  --random_kill_odd \
+	python -u tools/db_crashtest.py --cf_consistency whitebox  --random_kill_odd \
+      $(CRASH_TEST_KILL_ODD) $(CRASH_TEST_EXT_ARGS)
+
+whitebox_crash_test_with_txn: db_stress
+	python -u tools/db_crashtest.py --txn whitebox --random_kill_odd \
      $(CRASH_TEST_KILL_ODD) $(CRASH_TEST_EXT_ARGS)

 asan_check:
@@ -955,6 +1003,11 @@ asan_crash_test_with_atomic_flush:
 	COMPILE_WITH_ASAN=1 $(MAKE) crash_test_with_atomic_flush
 	$(MAKE) clean

+asan_crash_test_with_txn:
+	$(MAKE) clean
+	COMPILE_WITH_ASAN=1 $(MAKE) crash_test_with_txn
+	$(MAKE) clean
+
 ubsan_check:
 	$(MAKE) clean
 	COMPILE_WITH_UBSAN=1 $(MAKE) check -j32
@@ -970,6 +1023,11 @@ ubsan_crash_test_with_atomic_flush:
 	COMPILE_WITH_UBSAN=1 $(MAKE) crash_test_with_atomic_flush
 	$(MAKE) clean

+ubsan_crash_test_with_txn:
+	$(MAKE) clean
+	COMPILE_WITH_UBSAN=1 $(MAKE) crash_test_with_txn
+	$(MAKE) clean
+
 valgrind_test:
 	ROCKSDB_VALGRIND_RUN=1 DISABLE_JEMALLOC=1 $(MAKE) valgrind_check

@@ -1039,6 +1097,9 @@ parallel_check: $(TESTS)
 		TMPD=$(TMPD) J=$(J) db_test=0 parloop;

 analyze: clean
+	USE_CLANG=1 $(MAKE) analyze_incremental
+
+analyze_incremental:
 	$(CLANG_SCAN_BUILD) --use-analyzer=$(CLANG_ANALYZER) \
 		--use-c++=$(CXX) --use-cc=$(CC) --status-bugs \
 		-o $(CURDIR)/scan_build_report \
@@ -1067,14 +1128,23 @@ unity_test: db/db_test.o db/db_test_util.o $(TESTHARNESS) $(TOOLLIBOBJECTS) unit
 rocksdb.h rocksdb.cc: build_tools/amalgamate.py Makefile $(LIB_SOURCES) unity.cc
 	build_tools/amalgamate.py -I. -i./include unity.cc -x include/rocksdb/c.h -H rocksdb.h -o rocksdb.cc

-clean:
+clean: clean-ext-libraries-all clean-rocks
+
+clean-not-downloaded: clean-ext-libraries-bin clean-rocks
+
+clean-rocks:
 	rm -f $(BENCHMARKS) $(TOOLS) $(TESTS) $(PARALLEL_TEST) $(LIBRARY) $(SHARED)
 	rm -rf $(CLEAN_FILES) ios-x86 ios-arm scan_build_report
 	$(FIND) . -name "*.[oda]" -exec rm -f {} \;
 	$(FIND) . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" -exec rm {} \;
-	rm -rf bzip2* snappy* zlib* lz4* zstd*
 	cd java; $(MAKE) clean

+clean-ext-libraries-all:
+	rm -rf bzip2* snappy* zlib* lz4* zstd*
+
+clean-ext-libraries-bin:
+	find . -maxdepth 1 -type d \( -name bzip2\* -or -name snappy\* -or -name zlib\* -or -name lz4\* -or -name zstd\* \) -prune -exec rm -rf {} \;
+
 tags:
 	ctags -R .
 	cscope -b `$(FIND) . -name '*.cc'` `$(FIND) . -name '*.h'` `$(FIND) . -name '*.c'`
@@ -1104,6 +1174,10 @@ $(TOOLS_LIBRARY): $(BENCH_LIB_SOURCES:.cc=.o) $(TOOL_LIB_SOURCES:.cc=.o) $(LIB_S
 	$(AM_V_AR)rm -f $@
 	$(AM_V_at)$(AR) $(ARFLAGS) $@ $^

+$(STRESS_LIBRARY): $(LIB_SOURCES:.cc=.o) $(TESTUTIL) $(ANALYZER_LIB_SOURCES:.cc=.o) $(STRESS_LIB_SOURCES:.cc=.o)
+	$(AM_V_AR)rm -f $@
+	$(AM_V_at)$(AR) $(ARFLAGS) $@ $^
+
 librocksdb_env_basic_test.a: env/env_basic_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_V_AR)rm -f $@
 	$(AM_V_at)$(AR) $(ARFLAGS) $@ $^
@@ -1117,6 +1191,11 @@ trace_analyzer: tools/trace_analyzer.o $(ANALYZETOOLOBJECTS) $(LIBOBJECTS)
 block_cache_trace_analyzer: tools/block_cache_analyzer/block_cache_trace_analyzer_tool.o $(ANALYZETOOLOBJECTS) $(LIBOBJECTS)
 	$(AM_LINK)

+ifeq ($(USE_FOLLY_DISTRIBUTED_MUTEX),1)
+folly_synchronization_distributed_mutex_test: $(LIBOBJECTS) $(TESTHARNESS) $(FOLLYOBJECTS) third-party/folly/folly/synchronization/test/DistributedMutexTest.o
+	$(AM_LINK)
+endif
+
 cache_bench: cache/cache_bench.o $(LIBOBJECTS) $(TESTUTIL)
 	$(AM_LINK)

@@ -1126,7 +1205,10 @@ persistent_cache_bench: utilities/persistent_cache/persistent_cache_bench.o $(LI
 memtablerep_bench: memtable/memtablerep_bench.o $(LIBOBJECTS) $(TESTUTIL)
 	$(AM_LINK)

-db_stress: tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL)
+filter_bench: util/filter_bench.o $(LIBOBJECTS) $(TESTUTIL)
+	$(AM_LINK)
+
+db_stress: db_stress_tool/db_stress.o $(STRESSTOOLOBJECTS)
 	$(AM_LINK)

 write_stress: tools/write_stress.o $(LIBOBJECTS) $(TESTUTIL)
@@ -1168,6 +1250,9 @@ coding_test: util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS)
 hash_test: util/hash_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

+random_test: util/random_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(AM_LINK)
+
 option_change_migration_test: utilities/option_change_migration/option_change_migration_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

@@ -1195,7 +1280,7 @@ histogram_test: monitoring/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS)
 thread_local_test: util/thread_local_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

-corruption_test: db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS)
+corruption_test: db/corruption_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

 crc32c_test: util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS)
@@ -1252,6 +1337,9 @@ db_memtable_test: db/db_memtable_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHA
 db_merge_operator_test: db/db_merge_operator_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

+db_merge_operand_test: db/db_merge_operand_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(AM_LINK)
+
 db_options_test: db/db_options_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

@@ -1470,10 +1558,10 @@ util_merge_operators_test: utilities/util_merge_operators_test.o $(LIBOBJECTS) $
 options_file_test: db/options_file_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

-deletefile_test: db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS)
+deletefile_test: db/deletefile_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

-obsolete_files_test: db/obsolete_files_test.o $(LIBOBJECTS) $(TESTHARNESS)
+obsolete_files_test: db/obsolete_files_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(AM_LINK)

 rocksdb_dump: tools/dump/rocksdb_dump.o $(LIBOBJECTS)
@@ -1662,7 +1750,7 @@ JAVA_INCLUDE = -I$(JAVA_HOME)/include/ -I$(JAVA_HOME)/include/linux
 ifeq ($(PLATFORM), OS_SOLARIS)
 	ARCH := $(shell isainfo -b)
 else ifeq ($(PLATFORM), OS_OPENBSD)
-	ifneq (,$(filter $(MACHINE), amd64 arm64 sparc64 aarch64))
+	ifneq (,$(filter amd64 ppc64 ppc64le arm64 aarch64 sparc64, $(MACHINE)))
 		ARCH := 64
 	else
 		ARCH := 32
@@ -1671,15 +1759,23 @@ else
 	ARCH := $(shell getconf LONG_BIT)
 endif

-ifeq (,$(findstring ppc,$(MACHINE)))
-        ROCKSDBJNILIB = librocksdbjni-linux$(ARCH).so
+ifeq ($(shell ldd /usr/bin/env 2>/dev/null | grep -q musl; echo $$?),0)
+        JNI_LIBC = musl
+# GNU LibC (or glibc) is so pervasive we can assume it is the default
+# else
+#        JNI_LIBC = glibc
+endif
+
+ifneq ($(origin JNI_LIBC), undefined)
+  JNI_LIBC_POSTFIX = -$(JNI_LIBC)
+endif
+
+ifneq (,$(filter ppc% arm64 aarch64 sparc64, $(MACHINE)))
+	ROCKSDBJNILIB = librocksdbjni-linux-$(MACHINE)$(JNI_LIBC_POSTFIX).so
 else
-        ROCKSDBJNILIB = librocksdbjni-linux-$(MACHINE).so
+	ROCKSDBJNILIB = librocksdbjni-linux$(ARCH)$(JNI_LIBC_POSTFIX).so
 endif
-ifneq (,$(findstring aarch64,$(MACHINE)))
-        ROCKSDBJNILIB = librocksdbjni-linux-$(MACHINE).so
-endif
-ROCKSDB_JAR = rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-linux$(ARCH).jar
+ROCKSDB_JAR = rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-linux$(ARCH)$(JNI_LIBC_POSTFIX).jar
 ROCKSDB_JAR_ALL = rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH).jar
 ROCKSDB_JAVADOCS_JAR = rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-javadoc.jar
 ROCKSDB_SOURCES_JAR = rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-sources.jar
@@ -1690,15 +1786,15 @@ ZLIB_SHA256 ?= c3e5e9fdd5004dcb542feda5ee4f0ff0744628baf8ed2dd5d66f8ca1197cb1a1
 ZLIB_DOWNLOAD_BASE ?= http://zlib.net
 BZIP2_VER ?= 1.0.6
 BZIP2_SHA256 ?= a2848f34fcd5d6cf47def00461fcb528a0484d8edef8208d6d2e2909dc61d9cd
-BZIP2_DOWNLOAD_BASE ?= https://web.archive.org/web/20180624184835/http://www.bzip.org
+BZIP2_DOWNLOAD_BASE ?= https://downloads.sourceforge.net/project/bzip2
 SNAPPY_VER ?= 1.1.7
 SNAPPY_SHA256 ?= 3dfa02e873ff51a11ee02b9ca391807f0c8ea0529a4924afa645fbf97163f9d4
 SNAPPY_DOWNLOAD_BASE ?= https://github.com/google/snappy/archive
-LZ4_VER ?= 1.8.3
-LZ4_SHA256 ?= 33af5936ac06536805f9745e0b6d61da606a1f8b4cc5c04dd3cbaca3b9b4fc43
+LZ4_VER ?= 1.9.2
+LZ4_SHA256 ?= 658ba6191fa44c92280d4aa2c271b0f4fbc0e34d249578dd05e50e76d0e5efcc
 LZ4_DOWNLOAD_BASE ?= https://github.com/lz4/lz4/archive
-ZSTD_VER ?= 1.4.0
-ZSTD_SHA256 ?= 63be339137d2b683c6d19a9e34f4fb684790e864fee13c7dd40e197a64c705c1
+ZSTD_VER ?= 1.4.4
+ZSTD_SHA256 ?= a364f5162c7d1a455cc915e8e3cf5f4bd8b75d09bc0f53965b0c9ca1383c52c8
 ZSTD_DOWNLOAD_BASE ?= https://github.com/facebook/zstd/archive
 CURL_SSL_OPTS ?= --tlsv1

@@ -1752,7 +1848,7 @@ endif
 libbz2.a:
 	-rm -rf bzip2-$(BZIP2_VER)
 ifeq (,$(wildcard ./bzip2-$(BZIP2_VER).tar.gz))
-	curl --output bzip2-$(BZIP2_VER).tar.gz -L ${BZIP2_DOWNLOAD_BASE}/$(BZIP2_VER)/bzip2-$(BZIP2_VER).tar.gz
+	curl --output bzip2-$(BZIP2_VER).tar.gz -L ${CURL_SSL_OPTS} ${BZIP2_DOWNLOAD_BASE}/bzip2-$(BZIP2_VER).tar.gz
 endif
 	BZIP2_SHA256_ACTUAL=`$(SHA256_CMD) bzip2-$(BZIP2_VER).tar.gz | cut -d ' ' -f 1`; \
 	if [ "$(BZIP2_SHA256)" != "$$BZIP2_SHA256_ACTUAL" ]; then \
@@ -1853,27 +1949,47 @@ rocksdbjavastatic: $(java_static_all_libobjects)
 	cd java/src/main/java;jar -cf ../../../target/$(ROCKSDB_SOURCES_JAR) org

 rocksdbjavastaticrelease: rocksdbjavastatic
-	cd java/crossbuild && vagrant destroy -f && vagrant up linux32 && vagrant halt linux32 && vagrant up linux64 && vagrant halt linux64
+	cd java/crossbuild && (vagrant destroy -f || true) && vagrant up linux32 && vagrant halt linux32 && vagrant up linux64 && vagrant halt linux64 && vagrant up linux64-musl && vagrant halt linux64-musl
 	cd java;jar -cf target/$(ROCKSDB_JAR_ALL) HISTORY*.md
 	cd java/target;jar -uf $(ROCKSDB_JAR_ALL) librocksdbjni-*.so librocksdbjni-*.jnilib
 	cd java/target/classes;jar -uf ../$(ROCKSDB_JAR_ALL) org/rocksdb/*.class org/rocksdb/util/*.class

-rocksdbjavastaticreleasedocker: rocksdbjavastatic rocksdbjavastaticdockerx86 rocksdbjavastaticdockerx86_64
+rocksdbjavastaticreleasedocker: rocksdbjavastatic rocksdbjavastaticdockerx86 rocksdbjavastaticdockerx86_64 rocksdbjavastaticdockerx86musl rocksdbjavastaticdockerx86_64musl
 	cd java;jar -cf target/$(ROCKSDB_JAR_ALL) HISTORY*.md
 	cd java/target;jar -uf $(ROCKSDB_JAR_ALL) librocksdbjni-*.so librocksdbjni-*.jnilib
 	cd java/target/classes;jar -uf ../$(ROCKSDB_JAR_ALL) org/rocksdb/*.class org/rocksdb/util/*.class

 rocksdbjavastaticdockerx86:
 	mkdir -p java/target
-	docker run --rm --name rocksdb_linux_x86-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos6_x86-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+	docker run --rm --name rocksdb_linux_x86-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos6_x86-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh

 rocksdbjavastaticdockerx86_64:
 	mkdir -p java/target
-	docker run --rm --name rocksdb_linux_x64-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos6_x64-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+	docker run --rm --name rocksdb_linux_x64-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos6_x64-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh

 rocksdbjavastaticdockerppc64le:
 	mkdir -p java/target
-	docker run --rm --name rocksdb_linux_ppc64le-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos7_ppc64le-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+	docker run --rm --name rocksdb_linux_ppc64le-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos7_ppc64le-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+
+rocksdbjavastaticdockerarm64v8:
+	mkdir -p java/target
+	docker run --rm --name rocksdb_linux_arm64v8-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:centos7_arm64v8-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+
+rocksdbjavastaticdockerx86musl:
+	mkdir -p java/target
+	docker run --rm --name rocksdb_linux_x86-musl-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:alpine3_x86-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+
+rocksdbjavastaticdockerx86_64musl:
+	mkdir -p java/target
+	docker run --rm --name rocksdb_linux_x64-musl-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:alpine3_x64-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+
+rocksdbjavastaticdockerppc64lemusl:
+	mkdir -p java/target
+	docker run --rm --name rocksdb_linux_ppc64le-musl-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:alpine3_ppc64le-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh
+
+rocksdbjavastaticdockerarm64v8musl:
+	mkdir -p java/target
+	docker run --rm --name rocksdb_linux_arm64v8-musl-be --attach stdin --attach stdout --attach stderr --volume `pwd`:/rocksdb-host:ro --volume /rocksdb-local-build --volume `pwd`/java/target:/rocksdb-java-target --env DEBUG_LEVEL=$(DEBUG_LEVEL) evolvedbinary/rocksjava:alpine3_arm64v8-be /rocksdb-host/java/crossbuild/docker-build-linux-centos.sh

 rocksdbjavastaticpublish: rocksdbjavastaticrelease rocksdbjavastaticpublishcentral

@@ -1884,6 +2000,8 @@ rocksdbjavastaticpublishcentral:
 	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-sources.jar -Dclassifier=sources
 	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-linux64.jar -Dclassifier=linux64
 	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-linux32.jar -Dclassifier=linux32
+	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-linux64-musl.jar -Dclassifier=linux64-musl
+	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-linux32-musl.jar -Dclassifier=linux32-musl
 	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-osx.jar -Dclassifier=osx
 	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH)-win64.jar -Dclassifier=win64
 	mvn gpg:sign-and-deploy-file -Durl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=sonatype-nexus-staging -DpomFile=java/rocksjni.pom -Dfile=java/target/rocksdbjni-$(ROCKSDB_MAJOR).$(ROCKSDB_MINOR).$(ROCKSDB_PATCH).jar
@@ -1937,6 +2055,7 @@ jtest_run:

 jtest: rocksdbjava
 	cd java;$(MAKE) sample;$(MAKE) test;
+	python tools/check_all_python.py # TODO peterd: find a better place for this check in CI targets

 jdb_bench:
 	cd java;$(MAKE) db_bench;
@@ -1984,6 +2103,9 @@ endif
 .cc.o:
 	$(AM_V_CC)$(CXX) $(CXXFLAGS) -c $< -o $@ $(COVERAGEFLAGS)

+.cpp.o:
+	$(AM_V_CC)$(CXX) $(CXXFLAGS) -c $< -o $@ $(COVERAGEFLAGS)
+
 .c.o:
 	$(AM_V_CC)$(CC) $(CFLAGS) -c $< -o $@
 endif
@@ -1991,9 +2113,13 @@ endif
 #  	Source files dependencies detection
 # ---------------------------------------------------------------------------

-all_sources = $(LIB_SOURCES) $(MAIN_SOURCES) $(MOCK_LIB_SOURCES) $(TOOL_LIB_SOURCES) $(BENCH_LIB_SOURCES) $(TEST_LIB_SOURCES) $(ANALYZER_LIB_SOURCES)
+all_sources = $(LIB_SOURCES) $(MAIN_SOURCES) $(MOCK_LIB_SOURCES) $(TOOL_LIB_SOURCES) $(BENCH_LIB_SOURCES) $(TEST_LIB_SOURCES) $(ANALYZER_LIB_SOURCES) $(STRESS_LIB_SOURCES)
 DEPFILES = $(all_sources:.cc=.cc.d)

+ifeq ($(USE_FOLLY_DISTRIBUTED_MUTEX),1)
+  DEPFILES += $(FOLLY_SOURCES:.cpp=.cpp.d)
+endif
+
 # Add proper dependency support so changing a .h file forces a .cc file to
 # rebuild.

@@ -2003,6 +2129,10 @@ DEPFILES = $(all_sources:.cc=.cc.d)
 	@$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) \
 	  -MM -MT'$@' -MT'$(<:.cc=.o)' "$<" -o '$@'

+%.cpp.d: %.cpp
+	@$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) \
+	  -MM -MT'$@' -MT'$(<:.cpp=.o)' "$<" -o '$@'
+
 ifeq ($(HAVE_POWER8),1)
 DEPFILES_C = $(LIB_SOURCES_C:.c=.c.d)
 DEPFILES_ASM = $(LIB_SOURCES_ASM:.S=.S.d)
@@ -9,11 +9,11 @@ It is built on earlier work on [LevelDB](https://github.com/google/leveldb) by S
 and Jeff Dean (jeff@google.com)

 This code is a library that forms the core building block for a fast
-key value server, especially suited for storing data on flash drives.
+key-value server, especially suited for storing data on flash drives.
 It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs
 between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF)
 and Space-Amplification-Factor (SAF). It has multi-threaded compactions,
-making it specially suitable for storing multiple terabytes of data in a
+making it especially suitable for storing multiple terabytes of data in a
 single database.

 Start with example usage here: https://github.com/facebook/rocksdb/tree/master/examples
@@ -96,3 +96,9 @@ LzLabs is using RocksDB as a storage engine in their multi-database distributed

 ## IOTA Foundation
 [IOTA Foundation](https://www.iota.org/) is using RocksDB in the [IOTA Reference Implementation (IRI)](https://github.com/iotaledger/iri) to store the local state of the Tangle. The Tangle is the first open-source distributed ledger powering the future of the Internet of Things.
+ 
+## Avrio Project
+ [Avrio Project](http://avrio-project.github.io/avrio.network/) is using RocksDB in [Avrio ](https://github.com/avrio-project/avrio) to store blocks, account balances and data and other blockchain-releated data. Avrio is a multiblockchain decentralized cryptocurrency empowering monetary transactions.
+ 
+## Crux
+[Crux](https://github.com/juxt/crux) is a document database that uses RocksDB for local [EAV](https://en.wikipedia.org/wiki/Entity%E2%80%93attribute%E2%80%93value_model) index storage to enable point-in-time bitemporal Datalog queries. The "unbundled" architecture uses Kafka to provide horizontal scalability.
@@ -17,6 +17,13 @@ environment:
  ZSTD_INCLUDE: $(ZSTD_HOME)\lib;$(ZSTD_HOME)\lib\dictBuilder
  ZSTD_LIB_DEBUG: $(ZSTD_HOME)\build\VS2010\bin\x64_Debug\libzstd_static.lib
  ZSTD_LIB_RELEASE: $(ZSTD_HOME)\build\VS2010\bin\x64_Release\libzstd_static.lib
+  matrix:
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+      CMAKE_GENERATOR: Visual Studio 14 Win64
+      DEV_ENV: C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\devenv.com
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      CMAKE_GENERATOR: Visual Studio 15 Win64
+      DEV_ENV: C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\devenv.com

 install:
  - md %THIRDPARTY_HOME%
@@ -27,7 +34,7 @@ install:
  - cd snappy-1.1.7
  - mkdir build
  - cd build
-  - cmake -DCMAKE_GENERATOR_PLATFORM=x64 ..
+  - cmake -G "%CMAKE_GENERATOR%" ..
  - msbuild Snappy.sln /p:Configuration=Debug /p:Platform=x64
  - msbuild Snappy.sln /p:Configuration=Release /p:Platform=x64
  - echo "Building LZ4 dependency..."
@@ -35,7 +42,7 @@ install:
  - curl -fsSL -o lz4-1.8.3.zip https://github.com/lz4/lz4/archive/v1.8.3.zip
  - unzip lz4-1.8.3.zip
  - cd lz4-1.8.3\visual\VS2010
-  - ps: $CMD="C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\devenv.com"; & $CMD lz4.sln /upgrade
+  - ps: $CMD="$Env:DEV_ENV"; & $CMD lz4.sln /upgrade
  - msbuild lz4.sln /p:Configuration=Debug /p:Platform=x64
  - msbuild lz4.sln /p:Configuration=Release /p:Platform=x64
  - echo "Building ZStd dependency..."
@@ -43,15 +50,16 @@ install:
  - curl -fsSL -o zstd-1.4.0.zip https://github.com/facebook/zstd/archive/v1.4.0.zip
  - unzip zstd-1.4.0.zip
  - cd zstd-1.4.0\build\VS2010
-  - ps: $CMD="C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\devenv.com"; & $CMD zstd.sln /upgrade
+  - ps: $CMD="$Env:DEV_ENV"; & $CMD zstd.sln /upgrade
  - msbuild zstd.sln /p:Configuration=Debug /p:Platform=x64
  - msbuild zstd.sln /p:Configuration=Release /p:Platform=x64

 before_build:
  - md %APPVEYOR_BUILD_FOLDER%\build
  - cd %APPVEYOR_BUILD_FOLDER%\build
-  - cmake -G "Visual Studio 15 Win64" -DOPTDBG=1 -DPORTABLE=1 -DSNAPPY=1 -DLZ4=1 -DZSTD=1 -DXPRESS=1 -DJNI=1 ..
+  - cmake -G "%CMAKE_GENERATOR%" -DCMAKE_BUILD_TYPE=Debug -DOPTDBG=1 -DPORTABLE=1 -DSNAPPY=1 -DLZ4=1 -DZSTD=1 -DXPRESS=1 -DJNI=1 ..
  - cd ..
+
 build:
  project: build\rocksdb.sln
  parallel: true
@@ -60,7 +68,7 @@ build:
 test:

 test_script:
-  - ps: build_tools\run_ci_db_test.ps1 -SuiteRun db_basic_test,db_test2,db_test,env_basic_test,env_test -Concurrency 8
+  - ps: build_tools\run_ci_db_test.ps1 -SuiteRun db_basic_test,db_test2,db_test,env_basic_test,env_test,db_merge_operand_test -Concurrency 8

 on_failure:
  - cmd: 7z a build-failed.zip %APPVEYOR_BUILD_FOLDER%\build\ && appveyor PushArtifact build-failed.zip
@@ -3,13 +3,36 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals
+try:
+    from builtins import str
+except ImportError:
+    from __builtin__ import str
 from targets_builder import TARGETSBuilder
+import json
 import os
 import fnmatch
 import sys

 from util import ColorString

+# This script generates TARGETS file for Buck.
+# Buck is a build tool specifying dependencies among different build targets.
+# User can pass extra dependencies as a JSON object via command line, and this
+# script can include these dependencies in the generate TARGETS file.
+# Usage:
+# $python buckifier/buckify_rocksdb.py
+# (This generates a TARGET file without user-specified dependency for unit
+# tests.)
+# $python buckifier/buckify_rocksdb.py \
+#        '{"fake": { \
+#                      "extra_deps": [":test_dep", "//fakes/module:mock1"],  \
+#                      "extra_compiler_flags": ["-DROCKSDB_LITE", "-Os"], \
+#                  } \
+#         }'
+# (Generated TARGETS file has test_dep and mock1 as dependencies for RocksDB
+# unit tests, and will use the extra_compiler_flags to compile the unit test
+# source.)
+
 # tests to export as libraries for inclusion in other projects
 _EXPORTED_TEST_LIBS = ["env_basic_test"]

@@ -86,8 +109,32 @@ def get_tests(repo_path):
    return tests


+# Parse extra dependencies passed by user from command line
+def get_dependencies():
+    deps_map = {
+        '': {
+            'extra_deps': [],
+            'extra_compiler_flags': []
+        }
+    }
+    if len(sys.argv) < 2:
+        return deps_map
+
+    def encode_dict(data):
+        rv = {}
+        for k, v in data.items():
+            if isinstance(v, dict):
+                v = encode_dict(v)
+            rv[k] = v
+        return rv
+    extra_deps = json.loads(sys.argv[1], object_hook=encode_dict)
+    for target_alias, deps in extra_deps.items():
+        deps_map[target_alias] = deps
+    return deps_map
+
+
 # Prepare TARGETS file for buck
-def generate_targets(repo_path):
+def generate_targets(repo_path, deps_map):
    print(ColorString.info("Generating TARGETS"))
    # parsed src.mk file
    src_mk = parse_src_mk(repo_path)
@@ -120,25 +167,41 @@ def generate_targets(repo_path):
        src_mk.get("ANALYZER_LIB_SOURCES", []) +
        ["test_util/testutil.cc"],
        [":rocksdb_lib"])
+    # rocksdb_stress_lib
+    TARGETS.add_library(
+        "rocksdb_stress_lib",
+        src_mk.get("ANALYZER_LIB_SOURCES", [])
+        + src_mk.get('STRESS_LIB_SOURCES', [])
+        + ["test_util/testutil.cc"],
+        [":rocksdb_lib"])

+    print("Extra dependencies:\n{0}".format(str(deps_map)))
    # test for every test we found in the Makefile
-    for test in sorted(tests):
-        match_src = [src for src in cc_files if ("/%s.c" % test) in src]
-        if len(match_src) == 0:
-            print(ColorString.warning("Cannot find .cc file for %s" % test))
-            continue
-        elif len(match_src) > 1:
-            print(ColorString.warning("Found more than one .cc for %s" % test))
-            print(match_src)
-            continue
+    for target_alias, deps in deps_map.items():
+        for test in sorted(tests):
+            match_src = [src for src in cc_files if ("/%s.c" % test) in src]
+            if len(match_src) == 0:
+                print(ColorString.warning("Cannot find .cc file for %s" % test))
+                continue
+            elif len(match_src) > 1:
+                print(ColorString.warning("Found more than one .cc for %s" % test))
+                print(match_src)
+                continue

-        assert(len(match_src) == 1)
-        is_parallel = tests[test]
-        TARGETS.register_test(test, match_src[0], is_parallel)
+            assert(len(match_src) == 1)
+            is_parallel = tests[test]
+            test_target_name = \
+                test if not target_alias else test + "_" + target_alias
+            TARGETS.register_test(
+                test_target_name,
+                match_src[0],
+                is_parallel,
+                deps['extra_deps'],
+                deps['extra_compiler_flags'])

-        if test in _EXPORTED_TEST_LIBS:
-            test_library = "%s_lib" % test
-            TARGETS.add_library(test_library, match_src, [":rocksdb_test_lib"])
+            if test in _EXPORTED_TEST_LIBS:
+                test_library = "%s_lib" % test_target_name
+                TARGETS.add_library(test_library, match_src, [":rocksdb_test_lib"])
    TARGETS.flush_tests()

    print(ColorString.info("Generated TARGETS Summary:"))
@@ -163,8 +226,9 @@ def exit_with_error(msg):


 def main():
+    deps_map = get_dependencies()
    # Generate TARGETS file for buck
-    ok = generate_targets(get_rocksdb_path())
+    ok = generate_targets(get_rocksdb_path(), deps_map)
    if not ok:
        exit_with_error("Failed to generate TARGETS files")

@@ -3,6 +3,12 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals
+try:
+    from builtins import object
+    from builtins import str
+except ImportError:
+    from __builtin__ import object
+    from __builtin__ import str
 import targets_cfg

 def pretty_list(lst, indent=8):
@@ -18,7 +24,7 @@ def pretty_list(lst, indent=8):
    return res


-class TARGETSBuilder:
+class TARGETSBuilder(object):
    def __init__(self, path):
        self.path = path
        self.targets_file = open(path, 'w')
@@ -51,14 +57,21 @@ class TARGETSBuilder:
            pretty_list(deps)))
        self.total_bin = self.total_bin + 1

-    def register_test(self, test_name, src, is_parallel):
+    def register_test(self,
+                      test_name,
+                      src,
+                      is_parallel,
+                      extra_deps,
+                      extra_compiler_flags):
        exec_mode = "serial"
        if is_parallel:
            exec_mode = "parallel"
        self.tests_cfg += targets_cfg.test_cfg_template % (
            test_name,
            str(src),
-            str(exec_mode))
+            str(exec_mode),
+            extra_deps,
+            extra_compiler_flags)

        self.total_test = self.total_test + 1

@@ -3,7 +3,13 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals
-rocksdb_target_header = """load("@fbcode_macros//build_defs:auto_headers.bzl", "AutoHeaders")
+
+rocksdb_target_header = """# This file \100generated by `python buckifier/buckify_rocksdb.py`
+# --> DO NOT EDIT MANUALLY <--
+# This file is a Facebook-specific integration for buck builds, so can
+# only be validated by Facebook employees.
+#
+load("@fbcode_macros//build_defs:auto_headers.bzl", "AutoHeaders")
 load("@fbcode_macros//build_defs:cpp_library.bzl", "cpp_library")
 load(":defs.bzl", "test_binary")

@@ -26,6 +32,7 @@ ROCKSDB_EXTERNAL_DEPS = [
    ("lz4", None, "lz4"),
    ("zstd", None),
    ("tbb", None),
+    ("liburing", None, "uring"),
    ("googletest", None, "gtest"),
 ]

@@ -46,6 +53,7 @@ ROCKSDB_OS_PREPROCESSOR_FLAGS = [
            "-DROCKSDB_PTHREAD_ADAPTIVE_MUTEX",
            "-DROCKSDB_RANGESYNC_PRESENT",
            "-DROCKSDB_SCHED_GETCPU_PRESENT",
+            "-DROCKSDB_IOURING_PRESENT",
            "-DHAVE_SSE42",
            "-DNUMA",
        ],
@@ -70,6 +78,7 @@ ROCKSDB_PREPROCESSOR_FLAGS = [
    "-DZSTD_STATIC_LINKING_ONLY",
    "-DGFLAGS=gflags",
    "-DTBB",
+    "-DLIBURING",

    # Added missing flags from output of build_detect_platform
    "-DROCKSDB_BACKTRACE",
@@ -140,11 +149,13 @@ test_cfg_template = """    [
        "%s",
        "%s",
        "%s",
+        %s,
+        %s,
    ],
 """

 unittests_template = """
-# [test_name, test_src, test_type]
+# [test_name, test_src, test_type, extra_deps, extra_compiler_flags]
 ROCKS_TESTS = [
 %s]

@@ -153,6 +164,8 @@ ROCKS_TESTS = [
 # will not be included.
 [
    test_binary(
+        extra_compiler_flags = extra_compiler_flags,
+        extra_deps = extra_deps,
        parallelism = parallelism,
        rocksdb_arch_preprocessor_flags = ROCKSDB_ARCH_PREPROCESSOR_FLAGS,
        rocksdb_compiler_flags = ROCKSDB_COMPILER_FLAGS,
@@ -163,7 +176,7 @@ ROCKS_TESTS = [
        test_cc = test_cc,
        test_name = test_name,
    )
-    for test_name, test_cc, parallelism in ROCKS_TESTS
+    for test_name, test_cc, parallelism, extra_deps, extra_compiler_flags in ROCKS_TESTS
    if not is_opt_mode
 ]
 """
@@ -6,11 +6,16 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals
+try:
+    from builtins import object
+except ImportError:
+    from __builtin__ import object
 import subprocess
+import sys
 import os
 import time

-class ColorString:
+class ColorString(object):
    """ Generate colorful strings on terminal """
    HEADER = '\033[95m'
    BLUE = '\033[94m'
@@ -21,7 +26,13 @@ class ColorString:

    @staticmethod
    def _make_color_str(text, color):
-        return "".join([color, text.encode('utf-8'), ColorString.ENDC])
+        # In Python2, default encoding for unicode string is ASCII
+        if sys.version_info.major <= 2:
+            return "".join(
+                [color, text.encode('utf-8'), ColorString.ENDC])
+        # From Python3, default encoding for unicode string is UTF-8
+        return "".join(
+            [color, text, ColorString.ENDC])

    @staticmethod
    def ok(text):
@@ -1,377 +0,0 @@
-<?php
-// Copyright 2004-present Facebook. All Rights Reserved.
-//  This source code is licensed under both the GPLv2 (found in the
-//  COPYING file in the root directory) and Apache 2.0 License
-//  (found in the LICENSE.Apache file in the root directory).
-
-// Name of the environment variables which need to be set by the entity which
-// triggers continuous runs so that code at the end of the file gets executed
-// and Sandcastle run starts.
-const ENV_POST_RECEIVE_HOOK = "POST_RECEIVE_HOOK";
-const ENV_HTTPS_APP_VALUE = "HTTPS_APP_VALUE";
-const ENV_HTTPS_TOKEN_VALUE = "HTTPS_TOKEN_VALUE";
-
-const PRIMARY_TOKEN_FILE = '/home/krad/.sandcastle';
-const CONT_RUN_ALIAS = "leveldb";
-
-//////////////////////////////////////////////////////////////////////
-/*  Run tests in sandcastle */
-function postURL($diffID, $url) {
-  assert(strlen($diffID) > 0);
-  assert(is_numeric($diffID));
-  assert(strlen($url) > 0);
-
-  $cmd_args = array(
-    'diff_id' => (int)$diffID,
-    'name' => sprintf(
-      'click here for sandcastle tests for D%d',
-      (int)$diffID
-    ),
-    'link' => $url
-  );
-  $cmd = 'echo ' . escapeshellarg(json_encode($cmd_args))
-         . ' | arc call-conduit differential.updateunitresults';
-
-  shell_exec($cmd);
-}
-
-function buildUpdateTestStatusCmd($diffID, $test, $status) {
-  assert(strlen($diffID) > 0);
-  assert(is_numeric($diffID));
-  assert(strlen($test) > 0);
-  assert(strlen($status) > 0);
-
-  $cmd_args = array(
-    'diff_id' => (int)$diffID,
-    'name' => $test,
-    'result' => $status
-  );
-
-  $cmd = 'echo ' . escapeshellarg(json_encode($cmd_args))
-         . ' | arc call-conduit differential.updateunitresults';
-
-  return $cmd;
-}
-
-function updateTestStatus($diffID, $test) {
-  assert(strlen($diffID) > 0);
-  assert(is_numeric($diffID));
-  assert(strlen($test) > 0);
-
-  shell_exec(buildUpdateTestStatusCmd($diffID, $test, "waiting"));
-}
-
-function getSteps($applyDiff, $diffID, $username, $test) {
-  assert(strlen($username) > 0);
-  assert(strlen($test) > 0);
-
-  if ($applyDiff) {
-    assert(strlen($diffID) > 0);
-    assert(is_numeric($diffID));
-
-    $arcrc_content = (PHP_OS == "Darwin" ?
-        exec("cat ~/.arcrc | gzip -f | base64") :
-            exec("cat ~/.arcrc | gzip -f | base64 -w0"));
-    assert(strlen($arcrc_content) > 0);
-
-    // Sandcastle machines don't have arc setup. We copy the user certificate
-    // and authenticate using that in Sandcastle.
-    $setup = array(
-      "name" => "Setup arcrc",
-      "shell" => "echo " . escapeshellarg($arcrc_content) . " | base64 --decode"
-                 . " | gzip -d > ~/.arcrc",
-      "user" => "root"
-    );
-
-    // arc demands certain permission on its config.
-    // also fix the sticky bit issue in sandcastle
-    $fix_permission = array(
-      "name" => "Fix environment",
-      "shell" => "chmod 600 ~/.arcrc && chmod +t /dev/shm",
-      "user" => "root"
-    );
-
-    // Construct the steps in the order of execution.
-    $steps[] = $setup;
-    $steps[] = $fix_permission;
-  }
-
-  // fbcode is a sub-repo. We cannot patch until we add it to ignore otherwise
-  // Git thinks it is an uncommitted change.
-  $fix_git_ignore = array(
-    "name" => "Fix git ignore",
-    "shell" => "echo fbcode >> .git/info/exclude",
-    "user" => "root"
-  );
-
-  // This fixes "FATAL: ThreadSanitizer can not mmap the shadow memory"
-  // Source:
-  // https://github.com/google/sanitizers/wiki/ThreadSanitizerCppManual#FAQ
-  $fix_kernel_issue = array(
-    "name" => "Fix kernel issue with tsan",
-    "shell" => "echo 2 >/proc/sys/kernel/randomize_va_space",
-    "user" => "root"
-  );
-
-  $steps[] = $fix_git_ignore;
-  $steps[] = $fix_kernel_issue;
-
-  // This will be the command used to execute particular type of tests.
-  $cmd = "";
-
-  if ($applyDiff) {
-    // Patch the code (keep your fingures crossed).
-    $patch = array(
-      "name" => "Patch " . $diffID,
-      "shell" => "arc --arcrc-file ~/.arcrc "
-                  . "patch --nocommit --diff " . escapeshellarg($diffID),
-      "user" => "root"
-    );
-
-    $steps[] = $patch;
-
-    updateTestStatus($diffID, $test);
-    $cmd = buildUpdateTestStatusCmd($diffID, $test, "running") . "; ";
-  }
-
-  // Run the actual command.
-  $cmd = $cmd . "J=$(nproc) ./build_tools/precommit_checker.py " .
-           escapeshellarg($test) . "; exit_code=$?; ";
-
-  if ($applyDiff) {
-    $cmd = $cmd . "([[ \$exit_code -eq 0 ]] &&"
-                . buildUpdateTestStatusCmd($diffID, $test, "pass") . ")"
-                . "||" . buildUpdateTestStatusCmd($diffID, $test, "fail")
-                . "; ";
-  }
-
-  // shell command to sort the tests based on exit code and print
-  // the output of the log files.
-  $cat_sorted_logs = "
-    while read code log_file;
-      do echo \"################ cat \$log_file [exit_code : \$code] ################\";
-      cat \$log_file;
-    done < <(tail -n +2 LOG | sort -k7,7n -k4,4gr | awk '{print \$7,\$NF}')";
-
-  // Shell command to cat all log files
-  $cat_all_logs = "for f in `ls t/!(run-*)`; do echo \$f;cat \$f; done";
-
-  // If LOG file exist use it to cat log files sorted by exit code, otherwise
-  // cat everything
-  $logs_cmd = "if [ -f LOG ]; then {$cat_sorted_logs}; else {$cat_all_logs}; fi";
-
-  $cmd = $cmd . " cat /tmp/precommit-check.log"
-              . "; shopt -s extglob; {$logs_cmd}"
-              . "; shopt -u extglob; [[ \$exit_code -eq 0 ]]";
-  assert(strlen($cmd) > 0);
-
-  $run_test = array(
-    "name" => "Run " . $test,
-    "shell" => $cmd,
-    "user" => "root",
-    "parser" => "python build_tools/error_filter.py " . escapeshellarg($test),
-  );
-
-  $steps[] = $run_test;
-
-  if ($applyDiff) {
-    // Clean up the user arc config we are using.
-    $cleanup = array(
-      "name" => "Arc cleanup",
-      "shell" => "rm -f ~/.arcrc",
-      "user" => "root"
-    );
-
-    $steps[] = $cleanup;
-  }
-
-  assert(count($steps) > 0);
-  return $steps;
-}
-
-function getSandcastleConfig() {
-  $sandcastle_config = array();
-
-  $cwd = getcwd();
-  $cwd_token_file = "{$cwd}/.sandcastle";
-  // This is a case when we're executed from a continuous run. Fetch the values
-  // from the environment.
-  if (getenv(ENV_POST_RECEIVE_HOOK)) {
-    $sandcastle_config[0] = getenv(ENV_HTTPS_APP_VALUE);
-    $sandcastle_config[1] = getenv(ENV_HTTPS_TOKEN_VALUE);
-  } else {
-    // This is a typical `[p]arc diff` case. Fetch the values from the specific
-    // configuration files.
-    for ($i = 0; $i < 50; $i++) {
-      if (file_exists(PRIMARY_TOKEN_FILE) ||
-          file_exists($cwd_token_file)) {
-        break;
-      }
-      // If we failed to fetch the tokens, sleep for 0.2 second and try again
-      usleep(200000);
-    }
-    assert(file_exists(PRIMARY_TOKEN_FILE) ||
-           file_exists($cwd_token_file));
-
-    // Try the primary location first, followed by a secondary.
-    if (file_exists(PRIMARY_TOKEN_FILE)) {
-      $cmd = 'cat ' . PRIMARY_TOKEN_FILE;
-    } else {
-      $cmd = 'cat ' . escapeshellarg($cwd_token_file);
-    }
-
-    assert(strlen($cmd) > 0);
-    $sandcastle_config = explode(':', rtrim(shell_exec($cmd)));
-  }
-
-  // In this case be very explicit about the implications.
-  if (count($sandcastle_config) != 2) {
-    echo "Sandcastle configuration files don't contain valid information " .
-         "or the necessary environment variables aren't defined. Unable " .
-         "to validate the code changes.";
-    exit(1);
-  }
-
-  assert(strlen($sandcastle_config[0]) > 0);
-  assert(strlen($sandcastle_config[1]) > 0);
-  assert(count($sandcastle_config) > 0);
-
-  return $sandcastle_config;
-}
-
-// This function can be called either from `[p]arc diff` command or during
-// the Git post-receive hook.
- function startTestsInSandcastle($applyDiff, $workflow, $diffID) {
-  // Default options don't terminate on failure, but that's what we want. In
-  // the current case we use assertions intentionally as "terminate on failure
-  // invariants".
-  assert_options(ASSERT_BAIL, true);
-
-  // In case of a diff we'll send notificatios to the author. Else it'll go to
-  // the entire team because failures indicate that build quality has regressed.
-  $username = $applyDiff ? exec("whoami") : CONT_RUN_ALIAS;
-  assert(strlen($username) > 0);
-
-  if ($applyDiff) {
-    assert($workflow);
-    assert(strlen($diffID) > 0);
-    assert(is_numeric($diffID));
-  }
-
-  // List of tests we want to run in Sandcastle.
-  $tests = array("unit", "unit_non_shm", "unit_481", "clang_unit", "tsan",
-                 "asan", "lite_test", "valgrind", "release", "release_481",
-                 "clang_release", "clang_analyze", "code_cov",
-                 "java_build", "no_compression", "unity", "ubsan");
-
-  $send_email_template = array(
-    'type' => 'email',
-    'triggers' => array('fail'),
-    'emails' => array($username . '@fb.com'),
-  );
-
-  // Construct a job definition for each test and add it to the master plan.
-  foreach ($tests as $test) {
-    $stepName = "RocksDB diff " . $diffID . " test " . $test;
-
-    if (!$applyDiff) {
-      $stepName = "RocksDB continuous integration test " . $test;
-    }
-
-    $arg[] = array(
-      "name" => $stepName,
-      "report" => array($send_email_template),
-      "steps" => getSteps($applyDiff, $diffID, $username, $test)
-    );
-  }
-
-  // We cannot submit the parallel execution master plan to Sandcastle and
-  // need supply the job plan as a determinator. So we construct a small job
-  // that will spit out the master job plan which Sandcastle will parse and
-  // execute. Why compress the job definitions? Otherwise we run over the max
-  // string size.
-  $cmd = "echo " . base64_encode(json_encode($arg))
-         . (PHP_OS == "Darwin" ?
-             " | gzip -f | base64" :
-                 " | gzip -f | base64 -w0");
-  assert(strlen($cmd) > 0);
-
-  $arg_encoded = shell_exec($cmd);
-  assert(strlen($arg_encoded) > 0);
-
-  $runName = "Run diff " . $diffID . "for user " . $username;
-
-  if (!$applyDiff) {
-    $runName = "RocksDB continuous integration build and test run";
-  }
-
-  $command = array(
-    "name" => $runName,
-    "steps" => array()
-  );
-
-  $command["steps"][] = array(
-    "name" => "Generate determinator",
-    "shell" => "echo " . $arg_encoded . " | base64 --decode | gzip -d"
-               . " | base64 --decode",
-    "determinator" => true,
-    "user" => "root"
-  );
-
-  // Submit to Sandcastle.
-  $url = 'https://interngraph.intern.facebook.com/sandcastle/create';
-
-  $job = array(
-    'command' => 'SandcastleUniversalCommand',
-    'args' => $command,
-    'capabilities' => array(
-      'vcs' => 'rocksdb-int-git',
-      'type' => 'lego',
-    ),
-    'hash' => 'origin/master',
-    'user' => $username,
-    'alias' => 'rocksdb-precommit',
-    'tags' => array('rocksdb'),
-    'description' => 'Rocksdb precommit job',
-  );
-
-  // Fetch the configuration necessary to submit a successful HTTPS request.
-  $sandcastle_config = getSandcastleConfig();
-
-  $app = $sandcastle_config[0];
-  $token = $sandcastle_config[1];
-
-  $cmd = 'curl -s -k '
-          . ' -F app=' . escapeshellarg($app)
-          . ' -F token=' . escapeshellarg($token)
-          . ' -F job=' . escapeshellarg(json_encode($job))
-          .' ' . escapeshellarg($url);
-
-  $output = shell_exec($cmd);
-  assert(strlen($output) > 0);
-
-  // Extract Sandcastle URL from the response.
-  preg_match('/url": "(.+)"/', $output, $sandcastle_url);
-
-  assert(count($sandcastle_url) > 0, "Unable to submit Sandcastle request.");
-  assert(strlen($sandcastle_url[1]) > 0, "Unable to extract Sandcastle URL.");
-
-  if ($applyDiff) {
-    echo "\nSandcastle URL: " . $sandcastle_url[1] . "\n";
-    // Ask Phabricator to display it on the diff UI.
-    postURL($diffID, $sandcastle_url[1]);
-  } else {
-    echo "Continuous integration started Sandcastle tests. You can look at ";
-    echo "the progress at:\n" . $sandcastle_url[1] . "\n";
-  }
-}
-
-// Continuous run cript will set the environment variable and based on that
-// we'll trigger the execution of tests in Sandcastle. In that case we don't
-// need to apply any diffs and there's no associated workflow either.
-if (getenv(ENV_POST_RECEIVE_HOOK)) {
-  startTestsInSandcastle(
-    false /* $applyDiff */,
-    NULL /* $workflow */,
-    NULL /* $diffID */);
-}
@@ -56,10 +56,10 @@ if [ -z "$ROCKSDB_NO_FBCODE" -a -d /mnt/gvfs/third-party ]; then
    if [ -n "$ROCKSDB_FBCODE_BUILD_WITH_481" ]; then
      # we need this to build with MySQL. Don't use for other purposes.
      source "$PWD/build_tools/fbcode_config4.8.1.sh"
-    elif [ -n "$ROCKSDB_FBCODE_BUILD_WITH_PLATFORM007" ]; then
-      source "$PWD/build_tools/fbcode_config_platform007.sh"
-    else
+    elif [ -n "$ROCKSDB_FBCODE_BUILD_WITH_5xx" ]; then
      source "$PWD/build_tools/fbcode_config.sh"
+    else
+      source "$PWD/build_tools/fbcode_config_platform007.sh"
    fi
 fi

@@ -150,6 +150,22 @@ case "$TARGET_OS" in
            PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -latomic"
        fi
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread -lrt"
+        # check for liburing
+        $CXX $CFLAGS -x c++ - -luring -o /dev/null 2>/dev/null  <<EOF
+          #include <liburing.h>
+          int main() {
+            struct io_uring ring;
+            io_uring_queue_init(1, &ring, 0);
+            return 0;
+          }
+EOF
+        if [ "$?" = 0 ]; then
+          PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -luring"
+          COMMON_FLAGS="$COMMON_FLAGS -DROCKSDB_IOURING_PRESENT"
+        fi
+        if test -z "$USE_FOLLY_DISTRIBUTED_MUTEX"; then
+          USE_FOLLY_DISTRIBUTED_MUTEX=1
+        fi
        # PORT_FILES=port/linux/linux_specific.cc
        ;;
    SunOS)
@@ -530,7 +546,7 @@ if test "$USE_HDFS"; then
  JAVA_LDFLAGS="$JAVA_LDFLAGS $HDFS_LDFLAGS"
 fi

-if test -z "$PORTABLE"; then
+if test "0$PORTABLE" -eq 0; then
  if test -n "`echo $TARGET_ARCHITECTURE | grep ^ppc64`"; then
    # Tune for this POWER processor, treating '+' models as base models
    POWER=`LD_SHOW_AUXV=1 /bin/true | grep AT_PLATFORM | grep -E -o power[0-9]+`
@@ -544,16 +560,36 @@ if test -z "$PORTABLE"; then
    COMMON_FLAGS="$COMMON_FLAGS"
  elif [ "$TARGET_OS" == "IOS" ]; then
    COMMON_FLAGS="$COMMON_FLAGS"
-  elif [ "$TARGET_OS" != "AIX" ] && [ "$TARGET_OS" != "SunOS" ]; then
+  elif [ "$TARGET_OS" == "AIX" ] || [ "$TARGET_OS" == "SunOS" ]; then
+    # TODO: Not sure why we don't use -march=native on these OSes
+    if test "$USE_SSE"; then
+      TRY_SSE_ETC="1"
+    fi
+  else
    COMMON_FLAGS="$COMMON_FLAGS -march=native "
-  elif test "$USE_SSE"; then
-    COMMON_FLAGS="$COMMON_FLAGS -msse4.2 -mpclmul"
  fi
-elif test "$USE_SSE"; then
-  COMMON_FLAGS="$COMMON_FLAGS -msse4.2 -mpclmul"
+else
+  # PORTABLE=1
+  if test "$USE_SSE"; then
+    TRY_SSE_ETC="1"
+  fi
 fi

-$CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null <<EOF
+if test "$TRY_SSE_ETC"; then
+  # The USE_SSE flag now means "attempt to compile with widely-available
+  # Intel architecture extensions utilized by specific optimizations in the
+  # source code." It's a qualifier on PORTABLE=1 that means "mostly portable."
+  # It doesn't even really check that your current CPU is compatible.
+  #
+  # SSE4.2 available since nehalem, ca. 2008-2010
+  TRY_SSE42="-msse4.2"
+  # PCLMUL available since westmere, ca. 2010-2011
+  TRY_PCLMUL="-mpclmul"
+  # AVX2 available since haswell, ca. 2013-2015
+  TRY_AVX2="-mavx2"
+fi
+
+$CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS $TRY_SSE42 -x c++ - -o /dev/null 2>/dev/null <<EOF
  #include <cstdint>
  #include <nmmintrin.h>
  int main() {
@@ -562,13 +598,12 @@ $CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null <<EOF
  }
 EOF
 if [ "$?" = 0 ]; then
-  COMMON_FLAGS="$COMMON_FLAGS -DHAVE_SSE42"
+  COMMON_FLAGS="$COMMON_FLAGS $TRY_SSE42 -DHAVE_SSE42"
 elif test "$USE_SSE"; then
  echo "warning: USE_SSE specified but compiler could not use SSE intrinsics, disabling" >&2
-  exit 1
 fi

-$CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null <<EOF
+$CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS $TRY_PCLMUL -x c++ - -o /dev/null 2>/dev/null <<EOF
  #include <cstdint>
  #include <wmmintrin.h>
  int main() {
@@ -580,10 +615,37 @@ $CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null <<EOF
  }
 EOF
 if [ "$?" = 0 ]; then
-  COMMON_FLAGS="$COMMON_FLAGS -DHAVE_PCLMUL"
+  COMMON_FLAGS="$COMMON_FLAGS $TRY_PCLMUL -DHAVE_PCLMUL"
 elif test "$USE_SSE"; then
  echo "warning: USE_SSE specified but compiler could not use PCLMUL intrinsics, disabling" >&2
-  exit 1
+fi
+
+$CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS $TRY_AVX2 -x c++ - -o /dev/null 2>/dev/null <<EOF
+  #include <cstdint>
+  #include <immintrin.h>
+  int main() {
+    const auto a = _mm256_setr_epi32(0, 1, 2, 3, 4, 7, 6, 5);
+    const auto b = _mm256_permutevar8x32_epi32(a, a);
+    (void)b;
+  }
+EOF
+if [ "$?" = 0 ]; then
+  COMMON_FLAGS="$COMMON_FLAGS $TRY_AVX2 -DHAVE_AVX2"
+elif test "$USE_SSE"; then
+  echo "warning: USE_SSE specified but compiler could not use AVX2 intrinsics, disabling" >&2
+fi
+
+$CXX $PLATFORM_CXXFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null <<EOF
+  #include <cstdint>
+  int main() {
+    uint64_t a = 0xffffFFFFffffFFFF;
+    __uint128_t b = __uint128_t(a) * a;
+    a = static_cast<uint64_t>(b >> 64);
+    (void)a;
+  }
+EOF
+if [ "$?" = 0 ]; then
+  COMMON_FLAGS="$COMMON_FLAGS -DHAVE_UINT128_EXTENSION"
 fi

 # iOS doesn't support thread-local storage, but this check would erroneously
@@ -661,3 +723,6 @@ if test -n "$WITH_JEMALLOC_FLAG"; then
  echo "WITH_JEMALLOC_FLAG=$WITH_JEMALLOC_FLAG" >> "$OUTPUT"
 fi
 echo "LUA_PATH=$LUA_PATH" >> "$OUTPUT"
+if test -n "$USE_FOLLY_DISTRIBUTED_MUTEX"; then
+  echo "USE_FOLLY_DISTRIBUTED_MUTEX=$USE_FOLLY_DISTRIBUTED_MUTEX" >> "$OUTPUT"
+fi
@@ -1,137 +0,0 @@
-#!/usr/bin/env bash
-#
-# Copyright (c) 2016, Facebook. All rights reserved.
-#
-# Overall wrapper script for RocksDB continuous builds. The implementation is a
-# trivial pulling scheme. We loop infinitely, check if any new changes have been
-# committed, if yes then trigger a Sandcastle run, and finally go to sleep again
-# for a certain interval.
-#
-
-SRC_GIT_REPO=/data/git/rocksdb-public
-error=0
-
-function log {
-  DATE=`date +%Y-%m-%d:%H:%M:%S`
-  # shellcheck disable=SC2068
-  echo $DATE $@
-}
-
-function log_err {
-  # shellcheck disable=SC2145
-  log "ERROR: $@ Error code: $error."
-}
-
-function update_repo_status {
-  # Update the parent first.
-  pushd $SRC_GIT_REPO
-
-  # This is a fatal error. Something in the environment isn't right and we will
-  # terminate the execution.
-  error=$?
-  if [ ! $error -eq 0 ]; then
-    log_err "Where is $SRC_GIT_REPO?"
-    exit $error
-  fi
-
-  HTTPS_PROXY=fwdproxy:8080 git fetch -f
-
-  error=$?
-  if [ ! $error -eq 0 ]; then
-    log_err "git fetch -f failed."
-    popd
-    return $error
-  fi
-
-  git update-ref refs/heads/master refs/remotes/origin/master
-
-  error=$?
-  if [ ! $error -eq 0 ]; then
-    log_err "git update-ref failed."
-    popd
-    return $error
-  fi
-
-  popd
-
-  # We're back in an instance-specific directory. Get the latest changes.
-  git pull --rebase
-
-  error=$?
-  if [ ! $error -eq 0 ]; then
-    log_err "git pull --rebase failed."
-    return $error
-  fi
-}
-
-#
-# Execution starts here.
-#
-
-# Path to the determinator from the root of the RocksDB repo.
-CONTRUN_DETERMINATOR=./build_tools/RocksDBCommonHelper.php
-
-# Value of the previous commit.
-PREV_COMMIT=
-
-log "Starting to monitor for new RocksDB changes ..."
-log "Running under `pwd` as `whoami`."
-
-# Paranoia. Make sure that we're using the right branch.
-git checkout master
-
-error=$?
-if [ ! $error -eq 0 ]; then
-  log_err "This is not good. Can't checkout master. Bye-bye!"
-  exit 1
-fi
-
-# We'll run forever and let the execution environment terminate us if we'll
-# exceed whatever timeout is set for the job.
-while true;
-do
-  # Get the latest changes committed.
-  update_repo_status
-
-  error=$?
-  if [  $error -eq 0 ]; then
-    LAST_COMMIT=`git log -1 | head -1 | grep commit | awk '{ print $2; }'`
-
-    log "Last commit is '$LAST_COMMIT', previous commit is '$PREV_COMMIT'."
-
-    if [ "$PREV_COMMIT" == "$LAST_COMMIT" ]; then
-      log "There were no changes since the last time I checked. Going to sleep."
-    else
-      if [ ! -z "$LAST_COMMIT" ]; then
-        log "New code has been committed or previous commit not known. " \
-            "Will trigger the tests."
-
-        PREV_COMMIT=$LAST_COMMIT
-        log "Updated previous commit to '$PREV_COMMIT'."
-
-        #
-        # This is where we'll trigger the Sandcastle run. The values for
-        # HTTPS_APP_VALUE and HTTPS_APP_VALUE will be set in the container we're
-        # running in.
-        #
-        POST_RECEIVE_HOOK=1 php $CONTRUN_DETERMINATOR
-
-        error=$?
-        if [ $error -eq 0 ]; then
-          log "Sandcastle run successfully triggered."
-        else
-          log_err "Failed to trigger Sandcastle run."
-        fi
-      else
-        log_err "Previous commit not updated. Don't know what the last one is."
-      fi
-    fi
-  else
-    log_err "Getting latest changes failed. Will skip running tests for now."
-  fi
-
-  # Always sleep, even if errors happens while trying to determine the latest
-  # commit. This will prevent us terminating in case of transient errors.
-  log "Will go to sleep for 5 minutes."
-  sleep 5m
-done
@@ -1,19 +1,19 @@
 # Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
-GCC_BASE=/mnt/gvfs/third-party2/gcc/112ec378fec7002ad3e09afde022e656049f7191/5.x/centos7-native/c447969
-CLANG_BASE=/mnt/gvfs/third-party2/llvm-fb/04999bdb3ce81a11073535dcb00b5e13dc1cbaf5/stable/centos7-native/c9f9104
-LIBGCC_BASE=/mnt/gvfs/third-party2/libgcc/92b0c8e5c8eecc71eb042594ce1ab3413799b385/5.x/gcc-5-glibc-2.23/339d858
-GLIBC_BASE=/mnt/gvfs/third-party2/glibc/3d8698d5973ba94f41620a80a67e4457fdf01e90/2.23/gcc-5-glibc-2.23/ca1d1c0
+GCC_BASE=/mnt/gvfs/third-party2/gcc/7331085db891a2ef4a88a48a751d834e8d68f4cb/5.x/centos7-native/c447969
+CLANG_BASE=/mnt/gvfs/third-party2/llvm-fb/1bd23f9917738974ad0ff305aa23eb5f93f18305/9.0.0/centos7-native/c9f9104
+LIBGCC_BASE=/mnt/gvfs/third-party2/libgcc/6ace84e956873d53638c738b6f65f3f469cca74c/5.x/gcc-5-glibc-2.23/339d858
+GLIBC_BASE=/mnt/gvfs/third-party2/glibc/192b0f42d63dcf6210d6ceae387b49af049e6e0c/2.23/gcc-5-glibc-2.23/ca1d1c0
 SNAPPY_BASE=/mnt/gvfs/third-party2/snappy/7f9bdaada18f59bc27ec2b0871eb8a6144343aef/1.1.3/gcc-5-glibc-2.23/9bc6787
-ZLIB_BASE=/mnt/gvfs/third-party2/zlib/22c2d65676fb7c23cfa797c4f6937f38b026f3cf/1.2.8/gcc-5-glibc-2.23/9bc6787
+ZLIB_BASE=/mnt/gvfs/third-party2/zlib/2d9f0b9a4274cc21f61272a9e89bdb859bce8f1f/1.2.8/gcc-5-glibc-2.23/9bc6787
 BZIP2_BASE=/mnt/gvfs/third-party2/bzip2/dc49a21c5fceec6456a7a28a94dcd16690af1337/1.0.6/gcc-5-glibc-2.23/9bc6787
-LZ4_BASE=/mnt/gvfs/third-party2/lz4/907b498203d297947f3bb70b9466f47e100f1873/r131/gcc-5-glibc-2.23/9bc6787
-ZSTD_BASE=/mnt/gvfs/third-party2/zstd/af6628a46758f1a15484a1760cd7294164bc5ba1/1.3.5/gcc-5-glibc-2.23/03859b5
+LZ4_BASE=/mnt/gvfs/third-party2/lz4/0f607f8fc442ea7d6b876931b1898bb573d5e5da/1.9.1/gcc-5-glibc-2.23/9bc6787
+ZSTD_BASE=/mnt/gvfs/third-party2/zstd/ca22bc441a4eb709e9e0b1f9fec9750fed7b31c5/1.4.x/gcc-5-glibc-2.23/03859b5
 GFLAGS_BASE=/mnt/gvfs/third-party2/gflags/0b9929d2588991c65a57168bf88aff2db87c5d48/2.2.0/gcc-5-glibc-2.23/9bc6787
-JEMALLOC_BASE=/mnt/gvfs/third-party2/jemalloc/b1a0e56c1e3e6929813a4331ade3a58ff083afbb/master/gcc-5-glibc-2.23/aa64d6b
-NUMA_BASE=/mnt/gvfs/third-party2/numa/9cbf2460284c669ed19c3ccb200a71f7dd7e53c7/2.0.11/gcc-5-glibc-2.23/9bc6787
-LIBUNWIND_BASE=/mnt/gvfs/third-party2/libunwind/bf3d7497fe4e6d007354f0adffa16ce3003f8338/1.3/gcc-5-glibc-2.23/b443de1
-TBB_BASE=/mnt/gvfs/third-party2/tbb/ff4e0b093534704d8abab678a4fd7f5ea7b094c7/2018_U5/gcc-5-glibc-2.23/9bc6787
-KERNEL_HEADERS_BASE=/mnt/gvfs/third-party2/kernel-headers/b5c4a61a5c483ba24722005ae07895971a2ac707/4.0.9-36_fbk5_2933_gd092e3f/gcc-5-glibc-2.23/da39a3e
-BINUTILS_BASE=/mnt/gvfs/third-party2/binutils/55031de95a2b46c82948743419a603b3d6aefe28/2.29.1/centos7-native/da39a3e
-VALGRIND_BASE=/mnt/gvfs/third-party2/valgrind/f3f697a28122e6bcd513273dd9c1ff23852fc59f/3.13.0/gcc-5-glibc-2.23/9bc6787
+JEMALLOC_BASE=/mnt/gvfs/third-party2/jemalloc/c26f08f47ac35fc31da2633b7da92d6b863246eb/master/gcc-5-glibc-2.23/0c8f76d
+NUMA_BASE=/mnt/gvfs/third-party2/numa/3f3fb57a5ccc5fd21c66416c0b83e0aa76a05376/2.0.11/gcc-5-glibc-2.23/9bc6787
+LIBUNWIND_BASE=/mnt/gvfs/third-party2/libunwind/40c73d874898b386a71847f1b99115d93822d11f/1.4/gcc-5-glibc-2.23/b443de1
+TBB_BASE=/mnt/gvfs/third-party2/tbb/4ce8e8dba77cdbd81b75d6f0c32fd7a1b76a11ec/2018_U5/gcc-5-glibc-2.23/9bc6787
+KERNEL_HEADERS_BASE=/mnt/gvfs/third-party2/kernel-headers/fb251ecd2f5ae16f8671f7014c246e52a748fe0b/4.0.9-36_fbk5_2933_gd092e3f/gcc-5-glibc-2.23/da39a3e
+BINUTILS_BASE=/mnt/gvfs/third-party2/binutils/2e3cb7d119b3cea5f1e738cc13a1ac69f49eb875/2.29.1/centos7-native/da39a3e
+VALGRIND_BASE=/mnt/gvfs/third-party2/valgrind/d42d152a15636529b0861ec493927200ebebca8e/3.15.0/gcc-5-glibc-2.23/9bc6787
 LUA_BASE=/mnt/gvfs/third-party2/lua/f0cd714433206d5139df61659eb7b28b1dea6683/5.2.3/gcc-5-glibc-2.23/65372bd
@@ -1,19 +1,20 @@
 # Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
-GCC_BASE=/mnt/gvfs/third-party2/gcc/6e8e715624fd15256a7970073387793dfcf79b46/7.x/centos7-native/b2ef2b6
-CLANG_BASE=/mnt/gvfs/third-party2/llvm-fb/ef37e1faa1c29782abfac1ae65a291b9b7966f6d/stable/centos7-native/c9f9104
-LIBGCC_BASE=/mnt/gvfs/third-party2/libgcc/c67031f0f739ac61575a061518d6ef5038f99f90/7.x/platform007/5620abc
-GLIBC_BASE=/mnt/gvfs/third-party2/glibc/60d6f124a78798b73944f5ba87c2306ae3460153/2.26/platform007/f259413
+GCC_BASE=/mnt/gvfs/third-party2/gcc/7331085db891a2ef4a88a48a751d834e8d68f4cb/7.x/centos7-native/b2ef2b6
+CLANG_BASE=/mnt/gvfs/third-party2/llvm-fb/963d9aeda70cc4779885b1277484fe7544a04e3e/9.0.0/platform007/9e92d53/
+LIBGCC_BASE=/mnt/gvfs/third-party2/libgcc/6ace84e956873d53638c738b6f65f3f469cca74c/7.x/platform007/5620abc
+GLIBC_BASE=/mnt/gvfs/third-party2/glibc/192b0f42d63dcf6210d6ceae387b49af049e6e0c/2.26/platform007/f259413
 SNAPPY_BASE=/mnt/gvfs/third-party2/snappy/7f9bdaada18f59bc27ec2b0871eb8a6144343aef/1.1.3/platform007/ca4da3d
-ZLIB_BASE=/mnt/gvfs/third-party2/zlib/22c2d65676fb7c23cfa797c4f6937f38b026f3cf/1.2.8/platform007/ca4da3d
+ZLIB_BASE=/mnt/gvfs/third-party2/zlib/2d9f0b9a4274cc21f61272a9e89bdb859bce8f1f/1.2.8/platform007/ca4da3d
 BZIP2_BASE=/mnt/gvfs/third-party2/bzip2/dc49a21c5fceec6456a7a28a94dcd16690af1337/1.0.6/platform007/ca4da3d
-LZ4_BASE=/mnt/gvfs/third-party2/lz4/907b498203d297947f3bb70b9466f47e100f1873/r131/platform007/ca4da3d
-ZSTD_BASE=/mnt/gvfs/third-party2/zstd/3ee276cbacfad3074e3f07bf826ac47f06970f4e/1.3.5/platform007/15a3614
+LZ4_BASE=/mnt/gvfs/third-party2/lz4/0f607f8fc442ea7d6b876931b1898bb573d5e5da/1.9.1/platform007/ca4da3d
+ZSTD_BASE=/mnt/gvfs/third-party2/zstd/ca22bc441a4eb709e9e0b1f9fec9750fed7b31c5/1.4.x/platform007/15a3614
 GFLAGS_BASE=/mnt/gvfs/third-party2/gflags/0b9929d2588991c65a57168bf88aff2db87c5d48/2.2.0/platform007/ca4da3d
-JEMALLOC_BASE=/mnt/gvfs/third-party2/jemalloc/9c910d36d6235cc40e8ff559358f1833452300ca/master/platform007/5b0f53e
-NUMA_BASE=/mnt/gvfs/third-party2/numa/9cbf2460284c669ed19c3ccb200a71f7dd7e53c7/2.0.11/platform007/ca4da3d
-LIBUNWIND_BASE=/mnt/gvfs/third-party2/libunwind/bf3d7497fe4e6d007354f0adffa16ce3003f8338/1.3/platform007/6f3e0a9
-TBB_BASE=/mnt/gvfs/third-party2/tbb/ff4e0b093534704d8abab678a4fd7f5ea7b094c7/2018_U5/platform007/ca4da3d
-KERNEL_HEADERS_BASE=/mnt/gvfs/third-party2/kernel-headers/b5c4a61a5c483ba24722005ae07895971a2ac707/fb/platform007/da39a3e
-BINUTILS_BASE=/mnt/gvfs/third-party2/binutils/92ff90349e2f43ea0a8246d8b1cf17b6869013e3/2.29.1/centos7-native/da39a3e
-VALGRIND_BASE=/mnt/gvfs/third-party2/valgrind/f3f697a28122e6bcd513273dd9c1ff23852fc59f/3.13.0/platform007/ca4da3d
+JEMALLOC_BASE=/mnt/gvfs/third-party2/jemalloc/c26f08f47ac35fc31da2633b7da92d6b863246eb/master/platform007/c26c002
+NUMA_BASE=/mnt/gvfs/third-party2/numa/3f3fb57a5ccc5fd21c66416c0b83e0aa76a05376/2.0.11/platform007/ca4da3d
+LIBUNWIND_BASE=/mnt/gvfs/third-party2/libunwind/40c73d874898b386a71847f1b99115d93822d11f/1.4/platform007/6f3e0a9
+TBB_BASE=/mnt/gvfs/third-party2/tbb/4ce8e8dba77cdbd81b75d6f0c32fd7a1b76a11ec/2018_U5/platform007/ca4da3d
+LIBURING_BASE=/mnt/gvfs/third-party2/liburing/79427253fd0d42677255aacfe6d13bfe63f752eb/20190828/platform007/ca4da3d
+KERNEL_HEADERS_BASE=/mnt/gvfs/third-party2/kernel-headers/fb251ecd2f5ae16f8671f7014c246e52a748fe0b/fb/platform007/da39a3e
+BINUTILS_BASE=/mnt/gvfs/third-party2/binutils/ab9f09bba370e7066cafd4eb59752db93f2e8312/2.29.1/platform007/15a3614
+VALGRIND_BASE=/mnt/gvfs/third-party2/valgrind/d42d152a15636529b0861ec493927200ebebca8e/3.15.0/platform007/ca4da3d
 LUA_BASE=/mnt/gvfs/third-party2/lua/f0cd714433206d5139df61659eb7b28b1dea6683/5.3.4/platform007/5007832
@@ -133,13 +133,16 @@ _TEST_NAME_TO_PARSERS = {
    'lite_test': [CompilerErrorParser, GTestErrorParser],
    'stress_crash': [CompilerErrorParser, DbCrashErrorParser],
    'stress_crash_with_atomic_flush': [CompilerErrorParser, DbCrashErrorParser],
+    'stress_crash_with_txn': [CompilerErrorParser, DbCrashErrorParser],
    'write_stress': [CompilerErrorParser, WriteStressErrorParser],
    'asan': [CompilerErrorParser, GTestErrorParser, AsanErrorParser],
    'asan_crash': [CompilerErrorParser, AsanErrorParser, DbCrashErrorParser],
    'asan_crash_with_atomic_flush': [CompilerErrorParser, AsanErrorParser, DbCrashErrorParser],
+    'asan_crash_with_txn': [CompilerErrorParser, AsanErrorParser, DbCrashErrorParser],
    'ubsan': [CompilerErrorParser, GTestErrorParser, UbsanErrorParser],
    'ubsan_crash': [CompilerErrorParser, UbsanErrorParser, DbCrashErrorParser],
    'ubsan_crash_with_atomic_flush': [CompilerErrorParser, UbsanErrorParser, DbCrashErrorParser],
+    'ubsan_crash_with_txn': [CompilerErrorParser, UbsanErrorParser, DbCrashErrorParser],
    'valgrind': [CompilerErrorParser, GTestErrorParser, ValgrindErrorParser],
    'tsan': [CompilerErrorParser, GTestErrorParser, TsanErrorParser],
    'format_compatible': [CompilerErrorParser, CompatErrorParser],
@@ -86,9 +86,10 @@ else
 fi
 CFLAGS+=" -DTBB"

-# use Intel SSE support for checksum calculations
-export USE_SSE=1
-export PORTABLE=1
+test "$USE_SSE" || USE_SSE=1
+export USE_SSE
+test "$PORTABLE" || PORTABLE=1
+export PORTABLE

 BINUTILS="$BINUTILS_BASE/bin"
 AR="$BINUTILS/ar"
@@ -159,4 +160,6 @@ else
  LUA_LIB=" $LUA_PATH/lib/liblua_pic.a"
 fi

+USE_FOLLY_DISTRIBUTED_MUTEX=1
+
 export CC CXX AR CFLAGS CXXFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED VALGRIND_VER JEMALLOC_LIB JEMALLOC_INCLUDE CLANG_ANALYZER CLANG_SCAN_BUILD LUA_PATH LUA_LIB
@@ -53,9 +53,10 @@ LIBUNWIND="$LIBUNWIND_BASE/lib/libunwind.a"
 TBB_INCLUDE=" -isystem $TBB_BASE/include/"
 TBB_LIBS="$TBB_BASE/lib/libtbb.a"

-# use Intel SSE support for checksum calculations
-export USE_SSE=1
-export PORTABLE=1
+test "$USE_SSE" || USE_SSE=1
+export USE_SSE
+test "$PORTABLE" || PORTABLE=1
+export PORTABLE

 BINUTILS="$BINUTILS_BASE/bin"
 AR="$BINUTILS/ar"
@@ -86,14 +86,24 @@ else
 fi
 CFLAGS+=" -DTBB"

-# use Intel SSE support for checksum calculations
-export USE_SSE=1
-export PORTABLE=1
+# location of LIBURING
+LIBURING_INCLUDE=" -isystem $LIBURING_BASE/include/"
+if test -z $PIC_BUILD; then
+  LIBURING_LIBS="$LIBURING_BASE/lib/liburing.a"
+else
+  LIBURING_LIBS="$LIBURING_BASE/lib/liburing_pic.a"
+fi
+CFLAGS+=" -DLIBURING"
+
+test "$USE_SSE" || USE_SSE=1
+export USE_SSE
+test "$PORTABLE" || PORTABLE=1
+export PORTABLE

 BINUTILS="$BINUTILS_BASE/bin"
 AR="$BINUTILS/ar"

-DEPS_INCLUDE="$SNAPPY_INCLUDE $ZLIB_INCLUDE $BZIP_INCLUDE $LZ4_INCLUDE $ZSTD_INCLUDE $GFLAGS_INCLUDE $NUMA_INCLUDE $TBB_INCLUDE"
+DEPS_INCLUDE="$SNAPPY_INCLUDE $ZLIB_INCLUDE $BZIP_INCLUDE $LZ4_INCLUDE $ZSTD_INCLUDE $GFLAGS_INCLUDE $NUMA_INCLUDE $TBB_INCLUDE $LIBURING_INCLUDE"

 STDLIBS="-L $GCC_BASE/lib64"

@@ -134,10 +144,10 @@ else
 fi

 CFLAGS+=" $DEPS_INCLUDE"
-CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE -DROCKSDB_RANGESYNC_PRESENT -DROCKSDB_SCHED_GETCPU_PRESENT -DROCKSDB_SUPPORT_THREAD_LOCAL -DHAVE_SSE42"
+CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE -DROCKSDB_RANGESYNC_PRESENT -DROCKSDB_SCHED_GETCPU_PRESENT -DROCKSDB_SUPPORT_THREAD_LOCAL -DHAVE_SSE42 -DROCKSDB_IOURING_PRESENT"
 CXXFLAGS+=" $CFLAGS"

-EXEC_LDFLAGS=" $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $NUMA_LIB $TBB_LIBS"
+EXEC_LDFLAGS=" $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $NUMA_LIB $TBB_LIBS $LIBURING_LIBS"
 EXEC_LDFLAGS+=" -B$BINUTILS/gold"
 EXEC_LDFLAGS+=" -Wl,--dynamic-linker,/usr/local/fbcode/platform007/lib/ld.so"
 EXEC_LDFLAGS+=" $LIBUNWIND"
@@ -147,7 +157,7 @@ EXEC_LDFLAGS+=" -ldl"

 PLATFORM_LDFLAGS="$LIBGCC_LIBS $GLIBC_LIBS $STDLIBS -lgcc -lstdc++"

-EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $TBB_LIBS"
+EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $TBB_LIBS $LIBURING_LIBS"

 VALGRIND_VER="$VALGRIND_BASE/bin/"

@@ -155,4 +165,6 @@ VALGRIND_VER="$VALGRIND_BASE/bin/"
 LUA_PATH=
 LUA_LIB=

+USE_FOLLY_DISTRIBUTED_MUTEX=1
+
 export CC CXX AR CFLAGS CXXFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED VALGRIND_VER JEMALLOC_LIB JEMALLOC_INCLUDE CLANG_ANALYZER CLANG_SCAN_BUILD LUA_PATH LUA_LIB
@@ -13,9 +13,14 @@ then
  echo "You didn't have clang-format-diff.py and/or clang-format available in your computer!"
  echo "You can download clang-format-diff.py by running: "
  echo "    curl --location http://goo.gl/iUW1u2 -o ${CLANG_FORMAT_DIFF}"
-  echo "You can download clang-format by running: "
+  echo "You can download clang-format by running:"
  echo "    brew install clang-format"
+  echo "  Or"
+  echo "    apt install clang-format"
+  echo "  This might work too:"
+  echo "    yum install git-clang-format"
  echo "Then, move both files (i.e. ${CLANG_FORMAT_DIFF} and clang-format) to some directory within PATH=${PATH}"
+  echo "and make sure ${CLANG_FORMAT_DIFF} is executable."
  exit 128
 fi

@@ -54,15 +59,25 @@ fi
 set -e

 uncommitted_code=`git diff HEAD`
-LAST_MASTER=`git merge-base master HEAD`

 # If there's no uncommitted changes, we assume user are doing post-commit
-# format check, in which case we'll check the modified lines since last commit
-# from master. Otherwise, we'll check format of the uncommitted code only.
+# format check, in which case we'll try to check the modified lines vs. the
+# facebook/rocksdb.git master branch. Otherwise, we'll check format of the
+# uncommitted code only.
 if [ -z "$uncommitted_code" ]
 then
-  # Check the format of last commit
-  diffs=$(git diff -U0 $LAST_MASTER^ | $CLANG_FORMAT_DIFF -p 1)
+  # Attempt to get name of facebook/rocksdb.git remote.
+  [ "$FORMAT_REMOTE" ] || FORMAT_REMOTE="$(git remote -v | grep 'facebook/rocksdb.git' | head -n 1 | cut -f 1)"
+  # Fall back on 'origin' if that fails
+  [ "$FORMAT_REMOTE" ] || FORMAT_REMOTE=origin
+  # Use master branch from that remote
+  [ "$FORMAT_UPSTREAM" ] || FORMAT_UPSTREAM="$FORMAT_REMOTE/master"
+  # Get the common ancestor with that remote branch. Everything after that
+  # common ancestor would be considered the contents of a pull request, so
+  # should be relevant for formatting fixes.
+  FORMAT_UPSTREAM_MERGE_BASE="$(git merge-base "$FORMAT_UPSTREAM" HEAD)"
+  # Get the differences
+  diffs=$(git diff -U0 "$FORMAT_UPSTREAM_MERGE_BASE" | $CLANG_FORMAT_DIFF -p 1)
 else
  # Check the format of uncommitted lines,
  diffs=$(git diff -U0 HEAD | $CLANG_FORMAT_DIFF -p 1)
@@ -76,12 +91,12 @@ fi

 # Highlight the insertion/deletion from the clang-format-diff.py's output
 COLOR_END="\033[0m"
-COLOR_RED="\033[0;31m" 
-COLOR_GREEN="\033[0;32m" 
+COLOR_RED="\033[0;31m"
+COLOR_GREEN="\033[0;32m"

 echo -e "Detect lines that doesn't follow the format rules:\r"
 # Add the color to the diff. lines added will be green; lines removed will be red.
-echo "$diffs" | 
+echo "$diffs" |
  sed -e "s/\(^-.*$\)/`echo -e \"$COLOR_RED\1$COLOR_END\"`/" |
  sed -e "s/\(^+.*$\)/`echo -e \"$COLOR_GREEN\1$COLOR_END\"`/"

@@ -104,7 +119,7 @@ fi
 # Do in-place format adjustment.
 if [ -z "$uncommitted_code" ]
 then
-  git diff -U0 $LAST_MASTER^ | $CLANG_FORMAT_DIFF -i -p 1
+  git diff -U0 "$FORMAT_UPSTREAM_MERGE_BASE" | $CLANG_FORMAT_DIFF -i -p 1
 else
  git diff -U0 HEAD^ | $CLANG_FORMAT_DIFF -i -p 1
 fi
@@ -1,4 +1,4 @@
-#!/usr/local/fbcode/gcc-4.9-glibc-2.20-fb/bin/python2.7
+#!/usr/bin/env python2.7
 # Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.

 from __future__ import absolute_import
@@ -450,6 +450,36 @@ STRESS_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS="[
    }
 ]"

+#
+# RocksDB stress/crash test with txn
+#
+STRESS_CRASH_TEST_WITH_TXN_COMMANDS="[
+    {
+        'name':'Rocksdb Stress and Crash Test with txn',
+        'oncall':'$ONCALL',
+        'executeLocal': 'true',
+        'timeout': 86400,
+        'steps': [
+            $CLEANUP_ENV,
+            {
+                'name':'Build and run RocksDB debug stress tests',
+                'shell':'$SHM $DEBUG $NON_TSAN_CRASH make J=1 db_stress || $CONTRUN_NAME=db_stress $TASK_CREATION_TOOL',
+                'user':'root',
+                $PARSER
+            },
+            {
+                'name':'Build and run RocksDB debug crash tests with txn',
+                'timeout': 86400,
+                'shell':'$SHM $DEBUG $NON_TSAN_CRASH make J=1 crash_test_with_txn || $CONTRUN_NAME=crash_test_with_txn $TASK_CREATION_TOOL',
+                'user':'root',
+                $PARSER
+            },
+            $UPLOAD_DB_DIR,
+        ],
+        $REPORT
+    }
+]"
+
 # RocksDB write stress test.
 # We run on disk device on purpose (i.e. no $SHM)
 # because we want to add some randomness to fsync commands
@@ -541,6 +571,30 @@ ASAN_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS="[
    }
 ]"

+#
+# RocksDB crash testing with txn under address sanitizer
+#
+ASAN_CRASH_TEST_WITH_TXN_COMMANDS="[
+    {
+        'name':'Rocksdb crash test with txn under ASAN',
+        'oncall':'$ONCALL',
+        'executeLocal': 'true',
+        'timeout': 86400,
+        'steps': [
+            $CLEANUP_ENV,
+            {
+                'name':'Build and run RocksDB debug asan_crash_test_with_txn',
+                'timeout': 86400,
+                'shell':'$SHM $DEBUG $NON_TSAN_CRASH make J=1 asan_crash_test_with_txn || $CONTRUN_NAME=asan_crash_test_with_txn $TASK_CREATION_TOOL',
+                'user':'root',
+                $PARSER
+            },
+            $UPLOAD_DB_DIR,
+        ],
+        $REPORT
+    }
+]"
+
 #
 # RocksDB test under undefined behavior sanitizer
 #
@@ -553,7 +607,7 @@ UBSAN_TEST_COMMANDS="[
            $CLEANUP_ENV,
            {
                'name':'Test RocksDB debug under UBSAN',
-                'shell':'set -o pipefail && $SHM $UBSAN $DEBUG make $PARALLELISM ubsan_check || $CONTRUN_NAME=ubsan_check $TASK_CREATION_TOOL',
+                'shell':'set -o pipefail && $SHM $UBSAN $CLANG $DEBUG make $PARALLELISM ubsan_check || $CONTRUN_NAME=ubsan_check $TASK_CREATION_TOOL',
                'user':'root',
                $PARSER
            }
@@ -576,7 +630,7 @@ UBSAN_CRASH_TEST_COMMANDS="[
            {
                'name':'Build and run RocksDB debug ubsan_crash_test',
                'timeout': 86400,
-                'shell':'$SHM $DEBUG $NON_TSAN_CRASH make J=1 ubsan_crash_test || $CONTRUN_NAME=ubsan_crash_test $TASK_CREATION_TOOL',
+                'shell':'$SHM $DEBUG $NON_TSAN_CRASH $CLANG make J=1 ubsan_crash_test || $CONTRUN_NAME=ubsan_crash_test $TASK_CREATION_TOOL',
                'user':'root',
                $PARSER
            },
@@ -599,7 +653,31 @@ UBSAN_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS="[
            {
                'name':'Build and run RocksDB debug ubsan_crash_test_with_atomic_flush',
                'timeout': 86400,
-                'shell':'$SHM $DEBUG $NON_TSAN_CRASH make J=1 ubsan_crash_test_with_atomic_flush || $CONTRUN_NAME=ubsan_crash_test_with_atomic_flush $TASK_CREATION_TOOL',
+                'shell':'$SHM $DEBUG $NON_TSAN_CRASH $CLANG make J=1 ubsan_crash_test_with_atomic_flush || $CONTRUN_NAME=ubsan_crash_test_with_atomic_flush $TASK_CREATION_TOOL',
+                'user':'root',
+                $PARSER
+            },
+            $UPLOAD_DB_DIR,
+        ],
+        $REPORT
+    }
+]"
+
+#
+# RocksDB crash testing with txn under undefined behavior sanitizer
+#
+UBSAN_CRASH_TEST_WITH_TXN_COMMANDS="[
+    {
+        'name':'Rocksdb crash test with txn under UBSAN',
+        'oncall':'$ONCALL',
+        'executeLocal': 'true',
+        'timeout': 86400,
+        'steps': [
+            $CLEANUP_ENV,
+            {
+                'name':'Build and run RocksDB debug ubsan_crash_test_with_txn',
+                'timeout': 86400,
+                'shell':'$SHM $DEBUG $NON_TSAN_CRASH $CLANG make J=1 ubsan_crash_test_with_txn || $CONTRUN_NAME=ubsan_crash_test_with_txn $TASK_CREATION_TOOL',
                'user':'root',
                $PARSER
            },
@@ -702,6 +780,30 @@ TSAN_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS="[
    }
 ]"

+#
+# RocksDB crash test with txn under TSAN
+#
+TSAN_CRASH_TEST_WITH_TXN_COMMANDS="[
+    {
+        'name':'Rocksdb Crash Test with txn under TSAN',
+        'oncall':'$ONCALL',
+        'executeLocal': 'true',
+        'timeout': 86400,
+        'steps': [
+            $CLEANUP_ENV,
+            {
+                'name':'Compile and run',
+                'timeout': 86400,
+                'shell':'set -o pipefail && $SHM $DEBUG $TSAN $TSAN_CRASH CRASH_TEST_KILL_ODD=1887 make J=1 crash_test_with_txn || $CONTRUN_NAME=tsan_crash_test_with_txn $TASK_CREATION_TOOL',
+                'user':'root',
+                $PARSER
+            },
+            $UPLOAD_DB_DIR,
+        ],
+        $REPORT
+    }
+]"
+
 #
 # RocksDB format compatible
 #
@@ -889,6 +991,9 @@ case $1 in
  stress_crash_with_atomic_flush)
    echo $STRESS_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS
    ;;
+  stress_crash_with_txn)
+    echo $STRESS_CRASH_TEST_WITH_TXN_COMMANDS
+    ;;
  write_stress)
    echo $WRITE_STRESS_COMMANDS
    ;;
@@ -901,6 +1006,9 @@ case $1 in
  asan_crash_with_atomic_flush)
    echo $ASAN_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS
    ;;
+  asan_crash_with_txn)
+    echo $ASAN_CRASH_TEST_WITH_TXN_COMMANDS
+    ;;
  ubsan)
    echo $UBSAN_TEST_COMMANDS
    ;;
@@ -910,6 +1018,9 @@ case $1 in
  ubsan_crash_with_atomic_flush)
    echo $UBSAN_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS
    ;;
+  ubsan_crash_with_txn)
+    echo $UBSAN_CRASH_TEST_WITH_TXN_COMMANDS
+    ;;
  valgrind)
    echo $VALGRIND_TEST_COMMANDS
    ;;
@@ -922,6 +1033,9 @@ case $1 in
  tsan_crash_with_atomic_flush)
    echo $TSAN_CRASH_TEST_WITH_ATOMIC_FLUSH_COMMANDS
    ;;
+  tsan_crash_with_txn)
+    echo $TSAN_CRASH_TEST_WITH_TXN_COMMANDS
+    ;;
  format_compatible)
    echo $FORMAT_COMPATIBLE_COMMANDS
    ;;
@@ -6,6 +6,12 @@
 BASEDIR=$(dirname $0)
 OUTPUT=""

+function log_header()
+{
+  echo "# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved." >> "$OUTPUT"
+}
+
+
 function log_variable()
 {
  echo "$1=${!1}" >> "$OUTPUT"
@@ -69,6 +75,7 @@ echo "Writing dependencies to $OUTPUT"
 GCC_BASE=`readlink -f $TP2_LATEST/gcc/7.x/centos7-native/*/`
 CLANG_BASE=`readlink -f $TP2_LATEST/llvm-fb/stable/centos7-native/*/`

+log_header
 log_variable GCC_BASE
 log_variable CLANG_BASE

@@ -85,6 +92,7 @@ get_lib_base jemalloc   LATEST  platform007
 get_lib_base numa       LATEST  platform007
 get_lib_base libunwind  LATEST  platform007
 get_lib_base tbb        LATEST  platform007
+get_lib_base liburing   LATEST  platform007

 get_lib_base kernel-headers fb platform007
 get_lib_base binutils   LATEST centos7-native
@@ -108,6 +116,7 @@ echo "Writing dependencies to $OUTPUT"
 GCC_BASE=`readlink -f $TP2_LATEST/gcc/5.x/centos7-native/*/`
 CLANG_BASE=`readlink -f $TP2_LATEST/llvm-fb/stable/centos7-native/*/`

+log_header
 log_variable GCC_BASE
 log_variable CLANG_BASE

@@ -147,6 +156,7 @@ echo "Writing 4.8.1 dependencies to $OUTPUT"
 GCC_BASE=`readlink -f $TP2_LATEST/gcc/4.8.1/centos6-native/*/`
 CLANG_BASE=`readlink -f $TP2_LATEST/llvm-fb/stable/centos6-native/*/`

+log_header
 log_variable GCC_BASE
 log_variable CLANG_BASE

@@ -11,9 +11,9 @@ int main() {
 }
 #else

-#include <cinttypes>
-#include <sys/types.h>
 #include <stdio.h>
+#include <sys/types.h>
+#include <cinttypes>

 #include "port/port.h"
 #include "rocksdb/cache.h"
@@ -86,14 +86,22 @@ class CacheTest : public testing::TestWithParam<std::string> {
    return nullptr;
  }

-  std::shared_ptr<Cache> NewCache(size_t capacity, int num_shard_bits,
-                                  bool strict_capacity_limit) {
+  std::shared_ptr<Cache> NewCache(
+      size_t capacity, int num_shard_bits, bool strict_capacity_limit,
+      CacheMetadataChargePolicy charge_policy = kDontChargeCacheMetadata) {
    auto type = GetParam();
    if (type == kLRU) {
-      return NewLRUCache(capacity, num_shard_bits, strict_capacity_limit, 0.0);
+      LRUCacheOptions co;
+      co.capacity = capacity;
+      co.num_shard_bits = num_shard_bits;
+      co.strict_capacity_limit = strict_capacity_limit;
+      co.high_pri_pool_ratio = 0;
+      co.metadata_charge_policy = charge_policy;
+      return NewLRUCache(co);
    }
    if (type == kClock) {
-      return NewClockCache(capacity, num_shard_bits, strict_capacity_limit);
+      return NewClockCache(capacity, num_shard_bits, strict_capacity_limit,
+                           charge_policy);
    }
    return nullptr;
  }
@@ -143,10 +151,15 @@ class CacheTest : public testing::TestWithParam<std::string> {
 };
 CacheTest* CacheTest::current_;

+class LRUCacheTest : public CacheTest {};
+
 TEST_P(CacheTest, UsageTest) {
  // cache is std::shared_ptr and will be automatically cleaned up.
  const uint64_t kCapacity = 100000;
-  auto cache = NewCache(kCapacity, 8, false);
+  auto cache = NewCache(kCapacity, 8, false, kDontChargeCacheMetadata);
+  auto precise_cache = NewCache(kCapacity, 0, false, kFullChargeCacheMetadata);
+  ASSERT_EQ(0, cache->GetUsage());
+  ASSERT_EQ(0, precise_cache->GetUsage());

  size_t usage = 0;
  char value[10] = "abcdef";
@@ -155,31 +168,45 @@ TEST_P(CacheTest, UsageTest) {
    std::string key(i, 'a');
    auto kv_size = key.size() + 5;
    cache->Insert(key, reinterpret_cast<void*>(value), kv_size, dumbDeleter);
+    precise_cache->Insert(key, reinterpret_cast<void*>(value), kv_size,
+                          dumbDeleter);
    usage += kv_size;
    ASSERT_EQ(usage, cache->GetUsage());
+    ASSERT_LT(usage, precise_cache->GetUsage());
  }

+  cache->EraseUnRefEntries();
+  precise_cache->EraseUnRefEntries();
+  ASSERT_EQ(0, cache->GetUsage());
+  ASSERT_EQ(0, precise_cache->GetUsage());
+
  // make sure the cache will be overloaded
  for (uint64_t i = 1; i < kCapacity; ++i) {
    auto key = ToString(i);
    cache->Insert(key, reinterpret_cast<void*>(value), key.size() + 5,
                  dumbDeleter);
+    precise_cache->Insert(key, reinterpret_cast<void*>(value), key.size() + 5,
+                          dumbDeleter);
  }

  // the usage should be close to the capacity
  ASSERT_GT(kCapacity, cache->GetUsage());
+  ASSERT_GT(kCapacity, precise_cache->GetUsage());
  ASSERT_LT(kCapacity * 0.95, cache->GetUsage());
+  ASSERT_LT(kCapacity * 0.95, precise_cache->GetUsage());
 }

 TEST_P(CacheTest, PinnedUsageTest) {
  // cache is std::shared_ptr and will be automatically cleaned up.
-  const uint64_t kCapacity = 100000;
-  auto cache = NewCache(kCapacity, 8, false);
+  const uint64_t kCapacity = 200000;
+  auto cache = NewCache(kCapacity, 8, false, kDontChargeCacheMetadata);
+  auto precise_cache = NewCache(kCapacity, 8, false, kFullChargeCacheMetadata);

  size_t pinned_usage = 0;
  char value[10] = "abcdef";

  std::forward_list<Cache::Handle*> unreleased_handles;
+  std::forward_list<Cache::Handle*> unreleased_handles_in_precise_cache;

  // Add entries. Unpin some of them after insertion. Then, pin some of them
  // again. Check GetPinnedUsage().
@@ -187,40 +214,72 @@ TEST_P(CacheTest, PinnedUsageTest) {
    std::string key(i, 'a');
    auto kv_size = key.size() + 5;
    Cache::Handle* handle;
+    Cache::Handle* handle_in_precise_cache;
    cache->Insert(key, reinterpret_cast<void*>(value), kv_size, dumbDeleter,
                  &handle);
+    assert(handle);
+    precise_cache->Insert(key, reinterpret_cast<void*>(value), kv_size,
+                          dumbDeleter, &handle_in_precise_cache);
+    assert(handle_in_precise_cache);
    pinned_usage += kv_size;
    ASSERT_EQ(pinned_usage, cache->GetPinnedUsage());
+    ASSERT_LT(pinned_usage, precise_cache->GetPinnedUsage());
    if (i % 2 == 0) {
      cache->Release(handle);
+      precise_cache->Release(handle_in_precise_cache);
      pinned_usage -= kv_size;
      ASSERT_EQ(pinned_usage, cache->GetPinnedUsage());
+      ASSERT_LT(pinned_usage, precise_cache->GetPinnedUsage());
    } else {
      unreleased_handles.push_front(handle);
+      unreleased_handles_in_precise_cache.push_front(handle_in_precise_cache);
    }
    if (i % 3 == 0) {
      unreleased_handles.push_front(cache->Lookup(key));
+      auto x = precise_cache->Lookup(key);
+      assert(x);
+      unreleased_handles_in_precise_cache.push_front(x);
      // If i % 2 == 0, then the entry was unpinned before Lookup, so pinned
      // usage increased
      if (i % 2 == 0) {
        pinned_usage += kv_size;
      }
      ASSERT_EQ(pinned_usage, cache->GetPinnedUsage());
+      ASSERT_LT(pinned_usage, precise_cache->GetPinnedUsage());
    }
  }
+  auto precise_cache_pinned_usage = precise_cache->GetPinnedUsage();
+  ASSERT_LT(pinned_usage, precise_cache_pinned_usage);

  // check that overloading the cache does not change the pinned usage
  for (uint64_t i = 1; i < 2 * kCapacity; ++i) {
    auto key = ToString(i);
    cache->Insert(key, reinterpret_cast<void*>(value), key.size() + 5,
                  dumbDeleter);
+    precise_cache->Insert(key, reinterpret_cast<void*>(value), key.size() + 5,
+                          dumbDeleter);
  }
  ASSERT_EQ(pinned_usage, cache->GetPinnedUsage());
+  ASSERT_EQ(precise_cache_pinned_usage, precise_cache->GetPinnedUsage());
+
+  cache->EraseUnRefEntries();
+  precise_cache->EraseUnRefEntries();
+  ASSERT_EQ(pinned_usage, cache->GetPinnedUsage());
+  ASSERT_EQ(precise_cache_pinned_usage, precise_cache->GetPinnedUsage());

  // release handles for pinned entries to prevent memory leaks
  for (auto handle : unreleased_handles) {
    cache->Release(handle);
  }
+  for (auto handle : unreleased_handles_in_precise_cache) {
+    precise_cache->Release(handle);
+  }
+  ASSERT_EQ(0, cache->GetPinnedUsage());
+  ASSERT_EQ(0, precise_cache->GetPinnedUsage());
+  cache->EraseUnRefEntries();
+  precise_cache->EraseUnRefEntries();
+  ASSERT_EQ(0, cache->GetUsage());
+  ASSERT_EQ(0, precise_cache->GetUsage());
 }

 TEST_P(CacheTest, HitAndMiss) {
@@ -306,7 +365,7 @@ TEST_P(CacheTest, EvictionPolicy) {
  Insert(200, 201);

  // Frequently used entry must be kept around
-  for (int i = 0; i < kCacheSize + 200; i++) {
+  for (int i = 0; i < kCacheSize * 2; i++) {
    Insert(1000+i, 2000+i);
    ASSERT_EQ(101, Lookup(100));
  }
@@ -359,7 +418,7 @@ TEST_P(CacheTest, EvictionPolicyRef) {
  Insert(303, 104);

  // Insert entries much more than Cache capacity
-  for (int i = 0; i < kCacheSize + 200; i++) {
+  for (int i = 0; i < kCacheSize * 2; i++) {
    Insert(1000 + i, 2000 + i);
  }

@@ -550,10 +609,10 @@ TEST_P(CacheTest, SetCapacity) {
  }
 }

-TEST_P(CacheTest, SetStrictCapacityLimit) {
+TEST_P(LRUCacheTest, SetStrictCapacityLimit) {
  // test1: set the flag to false. Insert more keys than capacity. See if they
  // all go through.
-  std::shared_ptr<Cache> cache = NewLRUCache(5, 0, false);
+  std::shared_ptr<Cache> cache = NewCache(5, 0, false);
  std::vector<Cache::Handle*> handles(10);
  Status s;
  for (size_t i = 0; i < 10; i++) {
@@ -579,7 +638,7 @@ TEST_P(CacheTest, SetStrictCapacityLimit) {
  }

  // test3: init with flag being true.
-  std::shared_ptr<Cache> cache2 = NewLRUCache(5, 0, true);
+  std::shared_ptr<Cache> cache2 = NewCache(5, 0, true);
  for (size_t i = 0; i < 5; i++) {
    std::string key = ToString(i + 1);
    s = cache2->Insert(key, new Value(i + 1), 1, &deleter, &handles[i]);
@@ -697,13 +756,14 @@ TEST_P(CacheTest, GetCharge) {
 }

 #ifdef SUPPORT_CLOCK_CACHE
-std::shared_ptr<Cache> (*new_clock_cache_func)(size_t, int,
-                                               bool) = NewClockCache;
+std::shared_ptr<Cache> (*new_clock_cache_func)(
+    size_t, int, bool, CacheMetadataChargePolicy) = NewClockCache;
 INSTANTIATE_TEST_CASE_P(CacheTestInstance, CacheTest,
                        testing::Values(kLRU, kClock));
 #else
 INSTANTIATE_TEST_CASE_P(CacheTestInstance, CacheTest, testing::Values(kLRU));
 #endif  // SUPPORT_CLOCK_CACHE
+INSTANTIATE_TEST_CASE_P(CacheTestInstance, LRUCacheTest, testing::Values(kLRU));

 }  // namespace rocksdb

@@ -13,8 +13,9 @@

 namespace rocksdb {

-std::shared_ptr<Cache> NewClockCache(size_t /*capacity*/, int /*num_shard_bits*/,
-                                     bool /*strict_capacity_limit*/) {
+std::shared_ptr<Cache> NewClockCache(
+    size_t /*capacity*/, int /*num_shard_bits*/, bool /*strict_capacity_limit*/,
+    CacheMetadataChargePolicy /*metadata_charge_policy*/) {
  // Clock cache not supported.
  return nullptr;
 }
@@ -35,6 +36,7 @@ std::shared_ptr<Cache> NewClockCache(size_t /*capacity*/, int /*num_shard_bits*/
 #include "tbb/concurrent_hash_map.h"

 #include "cache/sharded_cache.h"
+#include "port/malloc.h"
 #include "port/port.h"
 #include "util/autovector.h"
 #include "util/mutexlock.h"
@@ -202,6 +204,27 @@ struct CacheHandle {
    deleter = a.deleter;
    return *this;
  }
+
+  inline static size_t CalcTotalCharge(
+      Slice key, size_t charge,
+      CacheMetadataChargePolicy metadata_charge_policy) {
+    size_t meta_charge = 0;
+    if (metadata_charge_policy == kFullChargeCacheMetadata) {
+      meta_charge += sizeof(CacheHandle);
+#ifdef ROCKSDB_MALLOC_USABLE_SIZE
+      meta_charge +=
+          malloc_usable_size(static_cast<void*>(const_cast<char*>(key.data())));
+#else
+      meta_charge += key.size();
+#endif
+    }
+    return charge + meta_charge;
+  }
+
+  inline size_t CalcTotalCharge(
+      CacheMetadataChargePolicy metadata_charge_policy) {
+    return CalcTotalCharge(key, charge, metadata_charge_policy);
+  }
 };

 // Key of hash map. We store hash value with the key for convenience.
@@ -404,11 +427,12 @@ void ClockCacheShard::RecycleHandle(CacheHandle* handle,
  assert(!InCache(handle->flags) && CountRefs(handle->flags) == 0);
  context->to_delete_key.push_back(handle->key.data());
  context->to_delete_value.emplace_back(*handle);
+  size_t total_charge = handle->CalcTotalCharge(metadata_charge_policy_);
  handle->key.clear();
  handle->value = nullptr;
  handle->deleter = nullptr;
  recycle_.push_back(handle);
-  usage_.fetch_sub(handle->charge, std::memory_order_relaxed);
+  usage_.fetch_sub(total_charge, std::memory_order_relaxed);
 }

 void ClockCacheShard::Cleanup(const CleanupContext& context) {
@@ -434,7 +458,8 @@ bool ClockCacheShard::Ref(Cache::Handle* h) {
                                            std::memory_order_relaxed)) {
      if (CountRefs(flags) == 0) {
        // No reference count before the operation.
-        pinned_usage_.fetch_add(handle->charge, std::memory_order_relaxed);
+        size_t total_charge = handle->CalcTotalCharge(metadata_charge_policy_);
+        pinned_usage_.fetch_add(total_charge, std::memory_order_relaxed);
      }
      return true;
    }
@@ -454,7 +479,8 @@ bool ClockCacheShard::Unref(CacheHandle* handle, bool set_usage,
  assert(CountRefs(flags) > 0);
  if (CountRefs(flags) == 1) {
    // this is the last reference.
-    pinned_usage_.fetch_sub(handle->charge, std::memory_order_relaxed);
+    size_t total_charge = handle->CalcTotalCharge(metadata_charge_policy_);
+    pinned_usage_.fetch_sub(total_charge, std::memory_order_relaxed);
    // Cleanup if it is the last reference.
    if (!InCache(flags)) {
      MutexLock l(&mutex_);
@@ -539,8 +565,10 @@ CacheHandle* ClockCacheShard::Insert(
    const Slice& key, uint32_t hash, void* value, size_t charge,
    void (*deleter)(const Slice& key, void* value), bool hold_reference,
    CleanupContext* context) {
+  size_t total_charge =
+      CacheHandle::CalcTotalCharge(key, charge, metadata_charge_policy_);
  MutexLock l(&mutex_);
-  bool success = EvictFromCache(charge, context);
+  bool success = EvictFromCache(total_charge, context);
  bool strict = strict_capacity_limit_.load(std::memory_order_relaxed);
  if (!success && (strict || !hold_reference)) {
    context->to_delete_key.push_back(key.data());
@@ -575,9 +603,9 @@ CacheHandle* ClockCacheShard::Insert(
  }
  table_.insert(HashTable::value_type(CacheKey(key, hash), handle));
  if (hold_reference) {
-    pinned_usage_.fetch_add(charge, std::memory_order_relaxed);
+    pinned_usage_.fetch_add(total_charge, std::memory_order_relaxed);
  }
-  usage_.fetch_add(charge, std::memory_order_relaxed);
+  usage_.fetch_add(total_charge, std::memory_order_relaxed);
  return handle;
 }

@@ -674,10 +702,14 @@ void ClockCacheShard::EraseUnRefEntries() {

 class ClockCache final : public ShardedCache {
 public:
-  ClockCache(size_t capacity, int num_shard_bits, bool strict_capacity_limit)
+  ClockCache(size_t capacity, int num_shard_bits, bool strict_capacity_limit,
+             CacheMetadataChargePolicy metadata_charge_policy)
      : ShardedCache(capacity, num_shard_bits, strict_capacity_limit) {
    int num_shards = 1 << num_shard_bits;
    shards_ = new ClockCacheShard[num_shards];
+    for (int i = 0; i < num_shards; i++) {
+      shards_[i].set_metadata_charge_policy(metadata_charge_policy);
+    }
    SetCapacity(capacity);
    SetStrictCapacityLimit(strict_capacity_limit);
  }
@@ -714,13 +746,14 @@ class ClockCache final : public ShardedCache {

 }  // end anonymous namespace

-std::shared_ptr<Cache> NewClockCache(size_t capacity, int num_shard_bits,
-                                     bool strict_capacity_limit) {
+std::shared_ptr<Cache> NewClockCache(
+    size_t capacity, int num_shard_bits, bool strict_capacity_limit,
+    CacheMetadataChargePolicy metadata_charge_policy) {
  if (num_shard_bits < 0) {
    num_shard_bits = GetDefaultCacheShardBits(capacity);
  }
-  return std::make_shared<ClockCache>(capacity, num_shard_bits,
-                                      strict_capacity_limit);
+  return std::make_shared<ClockCache>(
+      capacity, num_shard_bits, strict_capacity_limit, metadata_charge_policy);
 }

 }  // namespace rocksdb
@@ -97,7 +97,8 @@ void LRUHandleTable::Resize() {

 LRUCacheShard::LRUCacheShard(size_t capacity, bool strict_capacity_limit,
                             double high_pri_pool_ratio,
-                             bool use_adaptive_mutex)
+                             bool use_adaptive_mutex,
+                             CacheMetadataChargePolicy metadata_charge_policy)
    : capacity_(0),
      high_pri_pool_usage_(0),
      strict_capacity_limit_(strict_capacity_limit),
@@ -106,6 +107,7 @@ LRUCacheShard::LRUCacheShard(size_t capacity, bool strict_capacity_limit,
      usage_(0),
      lru_usage_(0),
      mutex_(use_adaptive_mutex) {
+  set_metadata_charge_policy(metadata_charge_policy);
  // Make empty circular linked list
  lru_.next = &lru_;
  lru_.prev = &lru_;
@@ -124,7 +126,9 @@ void LRUCacheShard::EraseUnRefEntries() {
      LRU_Remove(old);
      table_.Remove(old->key(), old->hash);
      old->SetInCache(false);
-      usage_ -= old->charge;
+      size_t total_charge = old->CalcTotalCharge(metadata_charge_policy_);
+      assert(usage_ >= total_charge);
+      usage_ -= total_charge;
      last_reference_list.push_back(old);
    }
  }
@@ -180,16 +184,19 @@ void LRUCacheShard::LRU_Remove(LRUHandle* e) {
  e->next->prev = e->prev;
  e->prev->next = e->next;
  e->prev = e->next = nullptr;
-  lru_usage_ -= e->charge;
+  size_t total_charge = e->CalcTotalCharge(metadata_charge_policy_);
+  assert(lru_usage_ >= total_charge);
+  lru_usage_ -= total_charge;
  if (e->InHighPriPool()) {
-    assert(high_pri_pool_usage_ >= e->charge);
-    high_pri_pool_usage_ -= e->charge;
+    assert(high_pri_pool_usage_ >= total_charge);
+    high_pri_pool_usage_ -= total_charge;
  }
 }

 void LRUCacheShard::LRU_Insert(LRUHandle* e) {
  assert(e->next == nullptr);
  assert(e->prev == nullptr);
+  size_t total_charge = e->CalcTotalCharge(metadata_charge_policy_);
  if (high_pri_pool_ratio_ > 0 && (e->IsHighPri() || e->HasHit())) {
    // Inset "e" to head of LRU list.
    e->next = &lru_;
@@ -197,7 +204,7 @@ void LRUCacheShard::LRU_Insert(LRUHandle* e) {
    e->prev->next = e;
    e->next->prev = e;
    e->SetInHighPriPool(true);
-    high_pri_pool_usage_ += e->charge;
+    high_pri_pool_usage_ += total_charge;
    MaintainPoolSize();
  } else {
    // Insert "e" to the head of low-pri pool. Note that when
@@ -209,7 +216,7 @@ void LRUCacheShard::LRU_Insert(LRUHandle* e) {
    e->SetInHighPriPool(false);
    lru_low_pri_ = e;
  }
-  lru_usage_ += e->charge;
+  lru_usage_ += total_charge;
 }

 void LRUCacheShard::MaintainPoolSize() {
@@ -218,7 +225,10 @@ void LRUCacheShard::MaintainPoolSize() {
    lru_low_pri_ = lru_low_pri_->next;
    assert(lru_low_pri_ != &lru_);
    lru_low_pri_->SetInHighPriPool(false);
-    high_pri_pool_usage_ -= lru_low_pri_->charge;
+    size_t total_charge =
+        lru_low_pri_->CalcTotalCharge(metadata_charge_policy_);
+    assert(high_pri_pool_usage_ >= total_charge);
+    high_pri_pool_usage_ -= total_charge;
  }
 }

@@ -231,7 +241,9 @@ void LRUCacheShard::EvictFromLRU(size_t charge,
    LRU_Remove(old);
    table_.Remove(old->key(), old->hash);
    old->SetInCache(false);
-    usage_ -= old->charge;
+    size_t old_total_charge = old->CalcTotalCharge(metadata_charge_policy_);
+    assert(usage_ >= old_total_charge);
+    usage_ -= old_total_charge;
    deleted->push_back(old);
  }
 }
@@ -311,7 +323,9 @@ bool LRUCacheShard::Release(Cache::Handle* handle, bool force_erase) {
      }
    }
    if (last_reference) {
-      usage_ -= e->charge;
+      size_t total_charge = e->CalcTotalCharge(metadata_charge_policy_);
+      assert(usage_ >= total_charge);
+      usage_ -= total_charge;
    }
  }

@@ -345,15 +359,16 @@ Status LRUCacheShard::Insert(const Slice& key, uint32_t hash, void* value,
  e->SetInCache(true);
  e->SetPriority(priority);
  memcpy(e->key_data, key.data(), key.size());
+  size_t total_charge = e->CalcTotalCharge(metadata_charge_policy_);

  {
    MutexLock l(&mutex_);

    // Free the space following strict LRU policy until enough space
    // is freed or the lru list is empty
-    EvictFromLRU(charge, &last_reference_list);
+    EvictFromLRU(total_charge, &last_reference_list);

-    if ((usage_ + charge) > capacity_ &&
+    if ((usage_ + total_charge) > capacity_ &&
        (strict_capacity_limit_ || handle == nullptr)) {
      if (handle == nullptr) {
        // Don't insert the entry but still return ok, as if the entry inserted
@@ -369,14 +384,17 @@ Status LRUCacheShard::Insert(const Slice& key, uint32_t hash, void* value,
      // Insert into the cache. Note that the cache might get larger than its
      // capacity if not enough space was freed up.
      LRUHandle* old = table_.Insert(e);
-      usage_ += e->charge;
+      usage_ += total_charge;
      if (old != nullptr) {
        assert(old->InCache());
        old->SetInCache(false);
        if (!old->HasRefs()) {
          // old is on LRU because it's in cache and its reference count is 0
          LRU_Remove(old);
-          usage_ -= old->charge;
+          size_t old_total_charge =
+              old->CalcTotalCharge(metadata_charge_policy_);
+          assert(usage_ >= old_total_charge);
+          usage_ -= old_total_charge;
          last_reference_list.push_back(old);
        }
      }
@@ -409,7 +427,9 @@ void LRUCacheShard::Erase(const Slice& key, uint32_t hash) {
      if (!e->HasRefs()) {
        // The entry is in LRU since it's in hash and has no external references
        LRU_Remove(e);
-        usage_ -= e->charge;
+        size_t total_charge = e->CalcTotalCharge(metadata_charge_policy_);
+        assert(usage_ >= total_charge);
+        usage_ -= total_charge;
        last_reference = true;
      }
    }
@@ -447,7 +467,8 @@ std::string LRUCacheShard::GetPrintableOptions() const {
 LRUCache::LRUCache(size_t capacity, int num_shard_bits,
                   bool strict_capacity_limit, double high_pri_pool_ratio,
                   std::shared_ptr<MemoryAllocator> allocator,
-                   bool use_adaptive_mutex)
+                   bool use_adaptive_mutex,
+                   CacheMetadataChargePolicy metadata_charge_policy)
    : ShardedCache(capacity, num_shard_bits, strict_capacity_limit,
                   std::move(allocator)) {
  num_shards_ = 1 << num_shard_bits;
@@ -457,7 +478,7 @@ LRUCache::LRUCache(size_t capacity, int num_shard_bits,
  for (int i = 0; i < num_shards_; i++) {
    new (&shards_[i])
        LRUCacheShard(per_shard, strict_capacity_limit, high_pri_pool_ratio,
-            use_adaptive_mutex);
+                      use_adaptive_mutex, metadata_charge_policy);
  }
 }

@@ -526,15 +547,15 @@ std::shared_ptr<Cache> NewLRUCache(const LRUCacheOptions& cache_opts) {
  return NewLRUCache(cache_opts.capacity, cache_opts.num_shard_bits,
                     cache_opts.strict_capacity_limit,
                     cache_opts.high_pri_pool_ratio,
-                     cache_opts.memory_allocator,
-                     cache_opts.use_adaptive_mutex);
+                     cache_opts.memory_allocator, cache_opts.use_adaptive_mutex,
+                     cache_opts.metadata_charge_policy);
 }

 std::shared_ptr<Cache> NewLRUCache(
    size_t capacity, int num_shard_bits, bool strict_capacity_limit,
    double high_pri_pool_ratio,
-    std::shared_ptr<MemoryAllocator> memory_allocator,
-    bool use_adaptive_mutex) {
+    std::shared_ptr<MemoryAllocator> memory_allocator, bool use_adaptive_mutex,
+    CacheMetadataChargePolicy metadata_charge_policy) {
  if (num_shard_bits >= 20) {
    return nullptr;  // the cache cannot be sharded into too many fine pieces
  }
@@ -545,10 +566,9 @@ std::shared_ptr<Cache> NewLRUCache(
  if (num_shard_bits < 0) {
    num_shard_bits = GetDefaultCacheShardBits(capacity);
  }
-  return std::make_shared<LRUCache>(capacity, num_shard_bits,
-                                    strict_capacity_limit, high_pri_pool_ratio,
-                                    std::move(memory_allocator),
-                                    use_adaptive_mutex);
+  return std::make_shared<LRUCache>(
+      capacity, num_shard_bits, strict_capacity_limit, high_pri_pool_ratio,
+      std::move(memory_allocator), use_adaptive_mutex, metadata_charge_policy);
 }

 }  // namespace rocksdb
@@ -12,6 +12,7 @@

 #include "cache/sharded_cache.h"

+#include "port/malloc.h"
 #include "port/port.h"
 #include "util/autovector.h"

@@ -128,6 +129,21 @@ struct LRUHandle {
    }
    delete[] reinterpret_cast<char*>(this);
  }
+
+  // Caclculate the memory usage by metadata
+  inline size_t CalcTotalCharge(
+      CacheMetadataChargePolicy metadata_charge_policy) {
+    size_t meta_charge = 0;
+    if (metadata_charge_policy == kFullChargeCacheMetadata) {
+#ifdef ROCKSDB_MALLOC_USABLE_SIZE
+      meta_charge += malloc_usable_size(static_cast<void*>(this));
+#else
+      // This is the size that is used when a new handle is created
+      meta_charge += sizeof(LRUHandle) - 1 + key_length;
+#endif
+    }
+    return charge + meta_charge;
+  }
 };

 // We provide our own simple hash table since it removes a whole bunch
@@ -176,7 +192,8 @@ class LRUHandleTable {
 class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard {
 public:
  LRUCacheShard(size_t capacity, bool strict_capacity_limit,
-                double high_pri_pool_ratio, bool use_adaptive_mutex);
+                double high_pri_pool_ratio, bool use_adaptive_mutex,
+                CacheMetadataChargePolicy metadata_charge_policy);
  virtual ~LRUCacheShard() override = default;

  // Separate from constructor so caller can easily make an array of LRUCache
@@ -297,7 +314,9 @@ class LRUCache
  LRUCache(size_t capacity, int num_shard_bits, bool strict_capacity_limit,
           double high_pri_pool_ratio,
           std::shared_ptr<MemoryAllocator> memory_allocator = nullptr,
-           bool use_adaptive_mutex = kDefaultToAdaptiveMutex);
+           bool use_adaptive_mutex = kDefaultToAdaptiveMutex,
+           CacheMetadataChargePolicy metadata_charge_policy =
+               kDontChargeCacheMetadata);
  virtual ~LRUCache();
  virtual const char* Name() const override { return "LRUCache"; }
  virtual CacheShard* GetShard(int shard) override;
@@ -31,7 +31,8 @@ class LRUCacheTest : public testing::Test {
    cache_ = reinterpret_cast<LRUCacheShard*>(
        port::cacheline_aligned_alloc(sizeof(LRUCacheShard)));
    new (cache_) LRUCacheShard(capacity, false /*strict_capcity_limit*/,
-                               high_pri_pool_ratio, use_adaptive_mutex);
+                               high_pri_pool_ratio, use_adaptive_mutex,
+                               kDontChargeCacheMetadata);
  }

  void Insert(const std::string& key,
@@ -40,6 +40,13 @@ class CacheShard {
                                      bool thread_safe) = 0;
  virtual void EraseUnRefEntries() = 0;
  virtual std::string GetPrintableOptions() const { return ""; }
+  void set_metadata_charge_policy(
+      CacheMetadataChargePolicy metadata_charge_policy) {
+    metadata_charge_policy_ = metadata_charge_policy;
+  }
+
+ protected:
+  CacheMetadataChargePolicy metadata_charge_policy_ = kDontChargeCacheMetadata;
 };

 // Generic cache interface which shards cache by hash of keys. 2^num_shard_bits
@@ -1,21 +1,29 @@
 # - Find JeMalloc library
 # Find the native JeMalloc includes and library
 #
-# JEMALLOC_INCLUDE_DIR - where to find jemalloc.h, etc.
-# JEMALLOC_LIBRARIES - List of libraries when using jemalloc.
-# JEMALLOC_FOUND - True if jemalloc found.
+# JeMalloc_INCLUDE_DIRS - where to find jemalloc.h, etc.
+# JeMalloc_LIBRARIES - List of libraries when using jemalloc.
+# JeMalloc_FOUND - True if jemalloc found.

-find_path(JEMALLOC_INCLUDE_DIR
+find_path(JeMalloc_INCLUDE_DIRS
  NAMES jemalloc/jemalloc.h
  HINTS ${JEMALLOC_ROOT_DIR}/include)

-find_library(JEMALLOC_LIBRARIES
+find_library(JeMalloc_LIBRARIES
  NAMES jemalloc
  HINTS ${JEMALLOC_ROOT_DIR}/lib)

 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(jemalloc DEFAULT_MSG JEMALLOC_LIBRARIES JEMALLOC_INCLUDE_DIR)
+find_package_handle_standard_args(JeMalloc DEFAULT_MSG JeMalloc_LIBRARIES JeMalloc_INCLUDE_DIRS)

 mark_as_advanced(
-  JEMALLOC_LIBRARIES
-  JEMALLOC_INCLUDE_DIR)
+  JeMalloc_LIBRARIES
+  JeMalloc_INCLUDE_DIRS)
+
+if(JeMalloc_FOUND AND NOT (TARGET JeMalloc::JeMalloc))
+  add_library (JeMalloc::JeMalloc UNKNOWN IMPORTED)
+  set_target_properties(JeMalloc::JeMalloc
+    PROPERTIES
+      IMPORTED_LOCATION ${JeMalloc_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${JeMalloc_INCLUDE_DIRS})
+endif()
@@ -1,11 +1,11 @@
 # - Find NUMA
 # Find the NUMA library and includes
 #
-# NUMA_INCLUDE_DIR - where to find numa.h, etc.
+# NUMA_INCLUDE_DIRS - where to find numa.h, etc.
 # NUMA_LIBRARIES - List of libraries when using NUMA.
 # NUMA_FOUND - True if NUMA found.

-find_path(NUMA_INCLUDE_DIR
+find_path(NUMA_INCLUDE_DIRS
  NAMES numa.h numaif.h
  HINTS ${NUMA_ROOT_DIR}/include)

@@ -14,8 +14,16 @@ find_library(NUMA_LIBRARIES
  HINTS ${NUMA_ROOT_DIR}/lib)

 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(NUMA DEFAULT_MSG NUMA_LIBRARIES NUMA_INCLUDE_DIR)
+find_package_handle_standard_args(NUMA DEFAULT_MSG NUMA_LIBRARIES NUMA_INCLUDE_DIRS)

 mark_as_advanced(
  NUMA_LIBRARIES
-  NUMA_INCLUDE_DIR)
+  NUMA_INCLUDE_DIRS)
+
+if(NUMA_FOUND AND NOT (TARGET NUMA::NUMA))
+  add_library (NUMA::NUMA UNKNOWN IMPORTED)
+  set_target_properties(NUMA::NUMA
+    PROPERTIES
+      IMPORTED_LOCATION ${NUMA_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${NUMA_INCLUDE_DIRS})
+endif()
@@ -1,7 +1,7 @@
 # - Find TBB
 # Find the Thread Building Blocks library and includes
 #
-# TBB_INCLUDE_DIR - where to find tbb.h, etc.
+# TBB_INCLUDE_DIRS - where to find tbb.h, etc.
 # TBB_LIBRARIES - List of libraries when using TBB.
 # TBB_FOUND - True if TBB found.

@@ -9,17 +9,25 @@ if(NOT DEFINED TBB_ROOT_DIR)
  set(TBB_ROOT_DIR "$ENV{TBBROOT}")
 endif()

-find_path(TBB_INCLUDE_DIR
-NAMES tbb/tbb.h
-HINTS ${TBB_ROOT_DIR}/include)
+find_path(TBB_INCLUDE_DIRS
+  NAMES tbb/tbb.h
+  HINTS ${TBB_ROOT_DIR}/include)

 find_library(TBB_LIBRARIES
-NAMES tbb
-HINTS ${TBB_ROOT_DIR}/lib ENV LIBRARY_PATH)
+  NAMES tbb
+  HINTS ${TBB_ROOT_DIR}/lib ENV LIBRARY_PATH)

 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(TBB DEFAULT_MSG TBB_LIBRARIES TBB_INCLUDE_DIR)
+find_package_handle_standard_args(TBB DEFAULT_MSG TBB_LIBRARIES TBB_INCLUDE_DIRS)

 mark_as_advanced(
-TBB_LIBRARIES
-TBB_INCLUDE_DIR)
+  TBB_LIBRARIES
+  TBB_INCLUDE_DIRS)
+
+if(TBB_FOUND AND NOT (TARGET TBB::TBB))
+  add_library (TBB::TBB UNKNOWN IMPORTED)
+  set_target_properties(TBB::TBB
+    PROPERTIES
+      IMPORTED_LOCATION ${TBB_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${TBB_INCLUDE_DIRS})
+endif()
@@ -1,21 +0,0 @@
-# - Find Bzip2
-# Find the bzip2 compression library and includes
-#
-# BZIP2_INCLUDE_DIR - where to find bzlib.h, etc.
-# BZIP2_LIBRARIES - List of libraries when using bzip2.
-# BZIP2_FOUND - True if bzip2 found.
-
-find_path(BZIP2_INCLUDE_DIR
-  NAMES bzlib.h
-  HINTS ${BZIP2_ROOT_DIR}/include)
-
-find_library(BZIP2_LIBRARIES
-  NAMES bz2
-  HINTS ${BZIP2_ROOT_DIR}/lib)
-
-include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(bzip2 DEFAULT_MSG BZIP2_LIBRARIES BZIP2_INCLUDE_DIR)
-
-mark_as_advanced(
-  BZIP2_LIBRARIES
-  BZIP2_INCLUDE_DIR)
@@ -0,0 +1,29 @@
+# - Find gflags library
+# Find the gflags includes and library
+#
+# gflags_INCLUDE_DIR - where to find gflags.h.
+# gflags_LIBRARIES - List of libraries when using gflags.
+# gflags_FOUND - True if gflags found.
+
+find_path(GFLAGS_INCLUDE_DIR
+  NAMES gflags/gflags.h)
+
+find_library(GFLAGS_LIBRARIES
+  NAMES gflags)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(gflags
+  DEFAULT_MSG GFLAGS_LIBRARIES GFLAGS_INCLUDE_DIR)
+
+mark_as_advanced(
+  GFLAGS_LIBRARIES
+  GFLAGS_INCLUDE_DIR)
+
+if(gflags_FOUND AND NOT (TARGET gflags::gflags))
+  add_library(gflags::gflags UNKNOWN IMPORTED)
+  set_target_properties(gflags::gflags
+    PROPERTIES
+      IMPORTED_LOCATION ${GFLAGS_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${GFLAGS_INCLUDE_DIR}
+      IMPORTED_LINK_INTERFACE_LANGUAGES "CXX")
+endif()
@@ -1,21 +1,29 @@
 # - Find Lz4
 # Find the lz4 compression library and includes
 #
-# LZ4_INCLUDE_DIR - where to find lz4.h, etc.
-# LZ4_LIBRARIES - List of libraries when using lz4.
-# LZ4_FOUND - True if lz4 found.
+# lz4_INCLUDE_DIRS - where to find lz4.h, etc.
+# lz4_LIBRARIES - List of libraries when using lz4.
+# lz4_FOUND - True if lz4 found.

-find_path(LZ4_INCLUDE_DIR
+find_path(lz4_INCLUDE_DIRS
  NAMES lz4.h
-  HINTS ${LZ4_ROOT_DIR}/include)
+  HINTS ${lz4_ROOT_DIR}/include)

-find_library(LZ4_LIBRARIES
+find_library(lz4_LIBRARIES
  NAMES lz4
-  HINTS ${LZ4_ROOT_DIR}/lib)
+  HINTS ${lz4_ROOT_DIR}/lib)

 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(lz4 DEFAULT_MSG LZ4_LIBRARIES LZ4_INCLUDE_DIR)
+find_package_handle_standard_args(lz4 DEFAULT_MSG lz4_LIBRARIES lz4_INCLUDE_DIRS)

 mark_as_advanced(
-  LZ4_LIBRARIES
-  LZ4_INCLUDE_DIR)
+  lz4_LIBRARIES
+  lz4_INCLUDE_DIRS)
+
+if(lz4_FOUND AND NOT (TARGET lz4::lz4))
+  add_library(lz4::lz4 UNKNOWN IMPORTED)
+  set_target_properties(lz4::lz4
+    PROPERTIES
+      IMPORTED_LOCATION ${lz4_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${lz4_INCLUDE_DIRS})
+endif()
@@ -1,21 +1,29 @@
 # - Find Snappy
 # Find the snappy compression library and includes
 #
-# SNAPPY_INCLUDE_DIR - where to find snappy.h, etc.
-# SNAPPY_LIBRARIES - List of libraries when using snappy.
-# SNAPPY_FOUND - True if snappy found.
+# snappy_INCLUDE_DIRS - where to find snappy.h, etc.
+# snappy_LIBRARIES - List of libraries when using snappy.
+# snappy_FOUND - True if snappy found.

-find_path(SNAPPY_INCLUDE_DIR
+find_path(snappy_INCLUDE_DIRS
  NAMES snappy.h
-  HINTS ${SNAPPY_ROOT_DIR}/include)
+  HINTS ${snappy_ROOT_DIR}/include)

-find_library(SNAPPY_LIBRARIES
+find_library(snappy_LIBRARIES
  NAMES snappy
-  HINTS ${SNAPPY_ROOT_DIR}/lib)
+  HINTS ${snappy_ROOT_DIR}/lib)

 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(snappy DEFAULT_MSG SNAPPY_LIBRARIES SNAPPY_INCLUDE_DIR)
+find_package_handle_standard_args(snappy DEFAULT_MSG snappy_LIBRARIES snappy_INCLUDE_DIRS)

 mark_as_advanced(
-  SNAPPY_LIBRARIES
-  SNAPPY_INCLUDE_DIR)
+  snappy_LIBRARIES
+  snappy_INCLUDE_DIRS)
+
+if(snappy_FOUND AND NOT (TARGET snappy::snappy))
+  add_library (snappy::snappy UNKNOWN IMPORTED)
+  set_target_properties(snappy::snappy
+    PROPERTIES
+      IMPORTED_LOCATION ${snappy_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${snappy_INCLUDE_DIRS})
+endif()
@@ -1,21 +1,29 @@
 # - Find zstd
 # Find the zstd compression library and includes
 #
-# ZSTD_INCLUDE_DIR - where to find zstd.h, etc.
-# ZSTD_LIBRARIES - List of libraries when using zstd.
-# ZSTD_FOUND - True if zstd found.
+# zstd_INCLUDE_DIRS - where to find zstd.h, etc.
+# zstd_LIBRARIES - List of libraries when using zstd.
+# zstd_FOUND - True if zstd found.

-find_path(ZSTD_INCLUDE_DIR
+find_path(zstd_INCLUDE_DIRS
  NAMES zstd.h
-  HINTS ${ZSTD_ROOT_DIR}/include)
+  HINTS ${zstd_ROOT_DIR}/include)

-find_library(ZSTD_LIBRARIES
+find_library(zstd_LIBRARIES
  NAMES zstd
-  HINTS ${ZSTD_ROOT_DIR}/lib)
+  HINTS ${zstd_ROOT_DIR}/lib)

 include(FindPackageHandleStandardArgs)
-find_package_handle_standard_args(zstd DEFAULT_MSG ZSTD_LIBRARIES ZSTD_INCLUDE_DIR)
+find_package_handle_standard_args(zstd DEFAULT_MSG zstd_LIBRARIES zstd_INCLUDE_DIRS)

 mark_as_advanced(
-  ZSTD_LIBRARIES
-  ZSTD_INCLUDE_DIR)
+  zstd_LIBRARIES
+  zstd_INCLUDE_DIRS)
+
+if(zstd_FOUND AND NOT (TARGET zstd::zstd))
+  add_library (zstd::zstd UNKNOWN IMPORTED)
+  set_target_properties(zstd::zstd
+    PROPERTIES
+      IMPORTED_LOCATION ${zstd_LIBRARIES}
+      INTERFACE_INCLUDE_DIRECTORIES ${zstd_INCLUDE_DIRS})
+endif()
@@ -0,0 +1,10 @@
+# Read rocksdb version from version.h header file.
+
+function(get_rocksdb_version version_var)
+  file(READ "${CMAKE_CURRENT_SOURCE_DIR}/include/rocksdb/version.h" version_header_file)
+  foreach(component MAJOR MINOR PATCH)
+    string(REGEX MATCH "#define ROCKSDB_${component} ([0-9]+)" _ ${version_header_file})
+    set(ROCKSDB_VERSION_${component} ${CMAKE_MATCH_1})
+  endforeach()
+  set(${version_var} "${ROCKSDB_VERSION_MAJOR}.${ROCKSDB_VERSION_MINOR}.${ROCKSDB_VERSION_PATCH}" PARENT_SCOPE)
+endfunction()
@@ -0,0 +1,106 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "db/arena_wrapped_db_iter.h"
+#include "memory/arena.h"
+#include "rocksdb/env.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+#include "table/internal_iterator.h"
+#include "table/iterator_wrapper.h"
+#include "util/user_comparator_wrapper.h"
+
+namespace rocksdb {
+
+Status ArenaWrappedDBIter::GetProperty(std::string prop_name,
+                                       std::string* prop) {
+  if (prop_name == "rocksdb.iterator.super-version-number") {
+    // First try to pass the value returned from inner iterator.
+    if (!db_iter_->GetProperty(prop_name, prop).ok()) {
+      *prop = ToString(sv_number_);
+    }
+    return Status::OK();
+  }
+  return db_iter_->GetProperty(prop_name, prop);
+}
+
+void ArenaWrappedDBIter::Init(Env* env, const ReadOptions& read_options,
+                              const ImmutableCFOptions& cf_options,
+                              const MutableCFOptions& mutable_cf_options,
+                              const SequenceNumber& sequence,
+                              uint64_t max_sequential_skip_in_iteration,
+                              uint64_t version_number,
+                              ReadCallback* read_callback, DBImpl* db_impl,
+                              ColumnFamilyData* cfd, bool allow_blob,
+                              bool allow_refresh) {
+  auto mem = arena_.AllocateAligned(sizeof(DBIter));
+  db_iter_ = new (mem) DBIter(env, read_options, cf_options, mutable_cf_options,
+                              cf_options.user_comparator, nullptr, sequence,
+                              true, max_sequential_skip_in_iteration,
+                              read_callback, db_impl, cfd, allow_blob);
+  sv_number_ = version_number;
+  allow_refresh_ = allow_refresh;
+}
+
+Status ArenaWrappedDBIter::Refresh() {
+  if (cfd_ == nullptr || db_impl_ == nullptr || !allow_refresh_) {
+    return Status::NotSupported("Creating renew iterator is not allowed.");
+  }
+  assert(db_iter_ != nullptr);
+  // TODO(yiwu): For last_seq_same_as_publish_seq_==false, this is not the
+  // correct behavior. Will be corrected automatically when we take a snapshot
+  // here for the case of WritePreparedTxnDB.
+  SequenceNumber latest_seq = db_impl_->GetLatestSequenceNumber();
+  uint64_t cur_sv_number = cfd_->GetSuperVersionNumber();
+  if (sv_number_ != cur_sv_number) {
+    Env* env = db_iter_->env();
+    db_iter_->~DBIter();
+    arena_.~Arena();
+    new (&arena_) Arena();
+
+    SuperVersion* sv = cfd_->GetReferencedSuperVersion(db_impl_);
+    if (read_callback_) {
+      read_callback_->Refresh(latest_seq);
+    }
+    Init(env, read_options_, *(cfd_->ioptions()), sv->mutable_cf_options,
+         latest_seq, sv->mutable_cf_options.max_sequential_skip_in_iterations,
+         cur_sv_number, read_callback_, db_impl_, cfd_, allow_blob_,
+         allow_refresh_);
+
+    InternalIterator* internal_iter = db_impl_->NewInternalIterator(
+        read_options_, cfd_, sv, &arena_, db_iter_->GetRangeDelAggregator(),
+        latest_seq);
+    SetIterUnderDBIter(internal_iter);
+  } else {
+    db_iter_->set_sequence(latest_seq);
+    db_iter_->set_valid(false);
+  }
+  return Status::OK();
+}
+
+ArenaWrappedDBIter* NewArenaWrappedDbIterator(
+    Env* env, const ReadOptions& read_options,
+    const ImmutableCFOptions& cf_options,
+    const MutableCFOptions& mutable_cf_options, const SequenceNumber& sequence,
+    uint64_t max_sequential_skip_in_iterations, uint64_t version_number,
+    ReadCallback* read_callback, DBImpl* db_impl, ColumnFamilyData* cfd,
+    bool allow_blob, bool allow_refresh) {
+  ArenaWrappedDBIter* iter = new ArenaWrappedDBIter();
+  iter->Init(env, read_options, cf_options, mutable_cf_options, sequence,
+             max_sequential_skip_in_iterations, version_number, read_callback,
+             db_impl, cfd, allow_blob, allow_refresh);
+  if (db_impl != nullptr && cfd != nullptr && allow_refresh) {
+    iter->StoreRefreshInfo(read_options, db_impl, cfd, read_callback,
+                           allow_blob);
+  }
+
+  return iter;
+}
+
+}  // namespace rocksdb
@@ -0,0 +1,112 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#pragma once
+#include <stdint.h>
+#include <string>
+#include "db/db_impl/db_impl.h"
+#include "db/db_iter.h"
+#include "db/dbformat.h"
+#include "db/range_del_aggregator.h"
+#include "memory/arena.h"
+#include "options/cf_options.h"
+#include "rocksdb/db.h"
+#include "rocksdb/iterator.h"
+#include "util/autovector.h"
+
+namespace rocksdb {
+
+class Arena;
+
+// A wrapper iterator which wraps DB Iterator and the arena, with which the DB
+// iterator is supposed to be allocated. This class is used as an entry point of
+// a iterator hierarchy whose memory can be allocated inline. In that way,
+// accessing the iterator tree can be more cache friendly. It is also faster
+// to allocate.
+// When using the class's Iterator interface, the behavior is exactly
+// the same as the inner DBIter.
+class ArenaWrappedDBIter : public Iterator {
+ public:
+  virtual ~ArenaWrappedDBIter() { db_iter_->~DBIter(); }
+
+  // Get the arena to be used to allocate memory for DBIter to be wrapped,
+  // as well as child iterators in it.
+  virtual Arena* GetArena() { return &arena_; }
+  virtual ReadRangeDelAggregator* GetRangeDelAggregator() {
+    return db_iter_->GetRangeDelAggregator();
+  }
+
+  // Set the internal iterator wrapped inside the DB Iterator. Usually it is
+  // a merging iterator.
+  virtual void SetIterUnderDBIter(InternalIterator* iter) {
+    static_cast<DBIter*>(db_iter_)->SetIter(iter);
+  }
+
+  virtual bool Valid() const override { return db_iter_->Valid(); }
+  virtual void SeekToFirst() override { db_iter_->SeekToFirst(); }
+  virtual void SeekToLast() override { db_iter_->SeekToLast(); }
+  virtual void Seek(const Slice& target) override { db_iter_->Seek(target); }
+  virtual void SeekForPrev(const Slice& target) override {
+    db_iter_->SeekForPrev(target);
+  }
+  virtual void Next() override { db_iter_->Next(); }
+  virtual void Prev() override { db_iter_->Prev(); }
+  virtual Slice key() const override { return db_iter_->key(); }
+  virtual Slice value() const override { return db_iter_->value(); }
+  virtual Status status() const override { return db_iter_->status(); }
+  bool IsBlob() const { return db_iter_->IsBlob(); }
+
+  virtual Status GetProperty(std::string prop_name, std::string* prop) override;
+
+  virtual Status Refresh() override;
+
+  void Init(Env* env, const ReadOptions& read_options,
+            const ImmutableCFOptions& cf_options,
+            const MutableCFOptions& mutable_cf_options,
+            const SequenceNumber& sequence,
+            uint64_t max_sequential_skip_in_iterations, uint64_t version_number,
+            ReadCallback* read_callback, DBImpl* db_impl, ColumnFamilyData* cfd,
+            bool allow_blob, bool allow_refresh);
+
+  // Store some parameters so we can refresh the iterator at a later point
+  // with these same params
+  void StoreRefreshInfo(const ReadOptions& read_options, DBImpl* db_impl,
+                        ColumnFamilyData* cfd, ReadCallback* read_callback,
+                        bool allow_blob) {
+    read_options_ = read_options;
+    db_impl_ = db_impl;
+    cfd_ = cfd;
+    read_callback_ = read_callback;
+    allow_blob_ = allow_blob;
+  }
+
+ private:
+  DBIter* db_iter_;
+  Arena arena_;
+  uint64_t sv_number_;
+  ColumnFamilyData* cfd_ = nullptr;
+  DBImpl* db_impl_ = nullptr;
+  ReadOptions read_options_;
+  ReadCallback* read_callback_;
+  bool allow_blob_ = false;
+  bool allow_refresh_ = true;
+};
+
+// Generate the arena wrapped iterator class.
+// `db_impl` and `cfd` are used for reneweal. If left null, renewal will not
+// be supported.
+extern ArenaWrappedDBIter* NewArenaWrappedDbIterator(
+    Env* env, const ReadOptions& read_options,
+    const ImmutableCFOptions& cf_options,
+    const MutableCFOptions& mutable_cf_options, const SequenceNumber& sequence,
+    uint64_t max_sequential_skip_in_iterations, uint64_t version_number,
+    ReadCallback* read_callback, DBImpl* db_impl = nullptr,
+    ColumnFamilyData* cfd = nullptr, bool allow_blob = false,
+    bool allow_refresh = true);
+}  // namespace rocksdb
@@ -5,12 +5,14 @@
 #pragma once
 #ifndef ROCKSDB_LITE

+#include <sstream>
+#include <string>
+
 #include "rocksdb/options.h"
 #include "util/coding.h"
 #include "util/string_util.h"

 namespace rocksdb {
-namespace blob_db {

 // BlobIndex is a pointer to the blob and metadata of the blob. The index is
 // stored in base DB as ValueType::kTypeBlobIndex.
@@ -109,6 +111,23 @@ class BlobIndex {
    return Status::OK();
  }

+  std::string DebugString(bool output_hex) const {
+    std::ostringstream oss;
+
+    if (IsInlined()) {
+      oss << "[inlined blob] value:" << value_.ToString(output_hex);
+    } else {
+      oss << "[blob ref] file:" << file_number_ << " offset:" << offset_
+          << " size:" << size_;
+    }
+
+    if (HasTTL()) {
+      oss << " exp:" << expiration_;
+    }
+
+    return oss.str();
+  }
+
  static void EncodeInlinedTTL(std::string* dst, uint64_t expiration,
                               const Slice& value) {
    assert(dst != nullptr);
@@ -156,6 +175,5 @@ class BlobIndex {
  CompressionType compression_ = kNoCompression;
 };

-}  // namespace blob_db
 }  // namespace rocksdb
 #endif  // ROCKSDB_LITE
@@ -22,6 +22,8 @@
 #include "db/table_cache.h"
 #include "db/version_edit.h"
 #include "file/filename.h"
+#include "file/read_write_util.h"
+#include "file/writable_file_writer.h"
 #include "monitoring/iostats_context_imp.h"
 #include "monitoring/thread_status_util.h"
 #include "rocksdb/db.h"
@@ -33,7 +35,6 @@
 #include "table/format.h"
 #include "table/internal_iterator.h"
 #include "test_util/sync_point.h"
-#include "util/file_reader_writer.h"
 #include "util/stop_watch.h"

 namespace rocksdb {
@@ -65,8 +66,9 @@ TableBuilder* NewTableBuilder(
 }

 Status BuildTable(
-    const std::string& dbname, Env* env, const ImmutableCFOptions& ioptions,
-    const MutableCFOptions& mutable_cf_options, const EnvOptions& env_options,
+    const std::string& dbname, Env* env, FileSystem* fs,
+    const ImmutableCFOptions& ioptions,
+    const MutableCFOptions& mutable_cf_options, const FileOptions& file_options,
    TableCache* table_cache, InternalIterator* iter,
    std::vector<std::unique_ptr<FragmentedRangeTombstoneIterator>>
        range_del_iters,
@@ -114,23 +116,23 @@ Status BuildTable(
    compression_opts_for_flush.max_dict_bytes = 0;
    compression_opts_for_flush.zstd_max_train_bytes = 0;
    {
-      std::unique_ptr<WritableFile> file;
+      std::unique_ptr<FSWritableFile> file;
 #ifndef NDEBUG
-      bool use_direct_writes = env_options.use_direct_writes;
+      bool use_direct_writes = file_options.use_direct_writes;
      TEST_SYNC_POINT_CALLBACK("BuildTable:create_file", &use_direct_writes);
 #endif  // !NDEBUG
-      s = NewWritableFile(env, fname, &file, env_options);
+      s = NewWritableFile(fs, fname, &file, file_options);
      if (!s.ok()) {
        EventHelpers::LogAndNotifyTableFileCreationFinished(
            event_logger, ioptions.listeners, dbname, column_family_name, fname,
-            job_id, meta->fd, tp, reason, s);
+            job_id, meta->fd, kInvalidBlobFileNumber, tp, reason, s);
        return s;
      }
      file->SetIOPriority(io_priority);
      file->SetWriteLifeTimeHint(write_hint);

      file_writer.reset(
-          new WritableFileWriter(std::move(file), fname, env_options, env,
+          new WritableFileWriter(std::move(file), fname, file_options, env,
                                 ioptions.statistics, ioptions.listeners));
      builder = NewTableBuilder(
          ioptions, mutable_cf_options, internal_comparator,
@@ -156,8 +158,9 @@ Status BuildTable(
    for (; c_iter.Valid(); c_iter.Next()) {
      const Slice& key = c_iter.key();
      const Slice& value = c_iter.value();
+      const ParsedInternalKey& ikey = c_iter.ikey();
      builder->Add(key, value);
-      meta->UpdateBoundaries(key, c_iter.ikey().sequence);
+      meta->UpdateBoundaries(key, value, ikey.sequence, ikey.type);

      // TODO(noetzli): Update stats after flush, too.
      if (io_priority == Env::IO_HIGH &&
@@ -216,7 +219,7 @@ Status BuildTable(
      // we will regrad this verification as user reads since the goal is
      // to cache it here for further user reads
      std::unique_ptr<InternalIterator> it(table_cache->NewIterator(
-          ReadOptions(), env_options, internal_comparator, *meta,
+          ReadOptions(), file_options, internal_comparator, *meta,
          nullptr /* range_del_agg */,
          mutable_cf_options.prefix_extractor.get(), nullptr,
          (internal_stats == nullptr) ? nullptr
@@ -239,13 +242,16 @@ Status BuildTable(
  }

  if (!s.ok() || meta->fd.GetFileSize() == 0) {
-    env->DeleteFile(fname);
+    fs->DeleteFile(fname, IOOptions(), nullptr);
  }

+  if (meta->fd.GetFileSize() == 0) {
+    fname = "(nil)";
+  }
  // Output to event logger and fire events.
  EventHelpers::LogAndNotifyTableFileCreationFinished(
      event_logger, ioptions.listeners, dbname, column_family_name, fname,
-      job_id, meta->fd, tp, reason, s);
+      job_id, meta->fd, meta->oldest_blob_file_number, tp, reason, s);

  return s;
 }
@@ -62,8 +62,9 @@ TableBuilder* NewTableBuilder(
 // @param column_family_name Name of the column family that is also identified
 //    by column_family_id, or empty string if unknown.
 extern Status BuildTable(
-    const std::string& dbname, Env* env, const ImmutableCFOptions& options,
-    const MutableCFOptions& mutable_cf_options, const EnvOptions& env_options,
+    const std::string& dbname, Env* env, FileSystem* fs,
+    const ImmutableCFOptions& options,
+    const MutableCFOptions& mutable_cf_options, const FileOptions& file_options,
    TableCache* table_cache, InternalIterator* iter,
    std::vector<std::unique_ptr<FragmentedRangeTombstoneIterator>>
        range_del_iters,
@@ -852,6 +852,17 @@ void rocksdb_delete_cf(
        Slice(key, keylen)));
 }

+void rocksdb_delete_range_cf(rocksdb_t* db,
+                             const rocksdb_writeoptions_t* options,
+                             rocksdb_column_family_handle_t* column_family,
+                             const char* start_key, size_t start_key_len,
+                             const char* end_key, size_t end_key_len,
+                             char** errptr) {
+  SaveError(errptr, db->rep->DeleteRange(options->rep, column_family->rep,
+                                         Slice(start_key, start_key_len),
+                                         Slice(end_key, end_key_len)));
+}
+
 void rocksdb_merge(
    rocksdb_t* db,
    const rocksdb_writeoptions_t* options,
@@ -2032,6 +2043,17 @@ void rocksdb_block_based_options_set_index_type(
  options->rep.index_type = static_cast<BlockBasedTableOptions::IndexType>(v);
 }

+void rocksdb_block_based_options_set_data_block_index_type(
+    rocksdb_block_based_table_options_t* options, int v) {
+  options->rep.data_block_index_type =
+          static_cast<BlockBasedTableOptions::DataBlockIndexType>(v);
+}
+
+void rocksdb_block_based_options_set_data_block_hash_ratio(
+    rocksdb_block_based_table_options_t* options, double v) {
+  options->rep.data_block_hash_table_util_ratio = v;
+}
+
 void rocksdb_block_based_options_set_hash_index_allow_collision(
    rocksdb_block_based_table_options_t* options, unsigned char v) {
  options->rep.hash_index_allow_collision = v;
@@ -2272,11 +2294,6 @@ void rocksdb_options_set_max_bytes_for_level_base(
  opt->rep.max_bytes_for_level_base = n;
 }

-void rocksdb_options_set_snap_refresh_nanos(rocksdb_options_t* opt,
-                                            uint64_t n) {
-  opt->rep.snap_refresh_nanos = n;
-}
-
 void rocksdb_options_set_level_compaction_dynamic_level_bytes(
    rocksdb_options_t* opt, unsigned char v) {
  opt->rep.level_compaction_dynamic_level_bytes = v;
@@ -2514,6 +2531,11 @@ void rocksdb_options_set_max_write_buffer_number_to_maintain(
  opt->rep.max_write_buffer_number_to_maintain = n;
 }

+void rocksdb_options_set_max_write_buffer_size_to_maintain(
+    rocksdb_options_t* opt, int64_t n) {
+  opt->rep.max_write_buffer_size_to_maintain = n;
+}
+
 void rocksdb_options_set_enable_pipelined_write(rocksdb_options_t* opt,
                                                unsigned char v) {
  opt->rep.enable_pipelined_write = v;
@@ -3037,7 +3059,16 @@ rocksdb_filterpolicy_t* rocksdb_filterpolicy_create_bloom_format(int bits_per_ke
    bool KeyMayMatch(const Slice& key, const Slice& filter) const override {
      return rep_->KeyMayMatch(key, filter);
    }
-    static void DoNothing(void*) { }
+    // No need to override GetFilterBitsBuilder if this one is overridden
+    rocksdb::FilterBitsBuilder* GetBuilderWithContext(
+        const rocksdb::FilterBuildingContext& context) const override {
+      return rep_->GetBuilderWithContext(context);
+    }
+    rocksdb::FilterBitsReader* GetFilterBitsReader(
+        const Slice& contents) const override {
+      return rep_->GetFilterBitsReader(contents);
+    }
+    static void DoNothing(void*) {}
  };
  Wrapper* wrapper = new Wrapper;
  wrapper->rep_ = NewBloomFilterPolicy(bits_per_key, original_format);
@@ -3219,6 +3250,11 @@ void rocksdb_writeoptions_set_low_pri(
  opt->rep.low_pri = v;
 }

+void rocksdb_writeoptions_set_memtable_insert_hint_per_batch(
+    rocksdb_writeoptions_t* opt, unsigned char v) {
+  opt->rep.memtable_insert_hint_per_batch = v;
+}
+
 rocksdb_compactoptions_t* rocksdb_compactoptions_create() {
  return new rocksdb_compactoptions_t;
 }
@@ -487,8 +487,11 @@ int main(int argc, char** argv) {
  rocksdb_options_set_paranoid_checks(options, 1);
  rocksdb_options_set_max_open_files(options, 10);
  rocksdb_options_set_base_background_compactions(options, 1);
+
  table_options = rocksdb_block_based_options_create();
  rocksdb_block_based_options_set_block_cache(table_options, cache);
+  rocksdb_block_based_options_set_data_block_index_type(table_options, 1);
+  rocksdb_block_based_options_set_data_block_hash_ratio(table_options, 0.75);
  rocksdb_options_set_block_based_table_factory(options, table_options);

  rocksdb_options_set_compression(options, rocksdb_no_compression);
@@ -1048,17 +1051,20 @@ int main(int argc, char** argv) {
  }

  StartPhase("filter");
-  for (run = 0; run < 2; run++) {
-    // First run uses custom filter, second run uses bloom filter
+  for (run = 0; run <= 2; run++) {
+    // First run uses custom filter
+    // Second run uses old block-based bloom filter
+    // Third run uses full bloom filter
    CheckNoError(err);
    rocksdb_filterpolicy_t* policy;
    if (run == 0) {
-      policy = rocksdb_filterpolicy_create(
-          NULL, FilterDestroy, FilterCreate, FilterKeyMatch, NULL, FilterName);
+      policy = rocksdb_filterpolicy_create(NULL, FilterDestroy, FilterCreate,
+                                           FilterKeyMatch, NULL, FilterName);
+    } else if (run == 1) {
+      policy = rocksdb_filterpolicy_create_bloom(8);
    } else {
-      policy = rocksdb_filterpolicy_create_bloom(10);
+      policy = rocksdb_filterpolicy_create_bloom_full(8);
    }
-
    rocksdb_block_based_options_set_filter_policy(table_options, policy);

    // Create new database
@@ -1071,12 +1077,24 @@ int main(int argc, char** argv) {
    CheckNoError(err);
    rocksdb_put(db, woptions, "bar", 3, "barvalue", 8, &err);
    CheckNoError(err);
+
+    {
+      // Add enough keys to get just one reasonably populated Bloom filter
+      const int keys_to_add = 1500;
+      int i;
+      char keybuf[100];
+      for (i = 0; i < keys_to_add; i++) {
+        snprintf(keybuf, sizeof(keybuf), "yes%020d", i);
+        rocksdb_put(db, woptions, keybuf, strlen(keybuf), "val", 3, &err);
+        CheckNoError(err);
+      }
+    }
    rocksdb_compact_range(db, NULL, 0, NULL, 0);

    fake_filter_result = 1;
    CheckGet(db, roptions, "foo", "foovalue");
    CheckGet(db, roptions, "bar", "barvalue");
-    if (phase == 0) {
+    if (run == 0) {
      // Must not find value when custom filter returns false
      fake_filter_result = 0;
      CheckGet(db, roptions, "foo", NULL);
@@ -1086,6 +1104,43 @@ int main(int argc, char** argv) {
      CheckGet(db, roptions, "foo", "foovalue");
      CheckGet(db, roptions, "bar", "barvalue");
    }
+
+    {
+      // Query some keys not added to identify Bloom filter implementation
+      // from false positive queries, using perfcontext to detect Bloom
+      // filter behavior
+      rocksdb_perfcontext_t* perf = rocksdb_perfcontext_create();
+      rocksdb_perfcontext_reset(perf);
+
+      const int keys_to_query = 10000;
+      int i;
+      char keybuf[100];
+      for (i = 0; i < keys_to_query; i++) {
+        fake_filter_result = i % 2;
+        snprintf(keybuf, sizeof(keybuf), "no%020d", i);
+        CheckGet(db, roptions, keybuf, NULL);
+      }
+
+      const int hits =
+          (int)rocksdb_perfcontext_metric(perf, rocksdb_bloom_sst_hit_count);
+      if (run == 0) {
+        // Due to half true, half false with fake filter result
+        CheckCondition(hits == keys_to_query / 2);
+      } else if (run == 1) {
+        // Essentially a fingerprint of the block-based Bloom schema
+        CheckCondition(hits == 241);
+      } else {
+        // Essentially a fingerprint of the full Bloom schema(s),
+        // format_version < 5, which vary for three different CACHE_LINE_SIZEs
+        CheckCondition(hits == 224 || hits == 180 || hits == 125);
+      }
+      CheckCondition(
+          (keys_to_query - hits) ==
+          (int)rocksdb_perfcontext_metric(perf, rocksdb_bloom_sst_miss_count));
+
+      rocksdb_perfcontext_destroy(perf);
+    }
+
    // Reset the policy
    rocksdb_block_based_options_set_filter_policy(table_options, NULL);
    rocksdb_options_set_block_based_table_factory(options, table_options);
@@ -1189,6 +1244,15 @@ int main(int argc, char** argv) {
    rocksdb_put_cf(db, woptions, handles[1], "foo", 3, "hello", 5, &err);
    CheckNoError(err);

+    rocksdb_put_cf(db, woptions, handles[1], "foobar1", 7, "hello1", 6, &err);
+    CheckNoError(err);
+    rocksdb_put_cf(db, woptions, handles[1], "foobar2", 7, "hello2", 6, &err);
+    CheckNoError(err);
+    rocksdb_put_cf(db, woptions, handles[1], "foobar3", 7, "hello3", 6, &err);
+    CheckNoError(err);
+    rocksdb_put_cf(db, woptions, handles[1], "foobar4", 7, "hello4", 6, &err);
+    CheckNoError(err);
+
    rocksdb_flushoptions_t *flush_options = rocksdb_flushoptions_create();
    rocksdb_flushoptions_set_wait(flush_options, 1);
    rocksdb_flush_cf(db, flush_options, handles[1], &err);
@@ -1201,6 +1265,10 @@ int main(int argc, char** argv) {
    rocksdb_delete_cf(db, woptions, handles[1], "foo", 3, &err);
    CheckNoError(err);

+    rocksdb_delete_range_cf(db, woptions, handles[1], "foobar2", 7, "foobar4",
+                            7, &err);
+    CheckNoError(err);
+
    CheckGetCF(db, roptions, handles[1], "foo", NULL);
    CheckPinGetCF(db, roptions, handles[1], "foo", NULL);

@@ -1253,7 +1321,7 @@ int main(int argc, char** argv) {
    for (i = 0; rocksdb_iter_valid(iter) != 0; rocksdb_iter_next(iter)) {
      i++;
    }
-    CheckCondition(i == 1);
+    CheckCondition(i == 3);
    rocksdb_iter_get_error(iter, &err);
    CheckNoError(err);
    rocksdb_iter_destroy(iter);
@@ -1277,7 +1345,7 @@ int main(int argc, char** argv) {
    for (i = 0; rocksdb_iter_valid(iter) != 0; rocksdb_iter_next(iter)) {
      i++;
    }
-    CheckCondition(i == 1);
+    CheckCondition(i == 3);
    rocksdb_iter_get_error(iter, &err);
    CheckNoError(err);
    rocksdb_iter_destroy(iter);
@@ -1467,6 +1535,7 @@ int main(int argc, char** argv) {
       CheckCondition(!rocksdb_iter_valid(iter));

       rocksdb_iter_destroy(iter);
+       rocksdb_readoptions_set_iterate_upper_bound(roptions, NULL, 0);
    }
  }

@@ -9,11 +9,11 @@

 #include "db/column_family.h"

-#include <cinttypes>
-#include <vector>
-#include <string>
 #include <algorithm>
+#include <cinttypes>
 #include <limits>
+#include <string>
+#include <vector>

 #include "db/compaction/compaction_picker.h"
 #include "db/compaction/compaction_picker_fifo.h"
@@ -30,6 +30,7 @@
 #include "memtable/hash_skiplist_rep.h"
 #include "monitoring/thread_status_util.h"
 #include "options/options_helper.h"
+#include "port/port.h"
 #include "table/block_based/block_based_table_factory.h"
 #include "table/merging_iterator.h"
 #include "util/autovector.h"
@@ -59,11 +60,8 @@ ColumnFamilyHandleImpl::~ColumnFamilyHandleImpl() {
    ColumnFamilyOptions initial_cf_options_copy = cfd_->initial_cf_options();
    JobContext job_context(0);
    mutex_->Lock();
-    if (cfd_->Unref()) {
-      bool dropped = cfd_->IsDropped();
-
-      delete cfd_;
-
+    bool dropped = cfd_->IsDropped();
+    if (cfd_->UnrefAndTryDelete()) {
      if (dropped) {
        db_->FindObsoleteFiles(&job_context, false, true);
      }
@@ -162,6 +160,11 @@ Status CheckConcurrentWritesSupported(const ColumnFamilyOptions& cf_options) {
    return Status::InvalidArgument(
        "Memtable doesn't concurrent writes (allow_concurrent_memtable_write)");
  }
+  if (cf_options.max_successive_merges != 0) {
+    return Status::InvalidArgument(
+        "max_successive_merges > 0 is incompatible "
+        "with concurrent writes (allow_concurrent_memtable_write)");
+  }
  return Status::OK();
 }

@@ -187,6 +190,11 @@ Status CheckCFPathsSupported(const DBOptions& db_options,
  return Status::OK();
 }

+namespace {
+const uint64_t kDefaultTtl = 0xfffffffffffffffe;
+const uint64_t kDefaultPeriodicCompSecs = 0xfffffffffffffffe;
+};  // namespace
+
 ColumnFamilyOptions SanitizeOptions(const ImmutableDBOptions& db_options,
                                    const ColumnFamilyOptions& src) {
  ColumnFamilyOptions result = src;
@@ -227,7 +235,14 @@ ColumnFamilyOptions SanitizeOptions(const ImmutableDBOptions& db_options,
  if (result.max_write_buffer_number < 2) {
    result.max_write_buffer_number = 2;
  }
-  if (result.max_write_buffer_number_to_maintain < 0) {
+  // fall back max_write_buffer_number_to_maintain if
+  // max_write_buffer_size_to_maintain is not set
+  if (result.max_write_buffer_size_to_maintain < 0) {
+    result.max_write_buffer_size_to_maintain =
+        result.max_write_buffer_number *
+        static_cast<int64_t>(result.write_buffer_size);
+  } else if (result.max_write_buffer_size_to_maintain == 0 &&
+             result.max_write_buffer_number_to_maintain < 0) {
    result.max_write_buffer_number_to_maintain = result.max_write_buffer_number;
  }
  // bloom filter size shouldn't exceed 1/4 of memtable size.
@@ -335,6 +350,61 @@ ColumnFamilyOptions SanitizeOptions(const ImmutableDBOptions& db_options,
    result.max_compaction_bytes = result.target_file_size_base * 25;
  }

+  bool is_block_based_table =
+      (result.table_factory->Name() == BlockBasedTableFactory().Name());
+
+  const uint64_t kAdjustedTtl = 30 * 24 * 60 * 60;
+  if (result.ttl == kDefaultTtl) {
+    if (is_block_based_table &&
+        result.compaction_style != kCompactionStyleFIFO) {
+      result.ttl = kAdjustedTtl;
+    } else {
+      result.ttl = 0;
+    }
+  }
+
+  const uint64_t kAdjustedPeriodicCompSecs = 30 * 24 * 60 * 60;
+
+  // Turn on periodic compactions and set them to occur once every 30 days if
+  // compaction filters are used and periodic_compaction_seconds is set to the
+  // default value.
+  if (result.compaction_style != kCompactionStyleFIFO) {
+    if ((result.compaction_filter != nullptr ||
+         result.compaction_filter_factory != nullptr) &&
+        result.periodic_compaction_seconds == kDefaultPeriodicCompSecs &&
+        is_block_based_table) {
+      result.periodic_compaction_seconds = kAdjustedPeriodicCompSecs;
+    }
+  } else {
+    // result.compaction_style == kCompactionStyleFIFO
+    if (result.ttl == 0) {
+      if (is_block_based_table) {
+        if (result.periodic_compaction_seconds == kDefaultPeriodicCompSecs) {
+          result.periodic_compaction_seconds = kAdjustedPeriodicCompSecs;
+        }
+        result.ttl = result.periodic_compaction_seconds;
+      }
+    } else if (result.periodic_compaction_seconds != 0) {
+      result.ttl = std::min(result.ttl, result.periodic_compaction_seconds);
+    }
+  }
+
+  // TTL compactions would work similar to Periodic Compactions in Universal in
+  // most of the cases. So, if ttl is set, execute the periodic compaction
+  // codepath.
+  if (result.compaction_style == kCompactionStyleUniversal && result.ttl != 0) {
+    if (result.periodic_compaction_seconds != 0) {
+      result.periodic_compaction_seconds =
+          std::min(result.ttl, result.periodic_compaction_seconds);
+    } else {
+      result.periodic_compaction_seconds = result.ttl;
+    }
+  }
+
+  if (result.periodic_compaction_seconds == kDefaultPeriodicCompSecs) {
+    result.periodic_compaction_seconds = 0;
+  }
+
  return result;
 }

@@ -371,13 +441,18 @@ void SuperVersion::Cleanup() {
    to_delete.push_back(m);
  }
  current->Unref();
+  if (cfd->Unref()) {
+    delete cfd;
+  }
 }

-void SuperVersion::Init(MemTable* new_mem, MemTableListVersion* new_imm,
-                        Version* new_current) {
+void SuperVersion::Init(ColumnFamilyData* new_cfd, MemTable* new_mem,
+                        MemTableListVersion* new_imm, Version* new_current) {
+  cfd = new_cfd;
  mem = new_mem;
  imm = new_imm;
  current = new_current;
+  cfd->Ref();
  mem->Ref();
  imm->Ref();
  current->Ref();
@@ -405,7 +480,7 @@ ColumnFamilyData::ColumnFamilyData(
    uint32_t id, const std::string& name, Version* _dummy_versions,
    Cache* _table_cache, WriteBufferManager* write_buffer_manager,
    const ColumnFamilyOptions& cf_options, const ImmutableDBOptions& db_options,
-    const EnvOptions& env_options, ColumnFamilySet* column_family_set,
+    const FileOptions& file_options, ColumnFamilySet* column_family_set,
    BlockCacheTracer* const block_cache_tracer)
    : id_(id),
      name_(name),
@@ -423,7 +498,8 @@ ColumnFamilyData::ColumnFamilyData(
      write_buffer_manager_(write_buffer_manager),
      mem_(nullptr),
      imm_(ioptions_.min_write_buffer_number_to_merge,
-           ioptions_.max_write_buffer_number_to_maintain),
+           ioptions_.max_write_buffer_number_to_maintain,
+           ioptions_.max_write_buffer_size_to_maintain),
      super_version_(nullptr),
      super_version_number_(0),
      local_sv_(new ThreadLocalPtr(&SuperVersionUnrefHandle)),
@@ -446,7 +522,7 @@ ColumnFamilyData::ColumnFamilyData(
  if (_dummy_versions != nullptr) {
    internal_stats_.reset(
        new InternalStats(ioptions_.num_levels, db_options.env, this));
-    table_cache_.reset(new TableCache(ioptions_, env_options, _table_cache,
+    table_cache_.reset(new TableCache(ioptions_, file_options, _table_cache,
                                      block_cache_tracer));
    if (ioptions_.compaction_style == kCompactionStyleLevel) {
      compaction_picker_.reset(
@@ -512,21 +588,7 @@ ColumnFamilyData::~ColumnFamilyData() {
  // compaction_queue_ and we destroyed it
  assert(!queued_for_flush_);
  assert(!queued_for_compaction_);
-
-  if (super_version_ != nullptr) {
-    // Release SuperVersion reference kept in ThreadLocalPtr.
-    // This must be done outside of mutex_ since unref handler can lock mutex.
-    super_version_->db_mutex->Unlock();
-    local_sv_.reset();
-    super_version_->db_mutex->Lock();
-
-    bool is_last_reference __attribute__((__unused__));
-    is_last_reference = super_version_->Unref();
-    assert(is_last_reference);
-    super_version_->Cleanup();
-    delete super_version_;
-    super_version_ = nullptr;
-  }
+  assert(super_version_ == nullptr);

  if (dummy_versions_ != nullptr) {
    // List must be empty
@@ -546,6 +608,36 @@ ColumnFamilyData::~ColumnFamilyData() {
  }
 }

+bool ColumnFamilyData::UnrefAndTryDelete() {
+  int old_refs = refs_.fetch_sub(1);
+  assert(old_refs > 0);
+
+  if (old_refs == 1) {
+    assert(super_version_ == nullptr);
+    delete this;
+    return true;
+  }
+
+  if (old_refs == 2 && super_version_ != nullptr) {
+    // Only the super_version_ holds me
+    SuperVersion* sv = super_version_;
+    super_version_ = nullptr;
+    // Release SuperVersion reference kept in ThreadLocalPtr.
+    // This must be done outside of mutex_ since unref handler can lock mutex.
+    sv->db_mutex->Unlock();
+    local_sv_.reset();
+    sv->db_mutex->Lock();
+
+    if (sv->Unref()) {
+      // May delete this ColumnFamilyData after calling Cleanup()
+      sv->Cleanup();
+      delete sv;
+      return true;
+    }
+  }
+  return false;
+}
+
 void ColumnFamilyData::SetDropped() {
  // can't drop default CF
  assert(id_ != 0);
@@ -880,8 +972,8 @@ WriteStallCondition ColumnFamilyData::RecalculateWriteStallConditions(
  return write_stall_condition;
 }

-const EnvOptions* ColumnFamilyData::soptions() const {
-  return &(column_family_set_->env_options_);
+const FileOptions* ColumnFamilyData::soptions() const {
+  return &(column_family_set_->file_options_);
 }

 void ColumnFamilyData::SetCurrent(Version* current_version) {
@@ -921,8 +1013,12 @@ bool ColumnFamilyData::NeedsCompaction() const {

 Compaction* ColumnFamilyData::PickCompaction(
    const MutableCFOptions& mutable_options, LogBuffer* log_buffer) {
+  SequenceNumber earliest_mem_seqno =
+      std::min(mem_->GetEarliestSequenceNumber(),
+               imm_.current()->GetEarliestSequenceNumber(false));
  auto* result = compaction_picker_->PickCompaction(
-      GetName(), mutable_options, current_->storage_info(), log_buffer);
+      GetName(), mutable_options, current_->storage_info(), log_buffer,
+      earliest_mem_seqno);
  if (result != nullptr) {
    result->SetInputVersion(current_);
  }
@@ -1007,9 +1103,8 @@ Compaction* ColumnFamilyData::CompactRange(
  return result;
 }

-SuperVersion* ColumnFamilyData::GetReferencedSuperVersion(
-    InstrumentedMutex* db_mutex) {
-  SuperVersion* sv = GetThreadLocalSuperVersion(db_mutex);
+SuperVersion* ColumnFamilyData::GetReferencedSuperVersion(DBImpl* db) {
+  SuperVersion* sv = GetThreadLocalSuperVersion(db);
  sv->Ref();
  if (!ReturnThreadLocalSuperVersion(sv)) {
    // This Unref() corresponds to the Ref() in GetThreadLocalSuperVersion()
@@ -1021,8 +1116,7 @@ SuperVersion* ColumnFamilyData::GetReferencedSuperVersion(
  return sv;
 }

-SuperVersion* ColumnFamilyData::GetThreadLocalSuperVersion(
-    InstrumentedMutex* db_mutex) {
+SuperVersion* ColumnFamilyData::GetThreadLocalSuperVersion(DBImpl* db) {
  // The SuperVersion is cached in thread local storage to avoid acquiring
  // mutex when SuperVersion does not change since the last use. When a new
  // SuperVersion is installed, the compaction or flush thread cleans up
@@ -1049,16 +1143,21 @@ SuperVersion* ColumnFamilyData::GetThreadLocalSuperVersion(

    if (sv && sv->Unref()) {
      RecordTick(ioptions_.statistics, NUMBER_SUPERVERSION_CLEANUPS);
-      db_mutex->Lock();
+      db->mutex()->Lock();
      // NOTE: underlying resources held by superversion (sst files) might
      // not be released until the next background job.
      sv->Cleanup();
-      sv_to_delete = sv;
+      if (db->immutable_db_options().avoid_unnecessary_blocking_io) {
+        db->AddSuperVersionsToFreeQueue(sv);
+        db->SchedulePurge();
+      } else {
+        sv_to_delete = sv;
+      }
    } else {
-      db_mutex->Lock();
+      db->mutex()->Lock();
    }
    sv = super_version_->Ref();
-    db_mutex->Unlock();
+    db->mutex()->Unlock();

    delete sv_to_delete;
  }
@@ -1096,7 +1195,7 @@ void ColumnFamilyData::InstallSuperVersion(
  SuperVersion* new_superversion = sv_context->new_superversion.release();
  new_superversion->db_mutex = db_mutex;
  new_superversion->mutable_cf_options = mutable_cf_options;
-  new_superversion->Init(mem_, imm_.current(), current_);
+  new_superversion->Init(this, mem_, imm_.current(), current_);
  SuperVersion* old_superversion = super_version_;
  super_version_ = new_superversion;
  ++super_version_number_;
@@ -1160,24 +1259,15 @@ Status ColumnFamilyData::ValidateOptions(
    return s;
  }

-  if (cf_options.ttl > 0) {
-    if (db_options.max_open_files != -1) {
-      return Status::NotSupported(
-          "TTL is only supported when files are always "
-          "kept open (set max_open_files = -1). ");
-    }
+  if (cf_options.ttl > 0 && cf_options.ttl != kDefaultTtl) {
    if (cf_options.table_factory->Name() != BlockBasedTableFactory().Name()) {
      return Status::NotSupported(
          "TTL is only supported in Block-Based Table format. ");
    }
  }

-  if (cf_options.periodic_compaction_seconds > 0) {
-    if (db_options.max_open_files != -1) {
-      return Status::NotSupported(
-          "Periodic Compaction is only supported when files are always "
-          "kept open (set max_open_files = -1). ");
-    }
+  if (cf_options.periodic_compaction_seconds > 0 &&
+      cf_options.periodic_compaction_seconds != kDefaultPeriodicCompSecs) {
    if (cf_options.table_factory->Name() != BlockBasedTableFactory().Name()) {
      return Status::NotSupported(
          "Periodic Compaction is only supported in "
@@ -1221,6 +1311,10 @@ Env::WriteLifeTimeHint ColumnFamilyData::CalculateSSTWriteHint(int level) {
  // L1: medium, L2: long, ...
  if (level - base_level >= 2) {
    return Env::WLTH_EXTREME;
+  } else if (level < base_level) {
+    // There is no restriction which prevents level passed in to be smaller
+    // than base_level.
+    return Env::WLTH_MEDIUM;
  }
  return static_cast<Env::WriteLifeTimeHint>(level - base_level +
                            static_cast<int>(Env::WLTH_MEDIUM));
@@ -1253,7 +1347,7 @@ Directory* ColumnFamilyData::GetDataDir(size_t path_id) const {

 ColumnFamilySet::ColumnFamilySet(const std::string& dbname,
                                 const ImmutableDBOptions* db_options,
-                                 const EnvOptions& env_options,
+                                 const FileOptions& file_options,
                                 Cache* table_cache,
                                 WriteBufferManager* write_buffer_manager,
                                 WriteController* write_controller,
@@ -1261,11 +1355,11 @@ ColumnFamilySet::ColumnFamilySet(const std::string& dbname,
    : max_column_family_(0),
      dummy_cfd_(new ColumnFamilyData(
          0, "", nullptr, nullptr, nullptr, ColumnFamilyOptions(), *db_options,
-          env_options, nullptr, block_cache_tracer)),
+          file_options, nullptr, block_cache_tracer)),
      default_cfd_cache_(nullptr),
      db_name_(dbname),
      db_options_(db_options),
-      env_options_(env_options),
+      file_options_(file_options),
      table_cache_(table_cache),
      write_buffer_manager_(write_buffer_manager),
      write_controller_(write_controller),
@@ -1280,14 +1374,12 @@ ColumnFamilySet::~ColumnFamilySet() {
    // cfd destructor will delete itself from column_family_data_
    auto cfd = column_family_data_.begin()->second;
    bool last_ref __attribute__((__unused__));
-    last_ref = cfd->Unref();
+    last_ref = cfd->UnrefAndTryDelete();
    assert(last_ref);
-    delete cfd;
  }
  bool dummy_last_ref __attribute__((__unused__));
-  dummy_last_ref = dummy_cfd_->Unref();
+  dummy_last_ref = dummy_cfd_->UnrefAndTryDelete();
  assert(dummy_last_ref);
-  delete dummy_cfd_;
 }

 ColumnFamilyData* ColumnFamilySet::GetDefault() const {
@@ -1337,7 +1429,7 @@ ColumnFamilyData* ColumnFamilySet::CreateColumnFamily(
  assert(column_families_.find(name) == column_families_.end());
  ColumnFamilyData* new_cfd = new ColumnFamilyData(
      id, name, dummy_versions, table_cache_, write_buffer_manager_, options,
-      *db_options_, env_options_, this, block_cache_tracer_);
+      *db_options_, file_options_, this, block_cache_tracer_);
  column_families_.insert({name, id});
  column_family_data_.insert({id, new_cfd});
  max_column_family_ = std::max(max_column_family_, id);
@@ -198,6 +198,7 @@ class ColumnFamilyHandleInternal : public ColumnFamilyHandleImpl {
 struct SuperVersion {
  // Accessing members of this class is not thread-safe and requires external
  // synchronization (ie db mutex held or on write thread).
+  ColumnFamilyData* cfd;
  MemTable* mem;
  MemTableListVersion* imm;
  Version* current;
@@ -221,8 +222,8 @@ struct SuperVersion {
  // that needs to be deleted in to_delete vector. Unrefing those
  // objects needs to be done in the mutex
  void Cleanup();
-  void Init(MemTable* new_mem, MemTableListVersion* new_imm,
-            Version* new_current);
+  void Init(ColumnFamilyData* new_cfd, MemTable* new_mem,
+            MemTableListVersion* new_imm, Version* new_current);

  // The value of dummy is not actually used. kSVInUse takes its address as a
  // mark in the thread local storage to indicate the SuperVersion is in use
@@ -275,7 +276,7 @@ class ColumnFamilyData {
  // Ref() can only be called from a context where the caller can guarantee
  // that ColumnFamilyData is alive (while holding a non-zero ref already,
  // holding a DB mutex, or as the leader in a write batch group).
-  void Ref() { refs_.fetch_add(1, std::memory_order_relaxed); }
+  void Ref() { refs_.fetch_add(1); }

  // Unref decreases the reference count, but does not handle deletion
  // when the count goes to 0.  If this method returns true then the
@@ -283,11 +284,16 @@ class ColumnFamilyData {
  // FreeDeadColumnFamilies().  Unref() can only be called while holding
  // a DB mutex, or during single-threaded recovery.
  bool Unref() {
-    int old_refs = refs_.fetch_sub(1, std::memory_order_relaxed);
+    int old_refs = refs_.fetch_sub(1);
    assert(old_refs > 0);
    return old_refs == 1;
  }

+  // UnrefAndTryDelete() decreases the reference count and do free if needed,
+  // return true if this is freed else false, UnrefAndTryDelete() can only
+  // be called while holding a DB mutex, or during single-threaded recovery.
+  bool UnrefAndTryDelete();
+
  // SetDropped() can only be called under following conditions:
  // 1) Holding a DB mutex,
  // 2) from single-threaded write thread, AND
@@ -318,7 +324,7 @@ class ColumnFamilyData {
  }
  FlushReason GetFlushReason() const { return flush_reason_; }
  // thread-safe
-  const EnvOptions* soptions() const;
+  const FileOptions* soptions() const;
  const ImmutableCFOptions* ioptions() const { return &ioptions_; }
  // REQUIRES: DB mutex held
  // This returns the MutableCFOptions used by current SuperVersion
@@ -430,11 +436,11 @@ class ColumnFamilyData {
  SuperVersion* GetSuperVersion() { return super_version_; }
  // thread-safe
  // Return a already referenced SuperVersion to be used safely.
-  SuperVersion* GetReferencedSuperVersion(InstrumentedMutex* db_mutex);
+  SuperVersion* GetReferencedSuperVersion(DBImpl* db);
  // thread-safe
  // Get SuperVersion stored in thread local storage. If it does not exist,
  // get a reference from a current SuperVersion.
-  SuperVersion* GetThreadLocalSuperVersion(InstrumentedMutex* db_mutex);
+  SuperVersion* GetThreadLocalSuperVersion(DBImpl* db);
  // Try to return SuperVersion back to thread local storage. Retrun true on
  // success and false on failure. It fails when the thread local storage
  // contains anything other than SuperVersion::kSVInUse flag.
@@ -504,7 +510,7 @@ class ColumnFamilyData {
                   WriteBufferManager* write_buffer_manager,
                   const ColumnFamilyOptions& options,
                   const ImmutableDBOptions& db_options,
-                   const EnvOptions& env_options,
+                   const FileOptions& file_options,
                   ColumnFamilySet* column_family_set,
                   BlockCacheTracer* const block_cache_tracer);

@@ -632,7 +638,7 @@ class ColumnFamilySet {

  ColumnFamilySet(const std::string& dbname,
                  const ImmutableDBOptions* db_options,
-                  const EnvOptions& env_options, Cache* table_cache,
+                  const FileOptions& file_options, Cache* table_cache,
                  WriteBufferManager* write_buffer_manager,
                  WriteController* write_controller,
                  BlockCacheTracer* const block_cache_tracer);
@@ -690,7 +696,7 @@ class ColumnFamilySet {

  const std::string db_name_;
  const ImmutableDBOptions* const db_options_;
-  const EnvOptions env_options_;
+  const FileOptions file_options_;
  Cache* table_cache_;
  WriteBufferManager* write_buffer_manager_;
  WriteController* write_controller_;
@@ -17,9 +17,11 @@
 #include "memtable/hash_skiplist_rep.h"
 #include "options/options_parser.h"
 #include "port/port.h"
+#include "port/stack_trace.h"
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
 #include "rocksdb/iterator.h"
+#include "rocksdb/utilities/object_registry.h"
 #include "test_util/fault_injection_test_env.h"
 #include "test_util/sync_point.h"
 #include "test_util/testharness.h"
@@ -60,8 +62,20 @@ class EnvCounter : public EnvWrapper {

 class ColumnFamilyTestBase : public testing::Test {
 public:
-  ColumnFamilyTestBase(uint32_t format) : rnd_(139), format_(format) {
-    env_ = new EnvCounter(Env::Default());
+  explicit ColumnFamilyTestBase(uint32_t format) : rnd_(139), format_(format) {
+    Env* base_env = Env::Default();
+#ifndef ROCKSDB_LITE
+    const char* test_env_uri = getenv("TEST_ENV_URI");
+    if (test_env_uri) {
+      Env* test_env = nullptr;
+      Status s = Env::LoadEnv(test_env_uri, &test_env, &env_guard_);
+      base_env = test_env;
+      EXPECT_OK(s);
+      EXPECT_NE(Env::Default(), base_env);
+    }
+#endif  // !ROCKSDB_LITE
+    EXPECT_NE(nullptr, base_env);
+    env_ = new EnvCounter(base_env);
    dbname_ = test::PerThreadDBPath("column_family_test");
    db_options_.create_if_missing = true;
    db_options_.fail_if_options_file_error = true;
@@ -532,6 +546,7 @@ class ColumnFamilyTestBase : public testing::Test {
  std::string dbname_;
  DB* db_ = nullptr;
  EnvCounter* env_;
+  std::shared_ptr<Env> env_guard_;
  Random rnd_;
  uint32_t format_;
 };
@@ -1117,22 +1132,25 @@ TEST_P(ColumnFamilyTest, DifferentWriteBufferSizes) {
  default_cf.arena_block_size = 4 * 4096;
  default_cf.max_write_buffer_number = 10;
  default_cf.min_write_buffer_number_to_merge = 1;
-  default_cf.max_write_buffer_number_to_maintain = 0;
+  default_cf.max_write_buffer_size_to_maintain = 0;
  one.write_buffer_size = 200000;
  one.arena_block_size = 4 * 4096;
  one.max_write_buffer_number = 10;
  one.min_write_buffer_number_to_merge = 2;
-  one.max_write_buffer_number_to_maintain = 1;
+  one.max_write_buffer_size_to_maintain =
+      static_cast<int>(one.write_buffer_size);
  two.write_buffer_size = 1000000;
  two.arena_block_size = 4 * 4096;
  two.max_write_buffer_number = 10;
  two.min_write_buffer_number_to_merge = 3;
-  two.max_write_buffer_number_to_maintain = 2;
+  two.max_write_buffer_size_to_maintain =
+      static_cast<int>(two.write_buffer_size);
  three.write_buffer_size = 4096 * 22;
  three.arena_block_size = 4096;
  three.max_write_buffer_number = 10;
  three.min_write_buffer_number_to_merge = 4;
-  three.max_write_buffer_number_to_maintain = -1;
+  three.max_write_buffer_size_to_maintain =
+      static_cast<int>(three.write_buffer_size);

  Reopen({default_cf, one, two, three});

@@ -2347,6 +2365,45 @@ TEST_P(ColumnFamilyTest, ReadDroppedColumnFamily) {
  }
 }

+TEST_P(ColumnFamilyTest, LiveIteratorWithDroppedColumnFamily) {
+  db_options_.create_missing_column_families = true;
+  db_options_.max_open_files = 20;
+  // delete obsolete files always
+  db_options_.delete_obsolete_files_period_micros = 0;
+  Open({"default", "one", "two"});
+  ColumnFamilyOptions options;
+  options.level0_file_num_compaction_trigger = 100;
+  options.level0_slowdown_writes_trigger = 200;
+  options.level0_stop_writes_trigger = 200;
+  options.write_buffer_size = 100000;  // small write buffer size
+  Reopen({options, options, options});
+
+  // 1MB should create ~10 files for each CF
+  int kKeysNum = 10000;
+  PutRandomData(1, kKeysNum, 100);
+
+  {
+    std::unique_ptr<Iterator> iterator(
+        db_->NewIterator(ReadOptions(), handles_[1]));
+    iterator->SeekToFirst();
+
+    DropColumnFamilies({1});
+
+    // Make sure iterator created can still be used.
+    int count = 0;
+    for (; iterator->Valid(); iterator->Next()) {
+      ASSERT_OK(iterator->status());
+      ++count;
+    }
+    ASSERT_OK(iterator->status());
+    ASSERT_EQ(count, kKeysNum);
+  }
+
+  Reopen();
+  Close();
+  Destroy();
+}
+
 TEST_P(ColumnFamilyTest, FlushAndDropRaceCondition) {
  db_options_.create_missing_column_families = true;
  Open({"default", "one"});
@@ -3312,7 +3369,17 @@ TEST_P(ColumnFamilyTest, MultipleCFPathsTest) {

 }  // namespace rocksdb

+#ifdef ROCKSDB_UNITTESTS_WITH_CUSTOM_OBJECTS_FROM_STATIC_LIBS
+extern "C" {
+void RegisterCustomObjects(int argc, char** argv);
+}
+#else
+void RegisterCustomObjects(int /*argc*/, char** /*argv*/) {}
+#endif  // !ROCKSDB_UNITTESTS_WITH_CUSTOM_OBJECTS_FROM_STATIC_LIBS
+
 int main(int argc, char** argv) {
+  rocksdb::port::InstallStackTraceHandler();
  ::testing::InitGoogleTest(&argc, argv);
+  RegisterCustomObjects(argc, argv);
  return RUN_ALL_TESTS();
 }
@@ -387,7 +387,7 @@ TEST_F(CompactFilesTest, GetCompactionJobInfo) {
  auto l0_files_1 = collector->GetFlushedFiles();
  CompactionOptions co;
  co.compression = CompressionType::kLZ4Compression;
-  CompactionJobInfo compaction_job_info;
+  CompactionJobInfo compaction_job_info{};
  ASSERT_OK(
      db->CompactFiles(co, l0_files_1, 0, -1, nullptr, &compaction_job_info));
  ASSERT_EQ(compaction_job_info.base_input_level, 0);
@@ -37,7 +37,7 @@ Status CompactedDBImpl::Get(const ReadOptions& options, ColumnFamilyHandle*,
                            const Slice& key, PinnableSlice* value) {
  GetContext get_context(user_comparator_, nullptr, nullptr, nullptr,
                         GetContext::kNotFound, key, value, nullptr, nullptr,
-                         nullptr, nullptr);
+                         true, nullptr, nullptr);
  LookupKey lkey(key, kMaxSequenceNumber);
  files_.files[FindFile(key)].fd.table_reader->Get(options, lkey.internal_key(),
                                                   &get_context, nullptr);
@@ -70,7 +70,7 @@ std::vector<Status> CompactedDBImpl::MultiGet(const ReadOptions& options,
      std::string& value = (*values)[idx];
      GetContext get_context(user_comparator_, nullptr, nullptr, nullptr,
                             GetContext::kNotFound, keys[idx], &pinnable_val,
-                             nullptr, nullptr, nullptr, nullptr);
+                             nullptr, nullptr, true, nullptr, nullptr);
      LookupKey lkey(keys[idx], kMaxSequenceNumber);
      r->Get(options, lkey.internal_key(), &get_context, nullptr);
      value.assign(pinnable_val.data(), pinnable_val.size());
@@ -14,6 +14,10 @@ namespace rocksdb {
 class CompactedDBImpl : public DBImpl {
 public:
  CompactedDBImpl(const DBOptions& options, const std::string& dbname);
+  // No copying allowed
+  CompactedDBImpl(const CompactedDBImpl&) = delete;
+  void operator=(const CompactedDBImpl&) = delete;
+
  virtual ~CompactedDBImpl();

  static Status Open(const Options& options, const std::string& dbname,
@@ -104,10 +108,6 @@ class CompactedDBImpl : public DBImpl {
  Version* version_;
  const Comparator* user_comparator_;
  LevelFilesBrief files_;
-
-  // No copying allowed
-  CompactedDBImpl(const CompactedDBImpl&);
-  void operator=(const CompactedDBImpl&);
 };
 }
 #endif  // ROCKSDB_LITE
@@ -275,9 +275,7 @@ Compaction::~Compaction() {
    input_version_->Unref();
  }
  if (cfd_ != nullptr) {
-    if (cfd_->Unref()) {
-      delete cfd_;
-    }
+    cfd_->UnrefAndTryDelete();
  }
 }

@@ -545,17 +543,16 @@ bool Compaction::ShouldFormSubcompactions() const {
  }
 }

-uint64_t Compaction::MaxInputFileCreationTime() const {
-  uint64_t max_creation_time = 0;
+uint64_t Compaction::MinInputFileOldestAncesterTime() const {
+  uint64_t min_oldest_ancester_time = port::kMaxUint64;
  for (const auto& file : inputs_[0].files) {
-    if (file->fd.table_reader != nullptr &&
-        file->fd.table_reader->GetTableProperties() != nullptr) {
-      uint64_t creation_time =
-          file->fd.table_reader->GetTableProperties()->creation_time;
-      max_creation_time = std::max(max_creation_time, creation_time);
+    uint64_t oldest_ancester_time = file->TryGetOldestAncesterTime();
+    if (oldest_ancester_time != 0) {
+      min_oldest_ancester_time =
+          std::min(min_oldest_ancester_time, oldest_ancester_time);
    }
  }
-  return max_creation_time;
+  return min_oldest_ancester_time;
 }

 int Compaction::GetInputBaseLevel() const {
@@ -291,7 +291,7 @@ class Compaction {

  uint32_t max_subcompactions() const { return max_subcompactions_; }

-  uint64_t MaxInputFileCreationTime() const;
+  uint64_t MinInputFileOldestAncesterTime() const;

 private:
  // mark (or clear) all files that are being compacted
@@ -3,6 +3,8 @@
 //  COPYING file in the root directory) and Apache 2.0 License
 //  (found in the LICENSE.Apache file in the root directory).

+#include <cinttypes>
+
 #include "db/compaction/compaction_iterator.h"
 #include "db/snapshot_checker.h"
 #include "port/likely.h"
@@ -38,7 +40,8 @@ CompactionIterator::CompactionIterator(
    const CompactionFilter* compaction_filter,
    const std::atomic<bool>* shutting_down,
    const SequenceNumber preserve_deletes_seqnum,
-    SnapshotListFetchCallback* snap_list_callback)
+    const std::atomic<bool>* manual_compaction_paused,
+    const std::shared_ptr<Logger> info_log)
    : CompactionIterator(
          input, cmp, merge_helper, last_sequence, snapshots,
          earliest_write_conflict_snapshot, snapshot_checker, env,
@@ -46,7 +49,7 @@ CompactionIterator::CompactionIterator(
          std::unique_ptr<CompactionProxy>(
              compaction ? new CompactionProxy(compaction) : nullptr),
          compaction_filter, shutting_down, preserve_deletes_seqnum,
-          snap_list_callback) {}
+          manual_compaction_paused, info_log) {}

 CompactionIterator::CompactionIterator(
    InternalIterator* input, const Comparator* cmp, MergeHelper* merge_helper,
@@ -59,7 +62,8 @@ CompactionIterator::CompactionIterator(
    const CompactionFilter* compaction_filter,
    const std::atomic<bool>* shutting_down,
    const SequenceNumber preserve_deletes_seqnum,
-    SnapshotListFetchCallback* snap_list_callback)
+    const std::atomic<bool>* manual_compaction_paused,
+    const std::shared_ptr<Logger> info_log)
    : input_(input),
      cmp_(cmp),
      merge_helper_(merge_helper),
@@ -73,12 +77,13 @@ CompactionIterator::CompactionIterator(
      compaction_(std::move(compaction)),
      compaction_filter_(compaction_filter),
      shutting_down_(shutting_down),
+      manual_compaction_paused_(manual_compaction_paused),
      preserve_deletes_seqnum_(preserve_deletes_seqnum),
      current_user_key_sequence_(0),
      current_user_key_snapshot_(0),
      merge_out_iter_(merge_helper_),
      current_key_committed_(false),
-      snap_list_callback_(snap_list_callback) {
+      info_log_(info_log) {
  assert(compaction_filter_ == nullptr || compaction_ != nullptr);
  assert(snapshots_ != nullptr);
  bottommost_level_ =
@@ -86,7 +91,24 @@ CompactionIterator::CompactionIterator(
  if (compaction_ != nullptr) {
    level_ptrs_ = std::vector<size_t>(compaction_->number_levels(), 0);
  }
-  ProcessSnapshotList();
+  if (snapshots_->size() == 0) {
+    // optimize for fast path if there are no snapshots
+    visible_at_tip_ = true;
+    earliest_snapshot_iter_ = snapshots_->end();
+    earliest_snapshot_ = kMaxSequenceNumber;
+    latest_snapshot_ = 0;
+  } else {
+    visible_at_tip_ = false;
+    earliest_snapshot_iter_ = snapshots_->begin();
+    earliest_snapshot_ = snapshots_->at(0);
+    latest_snapshot_ = snapshots_->back();
+  }
+#ifndef NDEBUG
+  // findEarliestVisibleSnapshot assumes this ordering.
+  for (size_t i = 1; i < snapshots_->size(); ++i) {
+    assert(snapshots_->at(i - 1) < snapshots_->at(i));
+  }
+#endif
  input_->SetPinnedItersMgr(&pinned_iters_mgr_);
  TEST_SYNC_POINT_CALLBACK("CompactionIterator:AfterInit", compaction_.get());
 }
@@ -125,6 +147,11 @@ void CompactionIterator::Next() {
      // MergeUntil stops when it encounters a corrupt key and does not
      // include them in the result, so we expect the keys here to be valid.
      assert(valid_key);
+      if (!valid_key) {
+        ROCKS_LOG_FATAL(info_log_, "Invalid key (%s) in compaction",
+                        key_.ToString(true).c_str());
+      }
+
      // Keep current_key_ in sync.
      current_key_.UpdateInternalKey(ikey_.sequence, ikey_.type);
      key_ = current_key_.GetInternalKey();
@@ -208,33 +235,12 @@ void CompactionIterator::InvokeFilterIfNeeded(bool* need_skip,
  }
 }

-void CompactionIterator::ProcessSnapshotList() {
-#ifndef NDEBUG
-  // findEarliestVisibleSnapshot assumes this ordering.
-  for (size_t i = 1; i < snapshots_->size(); ++i) {
-    assert(snapshots_->at(i - 1) < snapshots_->at(i));
-  }
-#endif
-  if (snapshots_->size() == 0) {
-    // optimize for fast path if there are no snapshots
-    visible_at_tip_ = true;
-    earliest_snapshot_iter_ = snapshots_->end();
-    earliest_snapshot_ = kMaxSequenceNumber;
-    latest_snapshot_ = 0;
-  } else {
-    visible_at_tip_ = false;
-    earliest_snapshot_iter_ = snapshots_->begin();
-    earliest_snapshot_ = snapshots_->at(0);
-    latest_snapshot_ = snapshots_->back();
-  }
-  released_snapshots_.clear();
-}
-
 void CompactionIterator::NextFromInput() {
  at_next_ = false;
  valid_ = false;

-  while (!valid_ && input_->Valid() && !IsShuttingDown()) {
+  while (!valid_ && input_->Valid() && !IsPausingManualCompaction() &&
+         !IsShuttingDown()) {
    key_ = input_->key();
    value_ = input_->value();
    iter_stats_.num_input_records++;
@@ -277,13 +283,6 @@ void CompactionIterator::NextFromInput() {
    // compaction filter). ikey_.user_key is pointing to the copy.
    if (!has_current_user_key_ ||
        !cmp_->Equal(ikey_.user_key, current_user_key_)) {
-      num_keys_++;
-      // Use num_keys_ to reduce the overhead of reading current time
-      if (snap_list_callback_ && snapshots_->size() &&
-          snap_list_callback_->TimeToRefresh(num_keys_)) {
-        snap_list_callback_->Refresh(snapshots_, latest_snapshot_);
-        ProcessSnapshotList();
-      }
      // First occurrence of this user key
      // Copy key for output
      key_ = current_key_.SetInternalKey(key_, &ikey_);
@@ -349,7 +348,18 @@ void CompactionIterator::NextFromInput() {
      // not compact out.  We will keep this Put, but can drop it's data.
      // (See Optimization 3, below.)
      assert(ikey_.type == kTypeValue);
+      if (ikey_.type != kTypeValue) {
+        ROCKS_LOG_FATAL(info_log_,
+                        "Unexpected key type %d for compaction output",
+                        ikey_.type);
+      }
      assert(current_user_key_snapshot_ == last_snapshot);
+      if (current_user_key_snapshot_ != last_snapshot) {
+        ROCKS_LOG_FATAL(info_log_,
+                        "current_user_key_snapshot_ (%" PRIu64
+                        ") != last_snapshot (%" PRIu64 ")",
+                        current_user_key_snapshot_, last_snapshot);
+      }

      value_.clear();
      valid_ = true;
@@ -491,6 +501,12 @@ void CompactionIterator::NextFromInput() {
      // checking since there has already been a record returned for this key
      // in this snapshot.
      assert(last_sequence >= current_user_key_sequence_);
+      if (last_sequence < current_user_key_sequence_) {
+        ROCKS_LOG_FATAL(info_log_,
+                        "last_sequence (%" PRIu64
+                        ") < current_user_key_sequence_ (%" PRIu64 ")",
+                        last_sequence, current_user_key_sequence_);
+      }

      ++iter_stats_.num_record_drop_hidden;  // (A)
      input_->Next();
@@ -574,6 +590,10 @@ void CompactionIterator::NextFromInput() {
        // MergeUntil stops when it encounters a corrupt key and does not
        // include them in the result, so we expect the keys here to valid.
        assert(valid_key);
+        if (!valid_key) {
+          ROCKS_LOG_FATAL(info_log_, "Invalid key (%s) in compaction",
+                          key_.ToString(true).c_str());
+        }
        // Keep current_key_ in sync.
        current_key_.UpdateInternalKey(ikey_.sequence, ikey_.type);
        key_ = current_key_.GetInternalKey();
@@ -612,32 +632,65 @@ void CompactionIterator::NextFromInput() {
  if (!valid_ && IsShuttingDown()) {
    status_ = Status::ShutdownInProgress();
  }
+
+  if (IsPausingManualCompaction()) {
+    status_ = Status::Incomplete(Status::SubCode::kManualCompactionPaused);
+  }
 }

 void CompactionIterator::PrepareOutput() {
-  // Zeroing out the sequence number leads to better compression.
-  // If this is the bottommost level (no files in lower levels)
-  // and the earliest snapshot is larger than this seqno
-  // and the userkey differs from the last userkey in compaction
-  // then we can squash the seqno to zero.
-  //
-  // This is safe for TransactionDB write-conflict checking since transactions
-  // only care about sequence number larger than any active snapshots.
-  //
-  // Can we do the same for levels above bottom level as long as
-  // KeyNotExistsBeyondOutputLevel() return true?
-  if ((compaction_ != nullptr && !compaction_->allow_ingest_behind()) &&
-      ikeyNotNeededForIncrementalSnapshot() && bottommost_level_ && valid_ &&
-      IN_EARLIEST_SNAPSHOT(ikey_.sequence) && ikey_.type != kTypeMerge) {
-    assert(ikey_.type != kTypeDeletion && ikey_.type != kTypeSingleDeletion);
-    ikey_.sequence = 0;
-    current_key_.UpdateInternalKey(0, ikey_.type);
+  if (valid_) {
+    if (compaction_filter_ && ikey_.type == kTypeBlobIndex) {
+      const auto blob_decision = compaction_filter_->PrepareBlobOutput(
+          user_key(), value_, &compaction_filter_value_);
+
+      if (blob_decision == CompactionFilter::BlobDecision::kCorruption) {
+        status_ = Status::Corruption(
+            "Corrupted blob reference encountered during GC");
+        valid_ = false;
+      } else if (blob_decision == CompactionFilter::BlobDecision::kIOError) {
+        status_ = Status::IOError("Could not relocate blob during GC");
+        valid_ = false;
+      } else if (blob_decision ==
+                 CompactionFilter::BlobDecision::kChangeValue) {
+        value_ = compaction_filter_value_;
+      }
+    }
+
+    // Zeroing out the sequence number leads to better compression.
+    // If this is the bottommost level (no files in lower levels)
+    // and the earliest snapshot is larger than this seqno
+    // and the userkey differs from the last userkey in compaction
+    // then we can squash the seqno to zero.
+    //
+    // This is safe for TransactionDB write-conflict checking since transactions
+    // only care about sequence number larger than any active snapshots.
+    //
+    // Can we do the same for levels above bottom level as long as
+    // KeyNotExistsBeyondOutputLevel() return true?
+    if (valid_ && compaction_ != nullptr &&
+        !compaction_->allow_ingest_behind() &&
+        ikeyNotNeededForIncrementalSnapshot() && bottommost_level_ &&
+        IN_EARLIEST_SNAPSHOT(ikey_.sequence) && ikey_.type != kTypeMerge) {
+      assert(ikey_.type != kTypeDeletion && ikey_.type != kTypeSingleDeletion);
+      if (ikey_.type == kTypeDeletion || ikey_.type == kTypeSingleDeletion) {
+        ROCKS_LOG_FATAL(info_log_,
+                        "Unexpected key type %d for seq-zero optimization",
+                        ikey_.type);
+      }
+      ikey_.sequence = 0;
+      current_key_.UpdateInternalKey(0, ikey_.type);
+    }
  }
 }

 inline SequenceNumber CompactionIterator::findEarliestVisibleSnapshot(
    SequenceNumber in, SequenceNumber* prev_snapshot) {
  assert(snapshots_->size());
+  if (snapshots_->size() == 0) {
+    ROCKS_LOG_FATAL(info_log_,
+                    "No snapshot left in findEarliestVisibleSnapshot");
+  }
  auto snapshots_iter = std::lower_bound(
      snapshots_->begin(), snapshots_->end(), in);
  if (snapshots_iter == snapshots_->begin()) {
@@ -645,6 +698,10 @@ inline SequenceNumber CompactionIterator::findEarliestVisibleSnapshot(
  } else {
    *prev_snapshot = *std::prev(snapshots_iter);
    assert(*prev_snapshot < in);
+    if (*prev_snapshot >= in) {
+      ROCKS_LOG_FATAL(info_log_,
+                      "*prev_snapshot >= in in findEarliestVisibleSnapshot");
+    }
  }
  if (snapshot_checker_ == nullptr) {
    return snapshots_iter != snapshots_->end()
@@ -654,6 +711,9 @@ inline SequenceNumber CompactionIterator::findEarliestVisibleSnapshot(
  for (; snapshots_iter != snapshots_->end(); ++snapshots_iter) {
    auto cur = *snapshots_iter;
    assert(in <= cur);
+    if (in > cur) {
+      ROCKS_LOG_FATAL(info_log_, "in > cur in findEarliestVisibleSnapshot");
+    }
    // Skip if cur is in released_snapshots.
    if (has_released_snapshot && released_snapshots_.count(cur) > 0) {
      continue;
@@ -678,9 +738,14 @@ inline bool CompactionIterator::ikeyNotNeededForIncrementalSnapshot() {

 bool CompactionIterator::IsInEarliestSnapshot(SequenceNumber sequence) {
  assert(snapshot_checker_ != nullptr);
-  assert(earliest_snapshot_ == kMaxSequenceNumber ||
-         (earliest_snapshot_iter_ != snapshots_->end() &&
-          *earliest_snapshot_iter_ == earliest_snapshot_));
+  bool pre_condition = (earliest_snapshot_ == kMaxSequenceNumber ||
+                        (earliest_snapshot_iter_ != snapshots_->end() &&
+                         *earliest_snapshot_iter_ == earliest_snapshot_));
+  assert(pre_condition);
+  if (!pre_condition) {
+    ROCKS_LOG_FATAL(info_log_,
+                    "Pre-Condition is not hold in IsInEarliestSnapshot");
+  }
  auto in_snapshot =
      snapshot_checker_->CheckInSnapshot(sequence, earliest_snapshot_);
  while (UNLIKELY(in_snapshot == SnapshotCheckerResult::kSnapshotReleased)) {
@@ -699,6 +764,10 @@ bool CompactionIterator::IsInEarliestSnapshot(SequenceNumber sequence) {
        snapshot_checker_->CheckInSnapshot(sequence, earliest_snapshot_);
  }
  assert(in_snapshot != SnapshotCheckerResult::kSnapshotReleased);
+  if (in_snapshot == SnapshotCheckerResult::kSnapshotReleased) {
+    ROCKS_LOG_FATAL(info_log_,
+                    "Unexpected released snapshot in IsInEarliestSnapshot");
+  }
  return in_snapshot == SnapshotCheckerResult::kInSnapshot;
 }

@@ -21,53 +21,6 @@

 namespace rocksdb {

-// This callback can be used to refresh the snapshot list from the db. It
-// includes logics to exponentially decrease the refresh rate to limit the
-// overhead of refresh.
-class SnapshotListFetchCallback {
- public:
-  SnapshotListFetchCallback(Env* env, uint64_t snap_refresh_nanos,
-                            size_t every_nth_key = 1024)
-      : timer_(env, /*auto restart*/ true),
-        snap_refresh_nanos_(snap_refresh_nanos),
-        every_nth_key_minus_one_(every_nth_key - 1) {
-    assert(every_nth_key > 0);
-    assert((ceil(log2(every_nth_key)) == floor(log2(every_nth_key))));
-  }
-  // Refresh the snapshot list. snapshots will bre replacted with the new list.
-  // max is the upper bound. Note: this function will acquire the db_mutex_.
-  virtual void Refresh(std::vector<SequenceNumber>* snapshots,
-                       SequenceNumber max) = 0;
-  inline bool TimeToRefresh(const size_t key_index) {
-    // skip the key if key_index % every_nth_key (which is of power 2) is not 0.
-    if ((key_index & every_nth_key_minus_one_) != 0) {
-      return false;
-    }
-    const uint64_t elapsed = timer_.ElapsedNanos();
-    auto ret = elapsed > snap_refresh_nanos_;
-    // pre-compute the next time threshold
-    if (ret) {
-      // inc next refresh period exponentially (by x4)
-      auto next_refresh_threshold = snap_refresh_nanos_ << 2;
-      // make sure the shift has not overflown the highest 1 bit
-      snap_refresh_nanos_ =
-          std::max(snap_refresh_nanos_, next_refresh_threshold);
-    }
-    return ret;
-  }
-  static constexpr SnapshotListFetchCallback* kDisabled = nullptr;
-
-  virtual ~SnapshotListFetchCallback() {}
-
- private:
-  // Time since the callback was created
-  StopWatchNano timer_;
-  // The delay before calling ::Refresh. To be increased exponentially.
-  uint64_t snap_refresh_nanos_;
-  // Skip evey nth key. Number n if of power 2. The math will require n-1.
-  const uint64_t every_nth_key_minus_one_;
-};
-
 class CompactionIterator {
 public:
  // A wrapper around Compaction. Has a much smaller interface, only what
@@ -106,32 +59,34 @@ class CompactionIterator {
    const Compaction* compaction_;
  };

-  CompactionIterator(InternalIterator* input, const Comparator* cmp,
-                     MergeHelper* merge_helper, SequenceNumber last_sequence,
-                     std::vector<SequenceNumber>* snapshots,
-                     SequenceNumber earliest_write_conflict_snapshot,
-                     const SnapshotChecker* snapshot_checker, Env* env,
-                     bool report_detailed_time, bool expect_valid_internal_key,
-                     CompactionRangeDelAggregator* range_del_agg,
-                     const Compaction* compaction = nullptr,
-                     const CompactionFilter* compaction_filter = nullptr,
-                     const std::atomic<bool>* shutting_down = nullptr,
-                     const SequenceNumber preserve_deletes_seqnum = 0,
-                     SnapshotListFetchCallback* snap_list_callback = nullptr);
+  CompactionIterator(
+      InternalIterator* input, const Comparator* cmp, MergeHelper* merge_helper,
+      SequenceNumber last_sequence, std::vector<SequenceNumber>* snapshots,
+      SequenceNumber earliest_write_conflict_snapshot,
+      const SnapshotChecker* snapshot_checker, Env* env,
+      bool report_detailed_time, bool expect_valid_internal_key,
+      CompactionRangeDelAggregator* range_del_agg,
+      const Compaction* compaction = nullptr,
+      const CompactionFilter* compaction_filter = nullptr,
+      const std::atomic<bool>* shutting_down = nullptr,
+      const SequenceNumber preserve_deletes_seqnum = 0,
+      const std::atomic<bool>* manual_compaction_paused = nullptr,
+      const std::shared_ptr<Logger> info_log = nullptr);

  // Constructor with custom CompactionProxy, used for tests.
-  CompactionIterator(InternalIterator* input, const Comparator* cmp,
-                     MergeHelper* merge_helper, SequenceNumber last_sequence,
-                     std::vector<SequenceNumber>* snapshots,
-                     SequenceNumber earliest_write_conflict_snapshot,
-                     const SnapshotChecker* snapshot_checker, Env* env,
-                     bool report_detailed_time, bool expect_valid_internal_key,
-                     CompactionRangeDelAggregator* range_del_agg,
-                     std::unique_ptr<CompactionProxy> compaction,
-                     const CompactionFilter* compaction_filter = nullptr,
-                     const std::atomic<bool>* shutting_down = nullptr,
-                     const SequenceNumber preserve_deletes_seqnum = 0,
-                     SnapshotListFetchCallback* snap_list_callback = nullptr);
+  CompactionIterator(
+      InternalIterator* input, const Comparator* cmp, MergeHelper* merge_helper,
+      SequenceNumber last_sequence, std::vector<SequenceNumber>* snapshots,
+      SequenceNumber earliest_write_conflict_snapshot,
+      const SnapshotChecker* snapshot_checker, Env* env,
+      bool report_detailed_time, bool expect_valid_internal_key,
+      CompactionRangeDelAggregator* range_del_agg,
+      std::unique_ptr<CompactionProxy> compaction,
+      const CompactionFilter* compaction_filter = nullptr,
+      const std::atomic<bool>* shutting_down = nullptr,
+      const SequenceNumber preserve_deletes_seqnum = 0,
+      const std::atomic<bool>* manual_compaction_paused = nullptr,
+      const std::shared_ptr<Logger> info_log = nullptr);

  ~CompactionIterator();

@@ -159,8 +114,6 @@ class CompactionIterator {
 private:
  // Processes the input stream to find the next output
  void NextFromInput();
-  // Process snapshots_ and assign related variables
-  void ProcessSnapshotList();

  // Do last preparations before presenting the output to the callee. At this
  // point this only zeroes out the sequence number if possible for better
@@ -195,7 +148,7 @@ class CompactionIterator {
  InternalIterator* input_;
  const Comparator* cmp_;
  MergeHelper* merge_helper_;
-  std::vector<SequenceNumber>* snapshots_;
+  const std::vector<SequenceNumber>* snapshots_;
  // List of snapshots released during compaction.
  // findEarliestVisibleSnapshot() find them out from return of
  // snapshot_checker, and make sure they will not be returned as
@@ -212,6 +165,7 @@ class CompactionIterator {
  std::unique_ptr<CompactionProxy> compaction_;
  const CompactionFilter* compaction_filter_;
  const std::atomic<bool>* shutting_down_;
+  const std::atomic<bool>* manual_compaction_paused_;
  const SequenceNumber preserve_deletes_seqnum_;
  bool bottommost_level_;
  bool valid_ = false;
@@ -270,13 +224,17 @@ class CompactionIterator {
  // Used to avoid purging uncommitted values. The application can specify
  // uncommitted values by providing a SnapshotChecker object.
  bool current_key_committed_;
-  SnapshotListFetchCallback* snap_list_callback_;
-  // number of distinct keys processed
-  size_t num_keys_ = 0;
+  std::shared_ptr<Logger> info_log_;

  bool IsShuttingDown() {
    // This is a best-effort facility, so memory_order_relaxed is sufficient.
    return shutting_down_ && shutting_down_->load(std::memory_order_relaxed);
  }
+
+  bool IsPausingManualCompaction() {
+    // This is a best-effort facility, so memory_order_relaxed is sufficient.
+    return manual_compaction_paused_ &&
+           manual_compaction_paused_->load(std::memory_order_relaxed);
+  }
 };
 }  // namespace rocksdb
@@ -184,7 +184,7 @@ class TestSnapshotChecker : public SnapshotChecker {
 public:
  explicit TestSnapshotChecker(
      SequenceNumber last_committed_sequence,
-      const std::unordered_map<SequenceNumber, SequenceNumber>& snapshots = {})
+      const std::unordered_map<SequenceNumber, SequenceNumber>& snapshots = {{}})
      : last_committed_sequence_(last_committed_sequence),
        snapshots_(snapshots) {}

@@ -7,8 +7,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#include <cinttypes>
 #include <algorithm>
+#include <cinttypes>
 #include <functional>
 #include <list>
 #include <memory>
@@ -34,7 +34,9 @@
 #include "db/range_del_aggregator.h"
 #include "db/version_set.h"
 #include "file/filename.h"
+#include "file/read_write_util.h"
 #include "file/sst_file_manager_impl.h"
+#include "file/writable_file_writer.h"
 #include "logging/log_buffer.h"
 #include "logging/logging.h"
 #include "monitoring/iostats_context_imp.h"
@@ -52,7 +54,6 @@
 #include "table/table_builder.h"
 #include "test_util/sync_point.h"
 #include "util/coding.h"
-#include "util/file_reader_writer.h"
 #include "util/mutexlock.h"
 #include "util/random.h"
 #include "util/stop_watch.h"
@@ -300,7 +301,7 @@ void CompactionJob::AggregateStatistics() {

 CompactionJob::CompactionJob(
    int job_id, Compaction* compaction, const ImmutableDBOptions& db_options,
-    const EnvOptions env_options, VersionSet* versions,
+    const FileOptions& file_options, VersionSet* versions,
    const std::atomic<bool>* shutting_down,
    const SequenceNumber preserve_deletes_seqnum, LogBuffer* log_buffer,
    Directory* db_directory, Directory* output_directory, Statistics* stats,
@@ -310,19 +311,21 @@ CompactionJob::CompactionJob(
    const SnapshotChecker* snapshot_checker, std::shared_ptr<Cache> table_cache,
    EventLogger* event_logger, bool paranoid_file_checks, bool measure_io_stats,
    const std::string& dbname, CompactionJobStats* compaction_job_stats,
-    Env::Priority thread_pri, SnapshotListFetchCallback* snap_list_callback)
+    Env::Priority thread_pri, const std::atomic<bool>* manual_compaction_paused)
    : job_id_(job_id),
      compact_(new CompactionState(compaction)),
      compaction_job_stats_(compaction_job_stats),
      compaction_stats_(compaction->compaction_reason(), 1),
      dbname_(dbname),
      db_options_(db_options),
-      env_options_(env_options),
+      file_options_(file_options),
      env_(db_options.env),
-      env_options_for_read_(
-          env_->OptimizeForCompactionTableRead(env_options, db_options_)),
+      fs_(db_options.fs.get()),
+      file_options_for_read_(
+          fs_->OptimizeForCompactionTableRead(file_options, db_options_)),
      versions_(versions),
      shutting_down_(shutting_down),
+      manual_compaction_paused_(manual_compaction_paused),
      preserve_deletes_seqnum_(preserve_deletes_seqnum),
      log_buffer_(log_buffer),
      db_directory_(db_directory),
@@ -331,7 +334,6 @@ CompactionJob::CompactionJob(
      db_mutex_(db_mutex),
      db_error_handler_(db_error_handler),
      existing_snapshots_(std::move(existing_snapshots)),
-      snap_list_callback_(snap_list_callback),
      earliest_write_conflict_snapshot_(earliest_write_conflict_snapshot),
      snapshot_checker_(snapshot_checker),
      table_cache_(std::move(table_cache)),
@@ -520,7 +522,8 @@ void CompactionJob::GenSubcompactionBoundaries() {
    // to the index block and may incur I/O cost in the process. Unlock db
    // mutex to reduce contention
    db_mutex_->Unlock();
-    uint64_t size = versions_->ApproximateSize(v, a, b, start_lvl, out_lvl + 1,
+    uint64_t size = versions_->ApproximateSize(SizeApproximationOptions(), v, a,
+                                               b, start_lvl, out_lvl + 1,
                                               TableReaderCaller::kCompaction);
    db_mutex_->Lock();
    ranges.emplace_back(a, b, size);
@@ -645,7 +648,7 @@ Status CompactionJob::Run() {
        // we will regard this verification as user reads since the goal is
        // to cache it here for further user reads
        InternalIterator* iter = cfd->table_cache()->NewIterator(
-            ReadOptions(), env_options_, cfd->internal_comparator(),
+            ReadOptions(), file_options_, cfd->internal_comparator(),
            *files_meta[file_idx], /*range_del_agg=*/nullptr, prefix_extractor,
            /*table_reader_ptr=*/nullptr,
            cfd->internal_stats()->GetFileReadHist(
@@ -834,7 +837,7 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
  // Although the v2 aggregator is what the level iterator(s) know about,
  // the AddTombstones calls will be propagated down to the v1 aggregator.
  std::unique_ptr<InternalIterator> input(versions_->MakeInputIterator(
-      sub_compact->compaction, &range_del_agg, env_options_for_read_));
+      sub_compact->compaction, &range_del_agg, file_options_for_read_));

  AutoThreadOperationStageUpdater stage_updater(
      ThreadStatus::STAGE_COMPACTION_PROCESS_KV);
@@ -865,9 +868,13 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
      false /* internal key corruption is expected */,
      existing_snapshots_.empty() ? 0 : existing_snapshots_.back(),
      snapshot_checker_, compact_->compaction->level(),
-      db_options_.statistics.get(), shutting_down_);
+      db_options_.statistics.get());

  TEST_SYNC_POINT("CompactionJob::Run():Inprogress");
+  TEST_SYNC_POINT_CALLBACK(
+      "CompactionJob::Run():PausingManualCompaction:1",
+      reinterpret_cast<void*>(
+          const_cast<std::atomic<bool>*>(manual_compaction_paused_)));

  Slice* start = sub_compact->start;
  Slice* end = sub_compact->end;
@@ -885,9 +892,8 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
      &existing_snapshots_, earliest_write_conflict_snapshot_,
      snapshot_checker_, env_, ShouldReportDetailedTime(env_, stats_), false,
      &range_del_agg, sub_compact->compaction, compaction_filter,
-      shutting_down_, preserve_deletes_seqnum_,
-      // Currently range_del_agg is incompatible with snapshot refresh feature.
-      range_del_agg.IsEmpty() ? snap_list_callback_ : nullptr));
+      shutting_down_, preserve_deletes_seqnum_, manual_compaction_paused_,
+      db_options_.info_log));
  auto c_iter = sub_compact->c_iter.get();
  c_iter->SeekToFirst();
  if (c_iter->Valid() && sub_compact->compaction->output_level() != 0) {
@@ -929,8 +935,9 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
    assert(sub_compact->current_output() != nullptr);
    sub_compact->builder->Add(key, value);
    sub_compact->current_output_file_size = sub_compact->builder->FileSize();
+    const ParsedInternalKey& ikey = c_iter->ikey();
    sub_compact->current_output()->meta.UpdateBoundaries(
-        key, c_iter->ikey().sequence);
+        key, value, ikey.sequence, ikey.type);
    sub_compact->num_output_records++;

    // Close output file if it is big enough. Two possibilities determine it's
@@ -951,7 +958,14 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
      input_status = input->status();
      output_file_ended = true;
    }
+    TEST_SYNC_POINT_CALLBACK(
+        "CompactionJob::Run():PausingManualCompaction:2",
+        reinterpret_cast<void*>(
+            const_cast<std::atomic<bool>*>(manual_compaction_paused_)));
    c_iter->Next();
+    if (c_iter->status().IsManualCompactionPaused()) {
+      break;
+    }
    if (!output_file_ended && c_iter->Valid() &&
        sub_compact->compaction->output_level() != 0 &&
        sub_compact->ShouldStopBefore(c_iter->key(),
@@ -1004,6 +1018,11 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
      shutting_down_->load(std::memory_order_relaxed)) {
    status = Status::ShutdownInProgress("Database shutdown");
  }
+  if ((status.ok() || status.IsColumnFamilyDropped()) &&
+      (manual_compaction_paused_ &&
+       manual_compaction_paused_->load(std::memory_order_relaxed))) {
+    status = Status::Incomplete(Status::SubCode::kManualCompactionPaused);
+  }
  if (status.ok()) {
    status = input->status();
  }
@@ -1333,17 +1352,20 @@ Status CompactionJob::FinishCompactionOutputFile(
  }
  std::string fname;
  FileDescriptor output_fd;
+  uint64_t oldest_blob_file_number = kInvalidBlobFileNumber;
  if (meta != nullptr) {
    fname =
        TableFileName(sub_compact->compaction->immutable_cf_options()->cf_paths,
                      meta->fd.GetNumber(), meta->fd.GetPathId());
    output_fd = meta->fd;
+    oldest_blob_file_number = meta->oldest_blob_file_number;
  } else {
    fname = "(nil)";
  }
  EventHelpers::LogAndNotifyTableFileCreationFinished(
      event_logger_, cfd->ioptions()->listeners, dbname_, cfd->GetName(), fname,
-      job_id_, output_fd, tp, TableFileCreationReason::kCompaction, s);
+      job_id_, output_fd, oldest_blob_file_number, tp,
+      TableFileCreationReason::kCompaction, s);

 #ifndef ROCKSDB_LITE
  // Report new file to SstFileManagerImpl
@@ -1436,13 +1458,13 @@ Status CompactionJob::OpenCompactionOutputFile(
      TableFileCreationReason::kCompaction);
 #endif  // !ROCKSDB_LITE
  // Make the output file
-  std::unique_ptr<WritableFile> writable_file;
+  std::unique_ptr<FSWritableFile> writable_file;
 #ifndef NDEBUG
-  bool syncpoint_arg = env_options_.use_direct_writes;
+  bool syncpoint_arg = file_options_.use_direct_writes;
  TEST_SYNC_POINT_CALLBACK("CompactionJob::OpenCompactionOutputFile",
                           &syncpoint_arg);
 #endif
-  Status s = NewWritableFile(env_, fname, &writable_file, env_options_);
+  Status s = NewWritableFile(fs_, fname, &writable_file, file_options_);
  if (!s.ok()) {
    ROCKS_LOG_ERROR(
        db_options_.info_log,
@@ -1453,33 +1475,12 @@ Status CompactionJob::OpenCompactionOutputFile(
    LogFlush(db_options_.info_log);
    EventHelpers::LogAndNotifyTableFileCreationFinished(
        event_logger_, cfd->ioptions()->listeners, dbname_, cfd->GetName(),
-        fname, job_id_, FileDescriptor(), TableProperties(),
-        TableFileCreationReason::kCompaction, s);
+        fname, job_id_, FileDescriptor(), kInvalidBlobFileNumber,
+        TableProperties(), TableFileCreationReason::kCompaction, s);
    return s;
  }

-  SubcompactionState::Output out;
-  out.meta.fd =
-      FileDescriptor(file_number, sub_compact->compaction->output_path_id(), 0);
-  out.finished = false;
-
-  sub_compact->outputs.push_back(out);
-  writable_file->SetIOPriority(Env::IO_LOW);
-  writable_file->SetWriteLifeTimeHint(write_hint_);
-  writable_file->SetPreallocationBlockSize(static_cast<size_t>(
-      sub_compact->compaction->OutputFilePreallocationSize()));
-  const auto& listeners =
-      sub_compact->compaction->immutable_cf_options()->listeners;
-  sub_compact->outfile.reset(
-      new WritableFileWriter(std::move(writable_file), fname, env_options_,
-                             env_, db_options_.statistics.get(), listeners));
-
-  // If the Column family flag is to only optimize filters for hits,
-  // we can skip creating filters if this is the bottommost_level where
-  // data is going to be found
-  bool skip_filters =
-      cfd->ioptions()->optimize_filters_for_hits && bottommost_level_;
-
+  // Try to figure out the output file's oldest ancester time.
  int64_t temp_current_time = 0;
  auto get_time_status = env_->GetCurrentTime(&temp_current_time);
  // Safe to proceed even if GetCurrentTime fails. So, log and proceed.
@@ -1489,13 +1490,39 @@ Status CompactionJob::OpenCompactionOutputFile(
                   get_time_status.ToString().c_str());
  }
  uint64_t current_time = static_cast<uint64_t>(temp_current_time);
-
-  uint64_t latest_key_time =
-      sub_compact->compaction->MaxInputFileCreationTime();
-  if (latest_key_time == 0) {
-    latest_key_time = current_time;
+  uint64_t oldest_ancester_time =
+      sub_compact->compaction->MinInputFileOldestAncesterTime();
+  if (oldest_ancester_time == port::kMaxUint64) {
+    oldest_ancester_time = current_time;
  }

+  // Initialize a SubcompactionState::Output and add it to sub_compact->outputs
+  {
+    SubcompactionState::Output out;
+    out.meta.fd = FileDescriptor(file_number,
+                                 sub_compact->compaction->output_path_id(), 0);
+    out.meta.oldest_ancester_time = oldest_ancester_time;
+    out.meta.file_creation_time = current_time;
+    out.finished = false;
+    sub_compact->outputs.push_back(out);
+  }
+
+  writable_file->SetIOPriority(Env::IOPriority::IO_LOW);
+  writable_file->SetWriteLifeTimeHint(write_hint_);
+  writable_file->SetPreallocationBlockSize(static_cast<size_t>(
+      sub_compact->compaction->OutputFilePreallocationSize()));
+  const auto& listeners =
+      sub_compact->compaction->immutable_cf_options()->listeners;
+  sub_compact->outfile.reset(
+      new WritableFileWriter(std::move(writable_file), fname, file_options_,
+                             env_, db_options_.statistics.get(), listeners));
+
+  // If the Column family flag is to only optimize filters for hits,
+  // we can skip creating filters if this is the bottommost_level where
+  // data is going to be found
+  bool skip_filters =
+      cfd->ioptions()->optimize_filters_for_hits && bottommost_level_;
+
  sub_compact->builder.reset(NewTableBuilder(
      *cfd->ioptions(), *(sub_compact->compaction->mutable_cf_options()),
      cfd->internal_comparator(), cfd->int_tbl_prop_collector_factories(),
@@ -1503,9 +1530,9 @@ Status CompactionJob::OpenCompactionOutputFile(
      sub_compact->compaction->output_compression(),
      0 /*sample_for_compression */,
      sub_compact->compaction->output_compression_opts(),
-      sub_compact->compaction->output_level(), skip_filters, latest_key_time,
-      0 /* oldest_key_time */, sub_compact->compaction->max_output_file_size(),
-      current_time));
+      sub_compact->compaction->output_level(), skip_filters,
+      oldest_ancester_time, 0 /* oldest_key_time */,
+      sub_compact->compaction->max_output_file_size(), current_time));
  LogFlush(db_options_.info_log);
  return s;
 }
@@ -62,20 +62,23 @@ class VersionSet;
 // if needed.
 class CompactionJob {
 public:
-  CompactionJob(
-      int job_id, Compaction* compaction, const ImmutableDBOptions& db_options,
-      const EnvOptions env_options, VersionSet* versions,
-      const std::atomic<bool>* shutting_down,
-      const SequenceNumber preserve_deletes_seqnum, LogBuffer* log_buffer,
-      Directory* db_directory, Directory* output_directory, Statistics* stats,
-      InstrumentedMutex* db_mutex, ErrorHandler* db_error_handler,
-      std::vector<SequenceNumber> existing_snapshots,
-      SequenceNumber earliest_write_conflict_snapshot,
-      const SnapshotChecker* snapshot_checker,
-      std::shared_ptr<Cache> table_cache, EventLogger* event_logger,
-      bool paranoid_file_checks, bool measure_io_stats,
-      const std::string& dbname, CompactionJobStats* compaction_job_stats,
-      Env::Priority thread_pri, SnapshotListFetchCallback* snap_list_callback);
+  CompactionJob(int job_id, Compaction* compaction,
+                const ImmutableDBOptions& db_options,
+                const FileOptions& file_options, VersionSet* versions,
+                const std::atomic<bool>* shutting_down,
+                const SequenceNumber preserve_deletes_seqnum,
+                LogBuffer* log_buffer, Directory* db_directory,
+                Directory* output_directory, Statistics* stats,
+                InstrumentedMutex* db_mutex, ErrorHandler* db_error_handler,
+                std::vector<SequenceNumber> existing_snapshots,
+                SequenceNumber earliest_write_conflict_snapshot,
+                const SnapshotChecker* snapshot_checker,
+                std::shared_ptr<Cache> table_cache, EventLogger* event_logger,
+                bool paranoid_file_checks, bool measure_io_stats,
+                const std::string& dbname,
+                CompactionJobStats* compaction_job_stats,
+                Env::Priority thread_pri,
+                const std::atomic<bool>* manual_compaction_paused = nullptr);

  ~CompactionJob();

@@ -147,13 +150,15 @@ class CompactionJob {
  // DBImpl state
  const std::string& dbname_;
  const ImmutableDBOptions& db_options_;
-  const EnvOptions env_options_;
+  const FileOptions file_options_;

  Env* env_;
+  FileSystem* fs_;
  // env_option optimized for compaction table reads
-  EnvOptions env_options_for_read_;
+  FileOptions file_options_for_read_;
  VersionSet* versions_;
  const std::atomic<bool>* shutting_down_;
+  const std::atomic<bool>* manual_compaction_paused_;
  const SequenceNumber preserve_deletes_seqnum_;
  LogBuffer* log_buffer_;
  Directory* db_directory_;
@@ -166,7 +171,6 @@ class CompactionJob {
  // entirely within s1 and s2, then the earlier version of k1 can be safely
  // deleted because that version is not visible in any snapshot.
  std::vector<SequenceNumber> existing_snapshots_;
-  SnapshotListFetchCallback* snap_list_callback_;

  // This is the earliest snapshot that could be used for write-conflict
  // checking by a transaction.  For any user-key newer than this snapshot, we
@@ -7,8 +7,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

-#include <cinttypes>
 #include <algorithm>
+#include <cinttypes>
 #include <iostream>
 #include <mutex>
 #include <queue>
@@ -5,17 +5,20 @@

 #ifndef ROCKSDB_LITE

-#include <cinttypes>
 #include <algorithm>
 #include <array>
+#include <cinttypes>
 #include <map>
 #include <string>
 #include <tuple>

+#include "db/blob_index.h"
 #include "db/column_family.h"
 #include "db/compaction/compaction_job.h"
+#include "db/db_impl/db_impl.h"
 #include "db/error_handler.h"
 #include "db/version_set.h"
+#include "file/writable_file_writer.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/db.h"
 #include "rocksdb/options.h"
@@ -23,7 +26,6 @@
 #include "table/mock_table.h"
 #include "test_util/testharness.h"
 #include "test_util/testutil.h"
-#include "util/file_reader_writer.h"
 #include "util/string_util.h"
 #include "utilities/merge_operators.h"

@@ -70,6 +72,7 @@ class CompactionJobTest : public testing::Test {
 public:
  CompactionJobTest()
      : env_(Env::Default()),
+        fs_(std::make_shared<LegacyFileSystemWrapper>(env_)),
        dbname_(test::PerThreadDBPath("compaction_job_test")),
        db_options_(),
        mutable_cf_options_(cf_options_),
@@ -84,6 +87,8 @@ class CompactionJobTest : public testing::Test {
        mock_table_factory_(new mock::MockTableFactory()),
        error_handler_(nullptr, db_options_, &mutex_) {
    EXPECT_OK(env_->CreateDirIfMissing(dbname_));
+    db_options_.env = env_;
+    db_options_.fs = fs_;
    db_options_.db_paths.emplace_back(dbname_,
                                      std::numeric_limits<uint64_t>::max());
  }
@@ -96,11 +101,34 @@ class CompactionJobTest : public testing::Test {
    return TableFileName(db_paths, meta.fd.GetNumber(), meta.fd.GetPathId());
  }

-  std::string KeyStr(const std::string& user_key, const SequenceNumber seq_num,
-      const ValueType t) {
+  static std::string KeyStr(const std::string& user_key,
+                            const SequenceNumber seq_num, const ValueType t) {
    return InternalKey(user_key, seq_num, t).Encode().ToString();
  }

+  static std::string BlobStr(uint64_t blob_file_number, uint64_t offset,
+                             uint64_t size) {
+    std::string blob_index;
+    BlobIndex::EncodeBlob(&blob_index, blob_file_number, offset, size,
+                          kNoCompression);
+    return blob_index;
+  }
+
+  static std::string BlobStrTTL(uint64_t blob_file_number, uint64_t offset,
+                                uint64_t size, uint64_t expiration) {
+    std::string blob_index;
+    BlobIndex::EncodeBlobTTL(&blob_index, expiration, blob_file_number, offset,
+                             size, kNoCompression);
+    return blob_index;
+  }
+
+  static std::string BlobStrInlinedTTL(const Slice& value,
+                                       uint64_t expiration) {
+    std::string blob_index;
+    BlobIndex::EncodeInlinedTTL(&blob_index, expiration, value);
+    return blob_index;
+  }
+
  void AddMockFile(const stl_wrappers::KVMap& contents, int level = 0) {
    assert(contents.size() > 0);

@@ -109,12 +137,13 @@ class CompactionJobTest : public testing::Test {
    InternalKey smallest_key, largest_key;
    SequenceNumber smallest_seqno = kMaxSequenceNumber;
    SequenceNumber largest_seqno = 0;
+    uint64_t oldest_blob_file_number = kInvalidBlobFileNumber;
    for (auto kv : contents) {
      ParsedInternalKey key;
      std::string skey;
      std::string value;
      std::tie(skey, value) = kv;
-      ParseInternalKey(skey, &key);
+      bool parsed = ParseInternalKey(skey, &key);

      smallest_seqno = std::min(smallest_seqno, key.sequence);
      largest_seqno = std::max(largest_seqno, key.sequence);
@@ -131,6 +160,24 @@ class CompactionJobTest : public testing::Test {
      }

      first_key = false;
+
+      if (parsed && key.type == kTypeBlobIndex) {
+        BlobIndex blob_index;
+        const Status s = blob_index.DecodeFrom(value);
+        if (!s.ok()) {
+          continue;
+        }
+
+        if (blob_index.IsInlined() || blob_index.HasTTL() ||
+            blob_index.file_number() == kInvalidBlobFileNumber) {
+          continue;
+        }
+
+        if (oldest_blob_file_number == kInvalidBlobFileNumber ||
+            oldest_blob_file_number > blob_index.file_number()) {
+          oldest_blob_file_number = blob_index.file_number();
+        }
+      }
    }

    uint64_t file_number = versions_->NewFileNumber();
@@ -139,7 +186,8 @@ class CompactionJobTest : public testing::Test {

    VersionEdit edit;
    edit.AddFile(level, file_number, 0, 10, smallest_key, largest_key,
-        smallest_seqno, largest_seqno, false);
+                 smallest_seqno, largest_seqno, false, oldest_blob_file_number,
+                 kUnknownOldestAncesterTime, kUnknownFileCreationTime);

    mutex_.Lock();
    versions_->LogAndApply(versions_->GetColumnFamilySet()->GetDefault(),
@@ -204,8 +252,15 @@ class CompactionJobTest : public testing::Test {
                                   &write_controller_,
                                   /*block_cache_tracer=*/nullptr));
    compaction_job_stats_.Reset();
+    SetIdentityFile(env_, dbname_);

    VersionEdit new_db;
+    if (db_options_.write_dbid_to_manifest) {
+      DBImpl* impl = new DBImpl(DBOptions(), dbname_);
+      std::string db_id;
+      impl->GetDbIdentityFromIdentityFile(&db_id);
+      new_db.SetDBId(db_id);
+    }
    new_db.SetLogNumber(0);
    new_db.SetNextFile(2);
    new_db.SetLastSequence(0);
@@ -215,8 +270,8 @@ class CompactionJobTest : public testing::Test {
    Status s = env_->NewWritableFile(
        manifest, &file, env_->OptimizeForManifestWrite(env_options_));
    ASSERT_OK(s);
-    std::unique_ptr<WritableFileWriter> file_writer(
-        new WritableFileWriter(std::move(file), manifest, env_options_));
+    std::unique_ptr<WritableFileWriter> file_writer(new WritableFileWriter(
+        NewLegacyWritableFileWrapper(std::move(file)), manifest, env_options_));
    {
      log::Writer log(std::move(file_writer), 0, false);
      std::string record;
@@ -243,8 +298,7 @@ class CompactionJobTest : public testing::Test {
      const std::vector<SequenceNumber>& snapshots = {},
      SequenceNumber earliest_write_conflict_snapshot = kMaxSequenceNumber,
      int output_level = 1, bool verify = true,
-      SnapshotListFetchCallback* snapshot_fetcher =
-          SnapshotListFetchCallback::kDisabled) {
+      uint64_t expected_oldest_blob_file_number = kInvalidBlobFileNumber) {
    auto cfd = versions_->GetColumnFamilySet()->GetDefault();

    size_t num_input_files = 0;
@@ -277,7 +331,7 @@ class CompactionJobTest : public testing::Test {
        nullptr, nullptr, &mutex_, &error_handler_, snapshots,
        earliest_write_conflict_snapshot, snapshot_checker, table_cache_,
        &event_logger, false, false, dbname_, &compaction_job_stats_,
-        Env::Priority::USER, snapshot_fetcher);
+        Env::Priority::USER);
    VerifyInitializationOfCompactionJobStats(compaction_job_stats_);

    compaction_job.Prepare();
@@ -290,20 +344,26 @@ class CompactionJobTest : public testing::Test {
    mutex_.Unlock();

    if (verify) {
-      if (expected_results.size() == 0) {
-        ASSERT_GE(compaction_job_stats_.elapsed_micros, 0U);
-        ASSERT_EQ(compaction_job_stats_.num_input_files, num_input_files);
+      ASSERT_GE(compaction_job_stats_.elapsed_micros, 0U);
+      ASSERT_EQ(compaction_job_stats_.num_input_files, num_input_files);
+
+      if (expected_results.empty()) {
        ASSERT_EQ(compaction_job_stats_.num_output_files, 0U);
      } else {
-        ASSERT_GE(compaction_job_stats_.elapsed_micros, 0U);
-        ASSERT_EQ(compaction_job_stats_.num_input_files, num_input_files);
        ASSERT_EQ(compaction_job_stats_.num_output_files, 1U);
        mock_table_factory_->AssertLatestFile(expected_results);
+
+        auto output_files =
+            cfd->current()->storage_info()->LevelFiles(output_level);
+        ASSERT_EQ(output_files.size(), 1);
+        ASSERT_EQ(output_files[0]->oldest_blob_file_number,
+                  expected_oldest_blob_file_number);
      }
    }
  }

  Env* env_;
+  std::shared_ptr<FileSystem> fs_;
  std::string dbname_;
  EnvOptions env_options_;
  ImmutableDBOptions db_options_;
@@ -954,103 +1014,52 @@ TEST_F(CompactionJobTest, CorruptionAfterDeletion) {
  RunCompaction({files}, expected_results);
 }

-// Test the snapshot fetcher in compaction
-TEST_F(CompactionJobTest, SnapshotRefresh) {
-  uint64_t time_seed = env_->NowMicros();
-  printf("time_seed is %" PRIu64 "\n", time_seed);  // would help to reproduce
-  Random64 rand(time_seed);
-  std::vector<SequenceNumber> db_snapshots;
-  class SnapshotListFetchCallbackTest : public SnapshotListFetchCallback {
-   public:
-    SnapshotListFetchCallbackTest(Env* env, Random64& rand,
-                                  std::vector<SequenceNumber>* snapshots)
-        : SnapshotListFetchCallback(env, 0 /*no time delay*/,
-                                    1 /*fetch after each key*/),
-          rand_(rand),
-          snapshots_(snapshots) {}
-    virtual void Refresh(std::vector<SequenceNumber>* snapshots,
-                         SequenceNumber) override {
-      assert(snapshots->size());
-      assert(snapshots_->size());
-      assert(snapshots_->size() == snapshots->size());
-      if (rand_.OneIn(2)) {
-        uint64_t release_index = rand_.Uniform(snapshots_->size());
-        snapshots_->erase(snapshots_->begin() + release_index);
-        *snapshots = *snapshots_;
-      }
-    }
-
-   private:
-    Random64 rand_;
-    std::vector<SequenceNumber>* snapshots_;
-  } snapshot_fetcher(env_, rand, &db_snapshots);
-
-  std::vector<std::pair<const std::string, std::string>> file1_kvs, file2_kvs;
-  std::array<ValueType, 4> types = {kTypeValue, kTypeDeletion,
-                                    kTypeSingleDeletion};
-  SequenceNumber last_seq = 0;
-  for (int i = 1; i < 100; i++) {
-    SequenceNumber seq = last_seq + 1;
-    last_seq = seq;
-    if (rand.OneIn(2)) {
-      auto type = types[rand.Uniform(types.size())];
-      file1_kvs.push_back(
-          {test::KeyStr("k" + ToString(i), seq, type), "v" + ToString(i)});
-    }
-  }
-  auto file1 = mock::MakeMockFile(file1_kvs);
-  for (int i = 1; i < 100; i++) {
-    SequenceNumber seq = last_seq + 1;
-    last_seq++;
-    if (rand.OneIn(2)) {
-      auto type = types[rand.Uniform(types.size())];
-      file2_kvs.push_back(
-          {test::KeyStr("k" + ToString(i), seq, type), "v" + ToString(i)});
-    }
-  }
-  auto file2 = mock::MakeMockFile(file2_kvs);
-  for (SequenceNumber i = 1; i < last_seq + 1; i++) {
-    if (rand.OneIn(5)) {
-      db_snapshots.push_back(i);
-    }
-  }
-
-  const bool kVerify = true;
-  const int output_level_0 = 0;
+TEST_F(CompactionJobTest, OldestBlobFileNumber) {
  NewDB();
+
+  // Note: blob1 is inlined TTL, so it will not be considered for the purposes
+  // of identifying the oldest referenced blob file. Similarly, blob6 will be
+  // ignored because it has TTL and hence refers to a TTL blob file.
+  const stl_wrappers::KVMap::value_type blob1(
+      KeyStr("a", 1U, kTypeBlobIndex), BlobStrInlinedTTL("foo", 1234567890ULL));
+  const stl_wrappers::KVMap::value_type blob2(KeyStr("b", 2U, kTypeBlobIndex),
+                                              BlobStr(59, 123456, 999));
+  const stl_wrappers::KVMap::value_type blob3(KeyStr("c", 3U, kTypeBlobIndex),
+                                              BlobStr(138, 1000, 1 << 8));
+  auto file1 = mock::MakeMockFile({blob1, blob2, blob3});
  AddMockFile(file1);
+
+  const stl_wrappers::KVMap::value_type blob4(KeyStr("d", 4U, kTypeBlobIndex),
+                                              BlobStr(199, 3 << 10, 1 << 20));
+  const stl_wrappers::KVMap::value_type blob5(KeyStr("e", 5U, kTypeBlobIndex),
+                                              BlobStr(19, 6789, 333));
+  const stl_wrappers::KVMap::value_type blob6(
+      KeyStr("f", 6U, kTypeBlobIndex),
+      BlobStrTTL(5, 2048, 1 << 7, 1234567890ULL));
+  auto file2 = mock::MakeMockFile({blob4, blob5, blob6});
  AddMockFile(file2);
-  SetLastSequence(last_seq);
+
+  const stl_wrappers::KVMap::value_type expected_blob1(
+      KeyStr("a", 0U, kTypeBlobIndex), blob1.second);
+  const stl_wrappers::KVMap::value_type expected_blob2(
+      KeyStr("b", 0U, kTypeBlobIndex), blob2.second);
+  const stl_wrappers::KVMap::value_type expected_blob3(
+      KeyStr("c", 0U, kTypeBlobIndex), blob3.second);
+  const stl_wrappers::KVMap::value_type expected_blob4(
+      KeyStr("d", 0U, kTypeBlobIndex), blob4.second);
+  const stl_wrappers::KVMap::value_type expected_blob5(
+      KeyStr("e", 0U, kTypeBlobIndex), blob5.second);
+  const stl_wrappers::KVMap::value_type expected_blob6(
+      KeyStr("f", 0U, kTypeBlobIndex), blob6.second);
+  auto expected_results =
+      mock::MakeMockFile({expected_blob1, expected_blob2, expected_blob3,
+                          expected_blob4, expected_blob5, expected_blob6});
+
+  SetLastSequence(6U);
  auto files = cfd_->current()->storage_info()->LevelFiles(0);
-  // put the output on L0 since it is easier to feed them again to the 2nd
-  // compaction
-  RunCompaction({files}, file1, db_snapshots, kMaxSequenceNumber,
-                output_level_0, !kVerify, &snapshot_fetcher);
-
-  // Now db_snapshots are changed. Run the compaction again without snapshot
-  // fetcher but with the updated snapshot list.
-  compaction_job_stats_.Reset();
-  files = cfd_->current()->storage_info()->LevelFiles(0);
-  RunCompaction({files}, file1, db_snapshots, kMaxSequenceNumber,
-                output_level_0 + 1, !kVerify);
-  // The result should be what we get if we run compaction without snapshot
-  // fetcher on the updated list of snapshots
-  auto expected = mock_table_factory_->output();
-
-  NewDB();
-  AddMockFile(file1);
-  AddMockFile(file2);
-  SetLastSequence(last_seq);
-  files = cfd_->current()->storage_info()->LevelFiles(0);
-  RunCompaction({files}, expected, db_snapshots, kMaxSequenceNumber,
-                output_level_0, !kVerify);
-  // The 2nd compaction above would get rid of useless delete markers. To get
-  // the output here exactly as what we got above after two compactions, we also
-  // run the compaction for 2nd time.
-  compaction_job_stats_.Reset();
-  files = cfd_->current()->storage_info()->LevelFiles(0);
-  RunCompaction({files}, expected, db_snapshots, kMaxSequenceNumber,
-                output_level_0 + 1, !kVerify);
+  RunCompaction({files}, expected_results, std::vector<SequenceNumber>(),
+                kMaxSequenceNumber, /* output_level */ 1, /* verify */ true,
+                /* expected_oldest_blob_file_number */ 19);
 }

 }  // namespace rocksdb
@@ -39,20 +39,41 @@ bool FindIntraL0Compaction(const std::vector<FileMetaData*>& level_files,
                           size_t min_files_to_compact,
                           uint64_t max_compact_bytes_per_del_file,
                           uint64_t max_compaction_bytes,
-                           CompactionInputFiles* comp_inputs) {
-  size_t compact_bytes = static_cast<size_t>(level_files[0]->fd.file_size);
-  uint64_t compensated_compact_bytes = level_files[0]->compensated_file_size;
+                           CompactionInputFiles* comp_inputs,
+                           SequenceNumber earliest_mem_seqno) {
+  // Do not pick ingested file when there is at least one memtable not flushed
+  // which of seqno is overlap with the sst.
+  TEST_SYNC_POINT("FindIntraL0Compaction");
+  size_t start = 0;
+  for (; start < level_files.size(); start++) {
+    if (level_files[start]->being_compacted) {
+      return false;
+    }
+    // If there is no data in memtable, the earliest sequence number would the
+    // largest sequence number in last memtable.
+    // Because all files are sorted in descending order by largest_seqno, so we
+    // only need to check the first one.
+    if (level_files[start]->fd.largest_seqno <= earliest_mem_seqno) {
+      break;
+    }
+  }
+  if (start >= level_files.size()) {
+    return false;
+  }
+  size_t compact_bytes = static_cast<size_t>(level_files[start]->fd.file_size);
+  uint64_t compensated_compact_bytes =
+      level_files[start]->compensated_file_size;
  size_t compact_bytes_per_del_file = port::kMaxSizet;
-  // Compaction range will be [0, span_len).
-  size_t span_len;
+  // Compaction range will be [start, limit).
+  size_t limit;
  // Pull in files until the amount of compaction work per deleted file begins
  // increasing or maximum total compaction size is reached.
  size_t new_compact_bytes_per_del_file = 0;
-  for (span_len = 1; span_len < level_files.size(); ++span_len) {
-    compact_bytes += static_cast<size_t>(level_files[span_len]->fd.file_size);
-    compensated_compact_bytes += level_files[span_len]->compensated_file_size;
-    new_compact_bytes_per_del_file = compact_bytes / span_len;
-    if (level_files[span_len]->being_compacted ||
+  for (limit = start + 1; limit < level_files.size(); ++limit) {
+    compact_bytes += static_cast<size_t>(level_files[limit]->fd.file_size);
+    compensated_compact_bytes += level_files[limit]->compensated_file_size;
+    new_compact_bytes_per_del_file = compact_bytes / (limit - start);
+    if (level_files[limit]->being_compacted ||
        new_compact_bytes_per_del_file > compact_bytes_per_del_file ||
        compensated_compact_bytes > max_compaction_bytes) {
      break;
@@ -60,11 +81,11 @@ bool FindIntraL0Compaction(const std::vector<FileMetaData*>& level_files,
    compact_bytes_per_del_file = new_compact_bytes_per_del_file;
  }

-  if (span_len >= min_files_to_compact &&
+  if ((limit - start) >= min_files_to_compact &&
      compact_bytes_per_del_file < max_compact_bytes_per_del_file) {
    assert(comp_inputs != nullptr);
    comp_inputs->level = 0;
-    for (size_t i = 0; i < span_len; ++i) {
+    for (size_t i = start; i < limit; ++i) {
      comp_inputs->files.push_back(level_files[i]);
    }
    return true;
@@ -54,10 +54,10 @@ class CompactionPicker {
  // Returns nullptr if there is no compaction to be done.
  // Otherwise returns a pointer to a heap-allocated object that
  // describes the compaction.  Caller should delete the result.
-  virtual Compaction* PickCompaction(const std::string& cf_name,
-                                     const MutableCFOptions& mutable_cf_options,
-                                     VersionStorageInfo* vstorage,
-                                     LogBuffer* log_buffer) = 0;
+  virtual Compaction* PickCompaction(
+      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
+      VersionStorageInfo* vstorage, LogBuffer* log_buffer,
+      SequenceNumber earliest_memtable_seqno = kMaxSequenceNumber) = 0;

  // Return a compaction object for compacting the range [begin,end] in
  // the specified level.  Returns nullptr if there is nothing in that
@@ -247,10 +247,11 @@ class NullCompactionPicker : public CompactionPicker {
  virtual ~NullCompactionPicker() {}

  // Always return "nullptr"
-  Compaction* PickCompaction(const std::string& /*cf_name*/,
-                             const MutableCFOptions& /*mutable_cf_options*/,
-                             VersionStorageInfo* /*vstorage*/,
-                             LogBuffer* /*log_buffer*/) override {
+  Compaction* PickCompaction(
+      const std::string& /*cf_name*/,
+      const MutableCFOptions& /*mutable_cf_options*/,
+      VersionStorageInfo* /*vstorage*/, LogBuffer* /* log_buffer */,
+      SequenceNumber /* earliest_memtable_seqno */) override {
    return nullptr;
  }

@@ -292,11 +293,11 @@ class NullCompactionPicker : public CompactionPicker {
 //                                        files. Cannot be nullptr.
 //
 // @return                                true iff compaction was found.
-bool FindIntraL0Compaction(const std::vector<FileMetaData*>& level_files,
-                           size_t min_files_to_compact,
-                           uint64_t max_compact_bytes_per_del_file,
-                           uint64_t max_compaction_bytes,
-                           CompactionInputFiles* comp_inputs);
+bool FindIntraL0Compaction(
+    const std::vector<FileMetaData*>& level_files, size_t min_files_to_compact,
+    uint64_t max_compact_bytes_per_del_file, uint64_t max_compaction_bytes,
+    CompactionInputFiles* comp_inputs,
+    SequenceNumber earliest_mem_seqno = kMaxSequenceNumber);

 CompressionType GetCompressionType(const ImmutableCFOptions& ioptions,
                                   const VersionStorageInfo* vstorage,
@@ -54,6 +54,15 @@ Compaction* FIFOCompactionPicker::PickTTLCompaction(
  }
  const uint64_t current_time = static_cast<uint64_t>(_current_time);

+  if (!level0_compactions_in_progress_.empty()) {
+    ROCKS_LOG_BUFFER(
+        log_buffer,
+        "[%s] FIFO compaction: Already executing compaction. No need "
+        "to run parallel compactions since compactions are very fast",
+        cf_name.c_str());
+    return nullptr;
+  }
+
  std::vector<CompactionInputFiles> inputs;
  inputs.emplace_back();
  inputs[0].level = 0;
@@ -193,7 +202,8 @@ Compaction* FIFOCompactionPicker::PickSizeCompaction(

 Compaction* FIFOCompactionPicker::PickCompaction(
    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-    VersionStorageInfo* vstorage, LogBuffer* log_buffer) {
+    VersionStorageInfo* vstorage, LogBuffer* log_buffer,
+    SequenceNumber /*earliest_memtable_seqno*/) {
  assert(vstorage->num_levels() == 1);

  Compaction* c = nullptr;
@@ -19,10 +19,10 @@ class FIFOCompactionPicker : public CompactionPicker {
                       const InternalKeyComparator* icmp)
      : CompactionPicker(ioptions, icmp) {}

-  virtual Compaction* PickCompaction(const std::string& cf_name,
-                                     const MutableCFOptions& mutable_cf_options,
-                                     VersionStorageInfo* version,
-                                     LogBuffer* log_buffer) override;
+  virtual Compaction* PickCompaction(
+      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
+      VersionStorageInfo* version, LogBuffer* log_buffer,
+      SequenceNumber earliest_memtable_seqno = kMaxSequenceNumber) override;

  virtual Compaction* CompactRange(
      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
@@ -45,12 +45,14 @@ class LevelCompactionBuilder {
 public:
  LevelCompactionBuilder(const std::string& cf_name,
                         VersionStorageInfo* vstorage,
+                         SequenceNumber earliest_mem_seqno,
                         CompactionPicker* compaction_picker,
                         LogBuffer* log_buffer,
                         const MutableCFOptions& mutable_cf_options,
                         const ImmutableCFOptions& ioptions)
      : cf_name_(cf_name),
        vstorage_(vstorage),
+        earliest_mem_seqno_(earliest_mem_seqno),
        compaction_picker_(compaction_picker),
        log_buffer_(log_buffer),
        mutable_cf_options_(mutable_cf_options),
@@ -97,6 +99,7 @@ class LevelCompactionBuilder {

  const std::string& cf_name_;
  VersionStorageInfo* vstorage_;
+  SequenceNumber earliest_mem_seqno_;
  CompactionPicker* compaction_picker_;
  LogBuffer* log_buffer_;
  int start_level_ = -1;
@@ -537,17 +540,19 @@ bool LevelCompactionBuilder::PickIntraL0Compaction() {
    // resort to L0->L0 compaction yet.
    return false;
  }
-  return FindIntraL0Compaction(
-      level_files, kMinFilesForIntraL0Compaction, port::kMaxUint64,
-      mutable_cf_options_.max_compaction_bytes, &start_level_inputs_);
+  return FindIntraL0Compaction(level_files, kMinFilesForIntraL0Compaction,
+                               port::kMaxUint64,
+                               mutable_cf_options_.max_compaction_bytes,
+                               &start_level_inputs_, earliest_mem_seqno_);
 }
 }  // namespace

 Compaction* LevelCompactionPicker::PickCompaction(
    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-    VersionStorageInfo* vstorage, LogBuffer* log_buffer) {
-  LevelCompactionBuilder builder(cf_name, vstorage, this, log_buffer,
-                                 mutable_cf_options, ioptions_);
+    VersionStorageInfo* vstorage, LogBuffer* log_buffer,
+    SequenceNumber earliest_mem_seqno) {
+  LevelCompactionBuilder builder(cf_name, vstorage, earliest_mem_seqno, this,
+                                 log_buffer, mutable_cf_options, ioptions_);
  return builder.PickCompaction();
 }
 }  // namespace rocksdb
@@ -20,10 +20,10 @@ class LevelCompactionPicker : public CompactionPicker {
  LevelCompactionPicker(const ImmutableCFOptions& ioptions,
                        const InternalKeyComparator* icmp)
      : CompactionPicker(ioptions, icmp) {}
-  virtual Compaction* PickCompaction(const std::string& cf_name,
-                                     const MutableCFOptions& mutable_cf_options,
-                                     VersionStorageInfo* vstorage,
-                                     LogBuffer* log_buffer) override;
+  virtual Compaction* PickCompaction(
+      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
+      VersionStorageInfo* vstorage, LogBuffer* log_buffer,
+      SequenceNumber earliest_memtable_seqno = kMaxSequenceNumber) override;

  virtual bool NeedsCompaction(
      const VersionStorageInfo* vstorage) const override;
@@ -57,6 +57,8 @@ class CompactionPickerTest : public testing::Test {
        log_buffer_(InfoLogLevel::INFO_LEVEL, &logger_),
        file_num_(1),
        vstorage_(nullptr) {
+    mutable_cf_options_.ttl = 0;
+    mutable_cf_options_.periodic_compaction_seconds = 0;
    // ioptions_.compaction_pri = kMinOverlappingRatio has its own set of
    // tests to cover.
    ioptions_.compaction_pri = kByCompensatedSize;
@@ -88,15 +90,14 @@ class CompactionPickerTest : public testing::Test {
           SequenceNumber smallest_seq = 100, SequenceNumber largest_seq = 100,
           size_t compensated_file_size = 0) {
    assert(level < vstorage_->num_levels());
-    FileMetaData* f = new FileMetaData;
-    f->fd = FileDescriptor(file_number, path_id, file_size);
-    f->smallest = InternalKey(smallest, smallest_seq, kTypeValue);
-    f->largest = InternalKey(largest, largest_seq, kTypeValue);
-    f->fd.smallest_seqno = smallest_seq;
-    f->fd.largest_seqno = largest_seq;
+    FileMetaData* f = new FileMetaData(
+        file_number, path_id, file_size,
+        InternalKey(smallest, smallest_seq, kTypeValue),
+        InternalKey(largest, largest_seq, kTypeValue), smallest_seq,
+        largest_seq, /* marked_for_compact */ false, kInvalidBlobFileNumber,
+        kUnknownOldestAncesterTime, kUnknownFileCreationTime);
    f->compensated_file_size =
        (compensated_file_size != 0) ? compensated_file_size : file_size;
-    f->refs = 0;
    vstorage_->AddFile(level, f);
    files_.emplace_back(f);
    file_map_.insert({file_number, {f, level}});
@@ -501,6 +502,168 @@ TEST_F(CompactionPickerTest, AllowsTrivialMoveUniversal) {
  ASSERT_TRUE(compaction->is_trivial_move());
 }

+TEST_F(CompactionPickerTest, UniversalPeriodicCompaction1) {
+  // The case where universal periodic compaction can be picked
+  // with some newer files being compacted.
+  const uint64_t kFileSize = 100000;
+
+  mutable_cf_options_.periodic_compaction_seconds = 1000;
+  UniversalCompactionPicker universal_compaction_picker(ioptions_, &icmp_);
+
+  NewVersionStorage(5, kCompactionStyleUniversal);
+
+  Add(0, 1U, "150", "200", kFileSize, 0, 500, 550);
+  Add(0, 2U, "201", "250", kFileSize, 0, 401, 450);
+  Add(0, 4U, "260", "300", kFileSize, 0, 260, 300);
+  Add(3, 5U, "010", "080", kFileSize, 0, 200, 251);
+  Add(4, 3U, "301", "350", kFileSize, 0, 101, 150);
+  Add(4, 6U, "501", "750", kFileSize, 0, 101, 150);
+
+  file_map_[2].first->being_compacted = true;
+  UpdateVersionStorageInfo();
+  vstorage_->TEST_AddFileMarkedForPeriodicCompaction(4, file_map_[3].first);
+
+  std::unique_ptr<Compaction> compaction(
+      universal_compaction_picker.PickCompaction(
+          cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_));
+
+  ASSERT_TRUE(compaction);
+  ASSERT_EQ(4, compaction->output_level());
+  ASSERT_EQ(0, compaction->start_level());
+  ASSERT_EQ(1U, compaction->num_input_files(0));
+}
+
+TEST_F(CompactionPickerTest, UniversalPeriodicCompaction2) {
+  // The case where universal periodic compaction does not
+  // pick up only level to compact if it doesn't cover
+  // any file marked as periodic compaction.
+  const uint64_t kFileSize = 100000;
+
+  mutable_cf_options_.periodic_compaction_seconds = 1000;
+  UniversalCompactionPicker universal_compaction_picker(ioptions_, &icmp_);
+
+  NewVersionStorage(5, kCompactionStyleUniversal);
+
+  Add(0, 1U, "150", "200", kFileSize, 0, 500, 550);
+  Add(3, 5U, "010", "080", kFileSize, 0, 200, 251);
+  Add(4, 3U, "301", "350", kFileSize, 0, 101, 150);
+  Add(4, 6U, "501", "750", kFileSize, 0, 101, 150);
+
+  file_map_[5].first->being_compacted = true;
+  UpdateVersionStorageInfo();
+  vstorage_->TEST_AddFileMarkedForPeriodicCompaction(0, file_map_[1].first);
+
+  std::unique_ptr<Compaction> compaction(
+      universal_compaction_picker.PickCompaction(
+          cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_));
+
+  ASSERT_FALSE(compaction);
+}
+
+TEST_F(CompactionPickerTest, UniversalPeriodicCompaction3) {
+  // The case where universal periodic compaction does not
+  // pick up only the last sorted run which is an L0 file if it isn't
+  // marked as periodic compaction.
+  const uint64_t kFileSize = 100000;
+
+  mutable_cf_options_.periodic_compaction_seconds = 1000;
+  UniversalCompactionPicker universal_compaction_picker(ioptions_, &icmp_);
+
+  NewVersionStorage(5, kCompactionStyleUniversal);
+
+  Add(0, 1U, "150", "200", kFileSize, 0, 500, 550);
+  Add(0, 5U, "010", "080", kFileSize, 0, 200, 251);
+  Add(0, 6U, "501", "750", kFileSize, 0, 101, 150);
+
+  file_map_[5].first->being_compacted = true;
+  UpdateVersionStorageInfo();
+  vstorage_->TEST_AddFileMarkedForPeriodicCompaction(0, file_map_[1].first);
+
+  std::unique_ptr<Compaction> compaction(
+      universal_compaction_picker.PickCompaction(
+          cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_));
+
+  ASSERT_FALSE(compaction);
+}
+
+TEST_F(CompactionPickerTest, UniversalPeriodicCompaction4) {
+  // The case where universal periodic compaction couldn't form
+  // a compaction that inlcudes any file marked for periodic compaction.
+  // Right now we form the compaction anyway if it is more than one
+  // sorted run. Just put the case here to validate that it doesn't
+  // crash.
+  const uint64_t kFileSize = 100000;
+
+  mutable_cf_options_.periodic_compaction_seconds = 1000;
+  UniversalCompactionPicker universal_compaction_picker(ioptions_, &icmp_);
+
+  NewVersionStorage(5, kCompactionStyleUniversal);
+
+  Add(0, 1U, "150", "200", kFileSize, 0, 500, 550);
+  Add(2, 2U, "010", "080", kFileSize, 0, 200, 251);
+  Add(3, 5U, "010", "080", kFileSize, 0, 200, 251);
+  Add(4, 3U, "301", "350", kFileSize, 0, 101, 150);
+  Add(4, 6U, "501", "750", kFileSize, 0, 101, 150);
+
+  file_map_[2].first->being_compacted = true;
+  UpdateVersionStorageInfo();
+  vstorage_->TEST_AddFileMarkedForPeriodicCompaction(0, file_map_[2].first);
+
+  std::unique_ptr<Compaction> compaction(
+      universal_compaction_picker.PickCompaction(
+          cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_));
+  ASSERT_TRUE(!compaction ||
+              compaction->start_level() != compaction->output_level());
+}
+
+TEST_F(CompactionPickerTest, UniversalPeriodicCompaction5) {
+  // Test single L0 file periodic compaction triggering.
+  const uint64_t kFileSize = 100000;
+
+  mutable_cf_options_.periodic_compaction_seconds = 1000;
+  UniversalCompactionPicker universal_compaction_picker(ioptions_, &icmp_);
+
+  NewVersionStorage(5, kCompactionStyleUniversal);
+
+  Add(0, 6U, "150", "200", kFileSize, 0, 500, 550);
+  UpdateVersionStorageInfo();
+  vstorage_->TEST_AddFileMarkedForPeriodicCompaction(0, file_map_[6].first);
+
+  std::unique_ptr<Compaction> compaction(
+      universal_compaction_picker.PickCompaction(
+          cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_));
+  ASSERT_TRUE(compaction);
+  ASSERT_EQ(0, compaction->start_level());
+  ASSERT_EQ(1U, compaction->num_input_files(0));
+  ASSERT_EQ(6U, compaction->input(0, 0)->fd.GetNumber());
+  ASSERT_EQ(4, compaction->output_level());
+}
+
+TEST_F(CompactionPickerTest, UniversalPeriodicCompaction6) {
+  // Test single sorted run non-L0 periodic compaction
+  const uint64_t kFileSize = 100000;
+
+  mutable_cf_options_.periodic_compaction_seconds = 1000;
+  UniversalCompactionPicker universal_compaction_picker(ioptions_, &icmp_);
+
+  NewVersionStorage(5, kCompactionStyleUniversal);
+
+  Add(4, 5U, "150", "200", kFileSize, 0, 500, 550);
+  Add(4, 6U, "350", "400", kFileSize, 0, 500, 550);
+  UpdateVersionStorageInfo();
+  vstorage_->TEST_AddFileMarkedForPeriodicCompaction(4, file_map_[6].first);
+
+  std::unique_ptr<Compaction> compaction(
+      universal_compaction_picker.PickCompaction(
+          cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_));
+  ASSERT_TRUE(compaction);
+  ASSERT_EQ(4, compaction->start_level());
+  ASSERT_EQ(2U, compaction->num_input_files(0));
+  ASSERT_EQ(5U, compaction->input(0, 0)->fd.GetNumber());
+  ASSERT_EQ(6U, compaction->input(0, 1)->fd.GetNumber());
+  ASSERT_EQ(4, compaction->output_level());
+}
+
 TEST_F(CompactionPickerTest, NeedsCompactionFIFO) {
  NewVersionStorage(1, kCompactionStyleFIFO);
  const int kFileCount =
@@ -1488,12 +1651,12 @@ TEST_F(CompactionPickerTest, IntraL0MaxCompactionBytesNotHit) {
  // All 5 L0 files will be picked for intra L0 compaction. The one L1 file
  // spans entire L0 key range and is marked as being compacted to avoid
  // L0->L1 compaction.
-  Add(0, 1U, "100", "150", 200000U);
-  Add(0, 2U, "151", "200", 200000U);
-  Add(0, 3U, "201", "250", 200000U);
-  Add(0, 4U, "251", "300", 200000U);
-  Add(0, 5U, "301", "350", 200000U);
-  Add(1, 6U, "100", "350", 200000U);
+  Add(0, 1U, "100", "150", 200000U, 0, 100, 101);
+  Add(0, 2U, "151", "200", 200000U, 0, 102, 103);
+  Add(0, 3U, "201", "250", 200000U, 0, 104, 105);
+  Add(0, 4U, "251", "300", 200000U, 0, 106, 107);
+  Add(0, 5U, "301", "350", 200000U, 0, 108, 109);
+  Add(1, 6U, "100", "350", 200000U, 0, 110, 111);
  vstorage_->LevelFiles(1)[0]->being_compacted = true;
  UpdateVersionStorageInfo();

@@ -1504,7 +1667,7 @@ TEST_F(CompactionPickerTest, IntraL0MaxCompactionBytesNotHit) {
  ASSERT_EQ(5U, compaction->num_input_files(0));
  ASSERT_EQ(CompactionReason::kLevelL0FilesNum,
            compaction->compaction_reason());
-  ASSERT_EQ(0U, compaction->output_level());
+  ASSERT_EQ(0, compaction->output_level());
 }

 TEST_F(CompactionPickerTest, IntraL0MaxCompactionBytesHit) {
@@ -1518,12 +1681,12 @@ TEST_F(CompactionPickerTest, IntraL0MaxCompactionBytesHit) {
  // max_compaction_bytes limit (the minimum number of files for triggering
  // intra L0 compaction is 4). The one L1 file spans entire L0 key range and
  // is marked as being compacted to avoid L0->L1 compaction.
-  Add(0, 1U, "100", "150", 200000U);
-  Add(0, 2U, "151", "200", 200000U);
-  Add(0, 3U, "201", "250", 200000U);
-  Add(0, 4U, "251", "300", 200000U);
-  Add(0, 5U, "301", "350", 200000U);
-  Add(1, 6U, "100", "350", 200000U);
+  Add(0, 1U, "100", "150", 200000U, 0, 100, 101);
+  Add(0, 2U, "151", "200", 200000U, 0, 102, 103);
+  Add(0, 3U, "201", "250", 200000U, 0, 104, 105);
+  Add(0, 4U, "251", "300", 200000U, 0, 106, 107);
+  Add(0, 5U, "301", "350", 200000U, 0, 108, 109);
+  Add(1, 6U, "100", "350", 200000U, 0, 109, 110);
  vstorage_->LevelFiles(1)[0]->being_compacted = true;
  UpdateVersionStorageInfo();

@@ -1534,7 +1697,39 @@ TEST_F(CompactionPickerTest, IntraL0MaxCompactionBytesHit) {
  ASSERT_EQ(4U, compaction->num_input_files(0));
  ASSERT_EQ(CompactionReason::kLevelL0FilesNum,
            compaction->compaction_reason());
-  ASSERT_EQ(0U, compaction->output_level());
+  ASSERT_EQ(0, compaction->output_level());
+}
+
+TEST_F(CompactionPickerTest, IntraL0ForEarliestSeqno) {
+  // Intra L0 compaction triggers only if there are at least
+  // level0_file_num_compaction_trigger + 2 L0 files.
+  mutable_cf_options_.level0_file_num_compaction_trigger = 3;
+  mutable_cf_options_.max_compaction_bytes = 999999u;
+  NewVersionStorage(6, kCompactionStyleLevel);
+
+  // 4 out of 6 L0 files will be picked for intra L0 compaction due to
+  // being_compact limit. And the latest one L0 will be skipped due to earliest
+  // seqno. The one L1 file spans entire L0 key range and is marked as being
+  // compacted to avoid L0->L1 compaction.
+  Add(1, 1U, "100", "350", 200000U, 0, 110, 111);
+  Add(0, 2U, "301", "350", 1U, 0, 108, 109);
+  Add(0, 3U, "251", "300", 1U, 0, 106, 107);
+  Add(0, 4U, "201", "250", 1U, 0, 104, 105);
+  Add(0, 5U, "151", "200", 1U, 0, 102, 103);
+  Add(0, 6U, "100", "150", 1U, 0, 100, 101);
+  Add(0, 7U, "100", "100", 1U, 0, 99, 100);
+  vstorage_->LevelFiles(0)[5]->being_compacted = true;
+  vstorage_->LevelFiles(1)[0]->being_compacted = true;
+  UpdateVersionStorageInfo();
+
+  std::unique_ptr<Compaction> compaction(level_compaction_picker.PickCompaction(
+      cf_name_, mutable_cf_options_, vstorage_.get(), &log_buffer_, 107));
+  ASSERT_TRUE(compaction.get() != nullptr);
+  ASSERT_EQ(1U, compaction->num_input_levels());
+  ASSERT_EQ(4U, compaction->num_input_files(0));
+  ASSERT_EQ(CompactionReason::kLevelL0FilesNum,
+            compaction->compaction_reason());
+  ASSERT_EQ(0, compaction->output_level());
 }

 }  // namespace rocksdb
@@ -25,6 +25,111 @@

 namespace rocksdb {
 namespace {
+// A helper class that form universal compactions. The class is used by
+// UniversalCompactionPicker::PickCompaction().
+// The usage is to create the class, and get the compaction object by calling
+// PickCompaction().
+class UniversalCompactionBuilder {
+ public:
+  UniversalCompactionBuilder(const ImmutableCFOptions& ioptions,
+                             const InternalKeyComparator* icmp,
+                             const std::string& cf_name,
+                             const MutableCFOptions& mutable_cf_options,
+                             VersionStorageInfo* vstorage,
+                             UniversalCompactionPicker* picker,
+                             LogBuffer* log_buffer)
+      : ioptions_(ioptions),
+        icmp_(icmp),
+        cf_name_(cf_name),
+        mutable_cf_options_(mutable_cf_options),
+        vstorage_(vstorage),
+        picker_(picker),
+        log_buffer_(log_buffer) {}
+
+  // Form and return the compaction object. The caller owns return object.
+  Compaction* PickCompaction();
+
+ private:
+  struct SortedRun {
+    SortedRun(int _level, FileMetaData* _file, uint64_t _size,
+              uint64_t _compensated_file_size, bool _being_compacted)
+        : level(_level),
+          file(_file),
+          size(_size),
+          compensated_file_size(_compensated_file_size),
+          being_compacted(_being_compacted) {
+      assert(compensated_file_size > 0);
+      assert(level != 0 || file != nullptr);
+    }
+
+    void Dump(char* out_buf, size_t out_buf_size,
+              bool print_path = false) const;
+
+    // sorted_run_count is added into the string to print
+    void DumpSizeInfo(char* out_buf, size_t out_buf_size,
+                      size_t sorted_run_count) const;
+
+    int level;
+    // `file` Will be null for level > 0. For level = 0, the sorted run is
+    // for this file.
+    FileMetaData* file;
+    // For level > 0, `size` and `compensated_file_size` are sum of sizes all
+    // files in the level. `being_compacted` should be the same for all files
+    // in a non-zero level. Use the value here.
+    uint64_t size;
+    uint64_t compensated_file_size;
+    bool being_compacted;
+  };
+
+  // Pick Universal compaction to limit read amplification
+  Compaction* PickCompactionToReduceSortedRuns(
+      unsigned int ratio, unsigned int max_number_of_files_to_compact);
+
+  // Pick Universal compaction to limit space amplification.
+  Compaction* PickCompactionToReduceSizeAmp();
+
+  Compaction* PickDeleteTriggeredCompaction();
+
+  // Form a compaction from the sorted run indicated by start_index to the
+  // oldest sorted run.
+  // The caller is responsible for making sure that those files are not in
+  // compaction.
+  Compaction* PickCompactionToOldest(size_t start_index,
+                                     CompactionReason compaction_reason);
+
+  // Try to pick periodic compaction. The caller should only call it
+  // if there is at least one file marked for periodic compaction.
+  // null will be returned if no such a compaction can be formed
+  // because some files are being compacted.
+  Compaction* PickPeriodicCompaction();
+
+  // Used in universal compaction when the enabled_trivial_move
+  // option is set. Checks whether there are any overlapping files
+  // in the input. Returns true if the input files are non
+  // overlapping.
+  bool IsInputFilesNonOverlapping(Compaction* c);
+
+  const ImmutableCFOptions& ioptions_;
+  const InternalKeyComparator* icmp_;
+  double score_;
+  std::vector<SortedRun> sorted_runs_;
+  const std::string& cf_name_;
+  const MutableCFOptions& mutable_cf_options_;
+  VersionStorageInfo* vstorage_;
+  UniversalCompactionPicker* picker_;
+  LogBuffer* log_buffer_;
+
+  static std::vector<SortedRun> CalculateSortedRuns(
+      const VersionStorageInfo& vstorage, const ImmutableCFOptions& ioptions,
+      const MutableCFOptions& mutable_cf_options);
+
+  // Pick a path ID to place a newly generated file, with its estimated file
+  // size.
+  static uint32_t GetPathId(const ImmutableCFOptions& ioptions,
+                            const MutableCFOptions& mutable_cf_options,
+                            uint64_t file_size);
+};
+
 // Used in universal compaction when trivial move is enabled.
 // This structure is used for the construction of min heap
 // that contains the file meta data, the level of the file
@@ -113,7 +218,7 @@ void GetSmallestLargestSeqno(const std::vector<FileMetaData*>& files,

 // Algorithm that checks to see if there are any overlapping
 // files in the input
-bool UniversalCompactionPicker::IsInputFilesNonOverlapping(Compaction* c) {
+bool UniversalCompactionBuilder::IsInputFilesNonOverlapping(Compaction* c) {
  auto comparator = icmp_->user_comparator();
  int first_iter = 1;

@@ -142,7 +247,8 @@ bool UniversalCompactionPicker::IsInputFilesNonOverlapping(Compaction* c) {

    next.f = nullptr;

-    if (curr.level != 0 && curr.index < c->num_input_files(curr.level) - 1) {
+    if (c->level(curr.level) != 0 &&
+        curr.index < c->num_input_files(curr.level) - 1) {
      next.f = c->input(curr.level, curr.index + 1);
      next.level = curr.level;
      next.index = curr.index + 1;
@@ -161,15 +267,28 @@ bool UniversalCompactionPicker::NeedsCompaction(
  if (vstorage->CompactionScore(kLevel0) >= 1) {
    return true;
  }
+  if (!vstorage->FilesMarkedForPeriodicCompaction().empty()) {
+    return true;
+  }
  if (!vstorage->FilesMarkedForCompaction().empty()) {
    return true;
  }
  return false;
 }

-void UniversalCompactionPicker::SortedRun::Dump(char* out_buf,
-                                                size_t out_buf_size,
-                                                bool print_path) const {
+Compaction* UniversalCompactionPicker::PickCompaction(
+    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
+    VersionStorageInfo* vstorage, LogBuffer* log_buffer,
+    SequenceNumber /* earliest_memtable_seqno */) {
+  UniversalCompactionBuilder builder(ioptions_, icmp_, cf_name,
+                                     mutable_cf_options, vstorage, this,
+                                     log_buffer);
+  return builder.PickCompaction();
+}
+
+void UniversalCompactionBuilder::SortedRun::Dump(char* out_buf,
+                                                 size_t out_buf_size,
+                                                 bool print_path) const {
  if (level == 0) {
    assert(file != nullptr);
    if (file->fd.GetPathId() == 0 || !print_path) {
@@ -185,7 +304,7 @@ void UniversalCompactionPicker::SortedRun::Dump(char* out_buf,
  }
 }

-void UniversalCompactionPicker::SortedRun::DumpSizeInfo(
+void UniversalCompactionBuilder::SortedRun::DumpSizeInfo(
    char* out_buf, size_t out_buf_size, size_t sorted_run_count) const {
  if (level == 0) {
    assert(file != nullptr);
@@ -204,11 +323,11 @@ void UniversalCompactionPicker::SortedRun::DumpSizeInfo(
  }
 }

-std::vector<UniversalCompactionPicker::SortedRun>
-UniversalCompactionPicker::CalculateSortedRuns(
+std::vector<UniversalCompactionBuilder::SortedRun>
+UniversalCompactionBuilder::CalculateSortedRuns(
    const VersionStorageInfo& vstorage, const ImmutableCFOptions& /*ioptions*/,
    const MutableCFOptions& mutable_cf_options) {
-  std::vector<UniversalCompactionPicker::SortedRun> ret;
+  std::vector<UniversalCompactionBuilder::SortedRun> ret;
  for (FileMetaData* f : vstorage.LevelFiles(0)) {
    ret.emplace_back(0, f, f->fd.GetFileSize(), f->compensated_file_size,
                     f->being_compacted);
@@ -231,8 +350,8 @@ UniversalCompactionPicker::CalculateSortedRuns(
        // non-zero level, all the files should share the same being_compacted
        // value.
        // This assumption is only valid when
-        // mutable_cf_options.compaction_options_universal.allow_trivial_move is
-        // false
+        // mutable_cf_options.compaction_options_universal.allow_trivial_move
+        // is false
        assert(is_first || f->being_compacted == being_compacted);
      }
      if (is_first) {
@@ -250,65 +369,68 @@ UniversalCompactionPicker::CalculateSortedRuns(

 // Universal style of compaction. Pick files that are contiguous in
 // time-range to compact.
-Compaction* UniversalCompactionPicker::PickCompaction(
-    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-    VersionStorageInfo* vstorage, LogBuffer* log_buffer) {
+Compaction* UniversalCompactionBuilder::PickCompaction() {
  const int kLevel0 = 0;
-  double score = vstorage->CompactionScore(kLevel0);
-  std::vector<SortedRun> sorted_runs =
-      CalculateSortedRuns(*vstorage, ioptions_, mutable_cf_options);
+  score_ = vstorage_->CompactionScore(kLevel0);
+  sorted_runs_ =
+      CalculateSortedRuns(*vstorage_, ioptions_, mutable_cf_options_);

-  if (sorted_runs.size() == 0 ||
-      (vstorage->FilesMarkedForCompaction().empty() &&
-       sorted_runs.size() < (unsigned int)mutable_cf_options
-                                .level0_file_num_compaction_trigger)) {
-    ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: nothing to do\n",
-                     cf_name.c_str());
-    TEST_SYNC_POINT_CALLBACK("UniversalCompactionPicker::PickCompaction:Return",
-                             nullptr);
+  if (sorted_runs_.size() == 0 ||
+      (vstorage_->FilesMarkedForPeriodicCompaction().empty() &&
+       vstorage_->FilesMarkedForCompaction().empty() &&
+       sorted_runs_.size() < (unsigned int)mutable_cf_options_
+                                 .level0_file_num_compaction_trigger)) {
+    ROCKS_LOG_BUFFER(log_buffer_, "[%s] Universal: nothing to do\n",
+                     cf_name_.c_str());
+    TEST_SYNC_POINT_CALLBACK(
+        "UniversalCompactionBuilder::PickCompaction:Return", nullptr);
    return nullptr;
  }
  VersionStorageInfo::LevelSummaryStorage tmp;
  ROCKS_LOG_BUFFER_MAX_SZ(
-      log_buffer, 3072,
+      log_buffer_, 3072,
      "[%s] Universal: sorted runs files(%" ROCKSDB_PRIszt "): %s\n",
-      cf_name.c_str(), sorted_runs.size(), vstorage->LevelSummary(&tmp));
+      cf_name_.c_str(), sorted_runs_.size(), vstorage_->LevelSummary(&tmp));

-  // Check for size amplification first.
  Compaction* c = nullptr;
-  if (sorted_runs.size() >=
-      static_cast<size_t>(
-          mutable_cf_options.level0_file_num_compaction_trigger)) {
-    if ((c = PickCompactionToReduceSizeAmp(cf_name, mutable_cf_options,
-                                           vstorage, score, sorted_runs,
-                                           log_buffer)) != nullptr) {
-      ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: compacting for size amp\n",
-                       cf_name.c_str());
+  // Periodic compaction has higher priority than other type of compaction
+  // because it's a hard requirement.
+  if (!vstorage_->FilesMarkedForPeriodicCompaction().empty()) {
+    // Always need to do a full compaction for periodic compaction.
+    c = PickPeriodicCompaction();
+  }
+
+  // Check for size amplification.
+  if (c == nullptr &&
+      sorted_runs_.size() >=
+          static_cast<size_t>(
+              mutable_cf_options_.level0_file_num_compaction_trigger)) {
+    if ((c = PickCompactionToReduceSizeAmp()) != nullptr) {
+      ROCKS_LOG_BUFFER(log_buffer_, "[%s] Universal: compacting for size amp\n",
+                       cf_name_.c_str());
    } else {
      // Size amplification is within limits. Try reducing read
      // amplification while maintaining file size ratios.
      unsigned int ratio =
-          mutable_cf_options.compaction_options_universal.size_ratio;
+          mutable_cf_options_.compaction_options_universal.size_ratio;

-      if ((c = PickCompactionToReduceSortedRuns(
-               cf_name, mutable_cf_options, vstorage, score, ratio, UINT_MAX,
-               sorted_runs, log_buffer)) != nullptr) {
-        ROCKS_LOG_BUFFER(log_buffer,
+      if ((c = PickCompactionToReduceSortedRuns(ratio, UINT_MAX)) != nullptr) {
+        ROCKS_LOG_BUFFER(log_buffer_,
                         "[%s] Universal: compacting for size ratio\n",
-                         cf_name.c_str());
+                         cf_name_.c_str());
      } else {
        // Size amplification and file size ratios are within configured limits.
        // If max read amplification is exceeding configured limits, then force
        // compaction without looking at filesize ratios and try to reduce
        // the number of files to fewer than level0_file_num_compaction_trigger.
        // This is guaranteed by NeedsCompaction()
-        assert(sorted_runs.size() >=
+        assert(sorted_runs_.size() >=
               static_cast<size_t>(
-                   mutable_cf_options.level0_file_num_compaction_trigger));
+                   mutable_cf_options_.level0_file_num_compaction_trigger));
        // Get the total number of sorted runs that are not being compacted
        int num_sr_not_compacted = 0;
-        for (size_t i = 0; i < sorted_runs.size(); i++) {
-          if (sorted_runs[i].being_compacted == false) {
+        for (size_t i = 0; i < sorted_runs_.size(); i++) {
+          if (sorted_runs_[i].being_compacted == false) {
            num_sr_not_compacted++;
          }
        }
@@ -316,16 +438,15 @@ Compaction* UniversalCompactionPicker::PickCompaction(
        // The number of sorted runs that are not being compacted is greater
        // than the maximum allowed number of sorted runs
        if (num_sr_not_compacted >
-            mutable_cf_options.level0_file_num_compaction_trigger) {
+            mutable_cf_options_.level0_file_num_compaction_trigger) {
          unsigned int num_files =
              num_sr_not_compacted -
-              mutable_cf_options.level0_file_num_compaction_trigger + 1;
-          if ((c = PickCompactionToReduceSortedRuns(
-                   cf_name, mutable_cf_options, vstorage, score, UINT_MAX,
-                   num_files, sorted_runs, log_buffer)) != nullptr) {
-            ROCKS_LOG_BUFFER(log_buffer,
+              mutable_cf_options_.level0_file_num_compaction_trigger + 1;
+          if ((c = PickCompactionToReduceSortedRuns(UINT_MAX, num_files)) !=
+              nullptr) {
+            ROCKS_LOG_BUFFER(log_buffer_,
                             "[%s] Universal: compacting for file num -- %u\n",
-                             cf_name.c_str(), num_files);
+                             cf_name_.c_str(), num_files);
          }
        }
      }
@@ -333,23 +454,22 @@ Compaction* UniversalCompactionPicker::PickCompaction(
  }

  if (c == nullptr) {
-    if ((c = PickDeleteTriggeredCompaction(cf_name, mutable_cf_options,
-                                           vstorage, score, sorted_runs,
-                                           log_buffer)) != nullptr) {
-      ROCKS_LOG_BUFFER(log_buffer,
+    if ((c = PickDeleteTriggeredCompaction()) != nullptr) {
+      ROCKS_LOG_BUFFER(log_buffer_,
                       "[%s] Universal: delete triggered compaction\n",
-                       cf_name.c_str());
+                       cf_name_.c_str());
    }
  }

  if (c == nullptr) {
-    TEST_SYNC_POINT_CALLBACK("UniversalCompactionPicker::PickCompaction:Return",
-                             nullptr);
+    TEST_SYNC_POINT_CALLBACK(
+        "UniversalCompactionBuilder::PickCompaction:Return", nullptr);
    return nullptr;
  }

-  if (mutable_cf_options.compaction_options_universal.allow_trivial_move ==
-      true) {
+  if (mutable_cf_options_.compaction_options_universal.allow_trivial_move ==
+          true &&
+      c->compaction_reason() != CompactionReason::kPeriodicCompaction) {
    c->set_is_trivial_move(IsInputFilesNonOverlapping(c));
  }

@@ -394,15 +514,15 @@ Compaction* UniversalCompactionPicker::PickCompaction(
  RecordInHistogram(ioptions_.statistics, NUM_FILES_IN_SINGLE_COMPACTION,
                    c->inputs(0)->size());

-  RegisterCompaction(c);
-  vstorage->ComputeCompactionScore(ioptions_, mutable_cf_options);
+  picker_->RegisterCompaction(c);
+  vstorage_->ComputeCompactionScore(ioptions_, mutable_cf_options_);

-  TEST_SYNC_POINT_CALLBACK("UniversalCompactionPicker::PickCompaction:Return",
+  TEST_SYNC_POINT_CALLBACK("UniversalCompactionBuilder::PickCompaction:Return",
                           c);
  return c;
 }

-uint32_t UniversalCompactionPicker::GetPathId(
+uint32_t UniversalCompactionBuilder::GetPathId(
    const ImmutableCFOptions& ioptions,
    const MutableCFOptions& mutable_cf_options, uint64_t file_size) {
  // Two conditions need to be satisfied:
@@ -440,15 +560,12 @@ uint32_t UniversalCompactionPicker::GetPathId(
 // Consider compaction files based on their size differences with
 // the next file in time order.
 //
-Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
-    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-    VersionStorageInfo* vstorage, double score, unsigned int ratio,
-    unsigned int max_number_of_files_to_compact,
-    const std::vector<SortedRun>& sorted_runs, LogBuffer* log_buffer) {
+Compaction* UniversalCompactionBuilder::PickCompactionToReduceSortedRuns(
+    unsigned int ratio, unsigned int max_number_of_files_to_compact) {
  unsigned int min_merge_width =
-      mutable_cf_options.compaction_options_universal.min_merge_width;
+      mutable_cf_options_.compaction_options_universal.min_merge_width;
  unsigned int max_merge_width =
-      mutable_cf_options.compaction_options_universal.max_merge_width;
+      mutable_cf_options_.compaction_options_universal.max_merge_width;

  const SortedRun* sr = nullptr;
  bool done = false;
@@ -462,16 +579,16 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
  // Caller checks the size before executing this function. This invariant is
  // important because otherwise we may have a possible integer underflow when
  // dealing with unsigned types.
-  assert(sorted_runs.size() > 0);
+  assert(sorted_runs_.size() > 0);

  // Considers a candidate file only if it is smaller than the
  // total size accumulated so far.
-  for (size_t loop = 0; loop < sorted_runs.size(); loop++) {
+  for (size_t loop = 0; loop < sorted_runs_.size(); loop++) {
    candidate_count = 0;

    // Skip files that are already being compacted
-    for (sr = nullptr; loop < sorted_runs.size(); loop++) {
-      sr = &sorted_runs[loop];
+    for (sr = nullptr; loop < sorted_runs_.size(); loop++) {
+      sr = &sorted_runs_[loop];

      if (!sr->being_compacted) {
        candidate_count = 1;
@@ -479,10 +596,10 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
      }
      char file_num_buf[kFormatFileNumberBufSize];
      sr->Dump(file_num_buf, sizeof(file_num_buf));
-      ROCKS_LOG_BUFFER(log_buffer,
+      ROCKS_LOG_BUFFER(log_buffer_,
                       "[%s] Universal: %s"
                       "[%d] being compacted, skipping",
-                       cf_name.c_str(), file_num_buf, loop);
+                       cf_name_.c_str(), file_num_buf, loop);

      sr = nullptr;
    }
@@ -493,15 +610,16 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
    if (sr != nullptr) {
      char file_num_buf[kFormatFileNumberBufSize];
      sr->Dump(file_num_buf, sizeof(file_num_buf), true);
-      ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: Possible candidate %s[%d].",
-                       cf_name.c_str(), file_num_buf, loop);
+      ROCKS_LOG_BUFFER(log_buffer_,
+                       "[%s] Universal: Possible candidate %s[%d].",
+                       cf_name_.c_str(), file_num_buf, loop);
    }

    // Check if the succeeding files need compaction.
    for (size_t i = loop + 1;
-         candidate_count < max_files_to_compact && i < sorted_runs.size();
+         candidate_count < max_files_to_compact && i < sorted_runs_.size();
         i++) {
-      const SortedRun* succeeding_sr = &sorted_runs[i];
+      const SortedRun* succeeding_sr = &sorted_runs_[i];
      if (succeeding_sr->being_compacted) {
        break;
      }
@@ -515,7 +633,7 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
      if (sz < static_cast<double>(succeeding_sr->size)) {
        break;
      }
-      if (mutable_cf_options.compaction_options_universal.stop_style ==
+      if (mutable_cf_options_.compaction_options_universal.stop_style ==
          kCompactionStopStyleSimilarSize) {
        // Similar-size stopping rule: also check the last picked file isn't
        // far larger than the next candidate file.
@@ -541,12 +659,12 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
      break;
    } else {
      for (size_t i = loop;
-           i < loop + candidate_count && i < sorted_runs.size(); i++) {
-        const SortedRun* skipping_sr = &sorted_runs[i];
+           i < loop + candidate_count && i < sorted_runs_.size(); i++) {
+        const SortedRun* skipping_sr = &sorted_runs_[i];
        char file_num_buf[256];
        skipping_sr->DumpSizeInfo(file_num_buf, sizeof(file_num_buf), loop);
-        ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: Skipping %s",
-                         cf_name.c_str(), file_num_buf);
+        ROCKS_LOG_BUFFER(log_buffer_, "[%s] Universal: Skipping %s",
+                         cf_name_.c_str(), file_num_buf);
      }
    }
  }
@@ -558,16 +676,16 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
  // size ratio of compression.
  bool enable_compression = true;
  int ratio_to_compress =
-      mutable_cf_options.compaction_options_universal.compression_size_percent;
+      mutable_cf_options_.compaction_options_universal.compression_size_percent;
  if (ratio_to_compress >= 0) {
    uint64_t total_size = 0;
-    for (auto& sorted_run : sorted_runs) {
+    for (auto& sorted_run : sorted_runs_) {
      total_size += sorted_run.compensated_file_size;
    }

    uint64_t older_file_size = 0;
-    for (size_t i = sorted_runs.size() - 1; i >= first_index_after; i--) {
-      older_file_size += sorted_runs[i].size;
+    for (size_t i = sorted_runs_.size() - 1; i >= first_index_after; i--) {
+      older_file_size += sorted_runs_[i].size;
      if (older_file_size * 100L >= total_size * (long)ratio_to_compress) {
        enable_compression = false;
        break;
@@ -577,46 +695,46 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(

  uint64_t estimated_total_size = 0;
  for (unsigned int i = 0; i < first_index_after; i++) {
-    estimated_total_size += sorted_runs[i].size;
+    estimated_total_size += sorted_runs_[i].size;
  }
  uint32_t path_id =
-      GetPathId(ioptions_, mutable_cf_options, estimated_total_size);
-  int start_level = sorted_runs[start_index].level;
+      GetPathId(ioptions_, mutable_cf_options_, estimated_total_size);
+  int start_level = sorted_runs_[start_index].level;
  int output_level;
-  if (first_index_after == sorted_runs.size()) {
-    output_level = vstorage->num_levels() - 1;
-  } else if (sorted_runs[first_index_after].level == 0) {
+  if (first_index_after == sorted_runs_.size()) {
+    output_level = vstorage_->num_levels() - 1;
+  } else if (sorted_runs_[first_index_after].level == 0) {
    output_level = 0;
  } else {
-    output_level = sorted_runs[first_index_after].level - 1;
+    output_level = sorted_runs_[first_index_after].level - 1;
  }

  // last level is reserved for the files ingested behind
  if (ioptions_.allow_ingest_behind &&
-      (output_level == vstorage->num_levels() - 1)) {
+      (output_level == vstorage_->num_levels() - 1)) {
    assert(output_level > 1);
    output_level--;
  }

-  std::vector<CompactionInputFiles> inputs(vstorage->num_levels());
+  std::vector<CompactionInputFiles> inputs(vstorage_->num_levels());
  for (size_t i = 0; i < inputs.size(); ++i) {
    inputs[i].level = start_level + static_cast<int>(i);
  }
  for (size_t i = start_index; i < first_index_after; i++) {
-    auto& picking_sr = sorted_runs[i];
+    auto& picking_sr = sorted_runs_[i];
    if (picking_sr.level == 0) {
      FileMetaData* picking_file = picking_sr.file;
      inputs[0].files.push_back(picking_file);
    } else {
      auto& files = inputs[picking_sr.level - start_level].files;
-      for (auto* f : vstorage->LevelFiles(picking_sr.level)) {
+      for (auto* f : vstorage_->LevelFiles(picking_sr.level)) {
        files.push_back(f);
      }
    }
    char file_num_buf[256];
    picking_sr.DumpSizeInfo(file_num_buf, sizeof(file_num_buf), i);
-    ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: Picking %s", cf_name.c_str(),
-                     file_num_buf);
+    ROCKS_LOG_BUFFER(log_buffer_, "[%s] Universal: Picking %s",
+                     cf_name_.c_str(), file_num_buf);
  }

  CompactionReason compaction_reason;
@@ -626,16 +744,17 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
    compaction_reason = CompactionReason::kUniversalSortedRunNum;
  }
  return new Compaction(
-      vstorage, ioptions_, mutable_cf_options, std::move(inputs), output_level,
-      MaxFileSizeForLevel(mutable_cf_options, output_level,
+      vstorage_, ioptions_, mutable_cf_options_, std::move(inputs),
+      output_level,
+      MaxFileSizeForLevel(mutable_cf_options_, output_level,
                          kCompactionStyleUniversal),
      LLONG_MAX, path_id,
-      GetCompressionType(ioptions_, vstorage, mutable_cf_options, start_level,
+      GetCompressionType(ioptions_, vstorage_, mutable_cf_options_, start_level,
                         1, enable_compression),
-      GetCompressionOptions(ioptions_, vstorage, start_level,
+      GetCompressionOptions(ioptions_, vstorage_, start_level,
                            enable_compression),
      /* max_subcompactions */ 0, /* grandparents */ {}, /* is manual */ false,
-      score, false /* deletion_compaction */, compaction_reason);
+      score_, false /* deletion_compaction */, compaction_reason);
 }

 // Look at overall size amplification. If size amplification
@@ -644,12 +763,9 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSortedRuns(
 // base file (overrides configured values of file-size ratios,
 // min_merge_width and max_merge_width).
 //
-Compaction* UniversalCompactionPicker::PickCompactionToReduceSizeAmp(
-    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-    VersionStorageInfo* vstorage, double score,
-    const std::vector<SortedRun>& sorted_runs, LogBuffer* log_buffer) {
+Compaction* UniversalCompactionBuilder::PickCompactionToReduceSizeAmp() {
  // percentage flexibility while reducing size amplification
-  uint64_t ratio = mutable_cf_options.compaction_options_universal
+  uint64_t ratio = mutable_cf_options_.compaction_options_universal
                       .max_size_amplification_percent;

  unsigned int candidate_count = 0;
@@ -657,21 +773,23 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSizeAmp(
  size_t start_index = 0;
  const SortedRun* sr = nullptr;

-  if (sorted_runs.back().being_compacted) {
+  assert(!sorted_runs_.empty());
+  if (sorted_runs_.back().being_compacted) {
    return nullptr;
  }

  // Skip files that are already being compacted
-  for (size_t loop = 0; loop < sorted_runs.size() - 1; loop++) {
-    sr = &sorted_runs[loop];
+  for (size_t loop = 0; loop < sorted_runs_.size() - 1; loop++) {
+    sr = &sorted_runs_[loop];
    if (!sr->being_compacted) {
      start_index = loop;  // Consider this as the first candidate.
      break;
    }
    char file_num_buf[kFormatFileNumberBufSize];
    sr->Dump(file_num_buf, sizeof(file_num_buf), true);
-    ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: skipping %s[%d] compacted %s",
-                     cf_name.c_str(), file_num_buf, loop,
+    ROCKS_LOG_BUFFER(log_buffer_,
+                     "[%s] Universal: skipping %s[%d] compacted %s",
+                     cf_name_.c_str(), file_num_buf, loop,
                     " cannot be a candidate to reduce size amp.\n");
    sr = nullptr;
  }
@@ -683,20 +801,20 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSizeAmp(
    char file_num_buf[kFormatFileNumberBufSize];
    sr->Dump(file_num_buf, sizeof(file_num_buf), true);
    ROCKS_LOG_BUFFER(
-        log_buffer,
+        log_buffer_,
        "[%s] Universal: First candidate %s[%" ROCKSDB_PRIszt "] %s",
-        cf_name.c_str(), file_num_buf, start_index, " to reduce size amp.\n");
+        cf_name_.c_str(), file_num_buf, start_index, " to reduce size amp.\n");
  }

  // keep adding up all the remaining files
-  for (size_t loop = start_index; loop < sorted_runs.size() - 1; loop++) {
-    sr = &sorted_runs[loop];
+  for (size_t loop = start_index; loop < sorted_runs_.size() - 1; loop++) {
+    sr = &sorted_runs_[loop];
    if (sr->being_compacted) {
      char file_num_buf[kFormatFileNumberBufSize];
      sr->Dump(file_num_buf, sizeof(file_num_buf), true);
      ROCKS_LOG_BUFFER(
-          log_buffer, "[%s] Universal: Possible candidate %s[%d] %s",
-          cf_name.c_str(), file_num_buf, start_index,
+          log_buffer_, "[%s] Universal: Possible candidate %s[%d] %s",
+          cf_name_.c_str(), file_num_buf, start_index,
          " is already being compacted. No size amp reduction possible.\n");
      return nullptr;
    }
@@ -708,88 +826,35 @@ Compaction* UniversalCompactionPicker::PickCompactionToReduceSizeAmp(
  }

  // size of earliest file
-  uint64_t earliest_file_size = sorted_runs.back().size;
+  uint64_t earliest_file_size = sorted_runs_.back().size;

  // size amplification = percentage of additional size
  if (candidate_size * 100 < ratio * earliest_file_size) {
    ROCKS_LOG_BUFFER(
-        log_buffer,
+        log_buffer_,
        "[%s] Universal: size amp not needed. newer-files-total-size %" PRIu64
        " earliest-file-size %" PRIu64,
-        cf_name.c_str(), candidate_size, earliest_file_size);
+        cf_name_.c_str(), candidate_size, earliest_file_size);
    return nullptr;
  } else {
    ROCKS_LOG_BUFFER(
-        log_buffer,
+        log_buffer_,
        "[%s] Universal: size amp needed. newer-files-total-size %" PRIu64
        " earliest-file-size %" PRIu64,
-        cf_name.c_str(), candidate_size, earliest_file_size);
+        cf_name_.c_str(), candidate_size, earliest_file_size);
  }
-  assert(start_index < sorted_runs.size() - 1);
-
-  // Estimate total file size
-  uint64_t estimated_total_size = 0;
-  for (size_t loop = start_index; loop < sorted_runs.size(); loop++) {
-    estimated_total_size += sorted_runs[loop].size;
-  }
-  uint32_t path_id =
-      GetPathId(ioptions_, mutable_cf_options, estimated_total_size);
-  int start_level = sorted_runs[start_index].level;
-
-  std::vector<CompactionInputFiles> inputs(vstorage->num_levels());
-  for (size_t i = 0; i < inputs.size(); ++i) {
-    inputs[i].level = start_level + static_cast<int>(i);
-  }
-  // We always compact all the files, so always compress.
-  for (size_t loop = start_index; loop < sorted_runs.size(); loop++) {
-    auto& picking_sr = sorted_runs[loop];
-    if (picking_sr.level == 0) {
-      FileMetaData* f = picking_sr.file;
-      inputs[0].files.push_back(f);
-    } else {
-      auto& files = inputs[picking_sr.level - start_level].files;
-      for (auto* f : vstorage->LevelFiles(picking_sr.level)) {
-        files.push_back(f);
-      }
-    }
-    char file_num_buf[256];
-    picking_sr.DumpSizeInfo(file_num_buf, sizeof(file_num_buf), loop);
-    ROCKS_LOG_BUFFER(log_buffer, "[%s] Universal: size amp picking %s",
-                     cf_name.c_str(), file_num_buf);
-  }
-
-  // output files at the bottom most level, unless it's reserved
-  int output_level = vstorage->num_levels() - 1;
-  // last level is reserved for the files ingested behind
-  if (ioptions_.allow_ingest_behind) {
-    assert(output_level > 1);
-    output_level--;
-  }
-
-  return new Compaction(
-      vstorage, ioptions_, mutable_cf_options, std::move(inputs), output_level,
-      MaxFileSizeForLevel(mutable_cf_options, output_level,
-                          kCompactionStyleUniversal),
-      /* max_grandparent_overlap_bytes */ LLONG_MAX, path_id,
-      GetCompressionType(ioptions_, vstorage, mutable_cf_options, output_level,
-                         1),
-      GetCompressionOptions(ioptions_, vstorage, output_level),
-      /* max_subcompactions */ 0, /* grandparents */ {}, /* is manual */ false,
-      score, false /* deletion_compaction */,
-      CompactionReason::kUniversalSizeAmplification);
+  return PickCompactionToOldest(start_index,
+                                CompactionReason::kUniversalSizeAmplification);
 }

 // Pick files marked for compaction. Typically, files are marked by
 // CompactOnDeleteCollector due to the presence of tombstones.
-Compaction* UniversalCompactionPicker::PickDeleteTriggeredCompaction(
-    const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-    VersionStorageInfo* vstorage, double score,
-    const std::vector<SortedRun>& /*sorted_runs*/, LogBuffer* /*log_buffer*/) {
+Compaction* UniversalCompactionBuilder::PickDeleteTriggeredCompaction() {
  CompactionInputFiles start_level_inputs;
  int output_level;
  std::vector<CompactionInputFiles> inputs;

-  if (vstorage->num_levels() == 1) {
+  if (vstorage_->num_levels() == 1) {
    // This is single level universal. Since we're basically trying to reclaim
    // space by processing files marked for compaction due to high tombstone
    // density, let's do the same thing as compaction to reduce size amp which
@@ -799,7 +864,7 @@ Compaction* UniversalCompactionPicker::PickDeleteTriggeredCompaction(
    start_level_inputs.level = 0;
    start_level_inputs.files.clear();
    output_level = 0;
-    for (FileMetaData* f : vstorage->LevelFiles(0)) {
+    for (FileMetaData* f : vstorage_->LevelFiles(0)) {
      if (f->marked_for_compaction) {
        compact = true;
      }
@@ -818,24 +883,24 @@ Compaction* UniversalCompactionPicker::PickDeleteTriggeredCompaction(
    // For multi-level universal, the strategy is to make this look more like
    // leveled. We pick one of the files marked for compaction and compact with
    // overlapping files in the adjacent level.
-    PickFilesMarkedForCompaction(cf_name, vstorage, &start_level, &output_level,
-                                 &start_level_inputs);
+    picker_->PickFilesMarkedForCompaction(cf_name_, vstorage_, &start_level,
+                                          &output_level, &start_level_inputs);
    if (start_level_inputs.empty()) {
      return nullptr;
    }

    // Pick the first non-empty level after the start_level
-    for (output_level = start_level + 1; output_level < vstorage->num_levels();
+    for (output_level = start_level + 1; output_level < vstorage_->num_levels();
         output_level++) {
-      if (vstorage->NumLevelFiles(output_level) != 0) {
+      if (vstorage_->NumLevelFiles(output_level) != 0) {
        break;
      }
    }

    // If all higher levels are empty, pick the highest level as output level
-    if (output_level == vstorage->num_levels()) {
+    if (output_level == vstorage_->num_levels()) {
      if (start_level == 0) {
-        output_level = vstorage->num_levels() - 1;
+        output_level = vstorage_->num_levels() - 1;
      } else {
        // If start level is non-zero and all higher levels are empty, this
        // compaction will translate into a trivial move. Since the idea is
@@ -845,15 +910,15 @@ Compaction* UniversalCompactionPicker::PickDeleteTriggeredCompaction(
      }
    }
    if (ioptions_.allow_ingest_behind &&
-        output_level == vstorage->num_levels() - 1) {
+        output_level == vstorage_->num_levels() - 1) {
      assert(output_level > 1);
      output_level--;
    }

    if (output_level != 0) {
      if (start_level == 0) {
-        if (!GetOverlappingL0Files(vstorage, &start_level_inputs, output_level,
-                                   nullptr)) {
+        if (!picker_->GetOverlappingL0Files(vstorage_, &start_level_inputs,
+                                            output_level, nullptr)) {
          return nullptr;
        }
      }
@@ -862,16 +927,16 @@ Compaction* UniversalCompactionPicker::PickDeleteTriggeredCompaction(
      int parent_index = -1;

      output_level_inputs.level = output_level;
-      if (!SetupOtherInputs(cf_name, mutable_cf_options, vstorage,
-                            &start_level_inputs, &output_level_inputs,
-                            &parent_index, -1)) {
+      if (!picker_->SetupOtherInputs(cf_name_, mutable_cf_options_, vstorage_,
+                                     &start_level_inputs, &output_level_inputs,
+                                     &parent_index, -1)) {
        return nullptr;
      }
      inputs.push_back(start_level_inputs);
      if (!output_level_inputs.empty()) {
        inputs.push_back(output_level_inputs);
      }
-      if (FilesRangeOverlapWithCompaction(inputs, output_level)) {
+      if (picker_->FilesRangeOverlapWithCompaction(inputs, output_level)) {
        return nullptr;
      }
    } else {
@@ -881,23 +946,160 @@ Compaction* UniversalCompactionPicker::PickDeleteTriggeredCompaction(

  uint64_t estimated_total_size = 0;
  // Use size of the output level as estimated file size
-  for (FileMetaData* f : vstorage->LevelFiles(output_level)) {
+  for (FileMetaData* f : vstorage_->LevelFiles(output_level)) {
    estimated_total_size += f->fd.GetFileSize();
  }
  uint32_t path_id =
-      GetPathId(ioptions_, mutable_cf_options, estimated_total_size);
+      GetPathId(ioptions_, mutable_cf_options_, estimated_total_size);
  return new Compaction(
-      vstorage, ioptions_, mutable_cf_options, std::move(inputs), output_level,
-      MaxFileSizeForLevel(mutable_cf_options, output_level,
+      vstorage_, ioptions_, mutable_cf_options_, std::move(inputs),
+      output_level,
+      MaxFileSizeForLevel(mutable_cf_options_, output_level,
                          kCompactionStyleUniversal),
      /* max_grandparent_overlap_bytes */ LLONG_MAX, path_id,
-      GetCompressionType(ioptions_, vstorage, mutable_cf_options, output_level,
-                         1),
-      GetCompressionOptions(ioptions_, vstorage, output_level),
+      GetCompressionType(ioptions_, vstorage_, mutable_cf_options_,
+                         output_level, 1),
+      GetCompressionOptions(ioptions_, vstorage_, output_level),
      /* max_subcompactions */ 0, /* grandparents */ {}, /* is manual */ true,
-      score, false /* deletion_compaction */,
+      score_, false /* deletion_compaction */,
      CompactionReason::kFilesMarkedForCompaction);
 }
+
+Compaction* UniversalCompactionBuilder::PickCompactionToOldest(
+    size_t start_index, CompactionReason compaction_reason) {
+  assert(start_index < sorted_runs_.size());
+
+  // Estimate total file size
+  uint64_t estimated_total_size = 0;
+  for (size_t loop = start_index; loop < sorted_runs_.size(); loop++) {
+    estimated_total_size += sorted_runs_[loop].size;
+  }
+  uint32_t path_id =
+      GetPathId(ioptions_, mutable_cf_options_, estimated_total_size);
+  int start_level = sorted_runs_[start_index].level;
+
+  std::vector<CompactionInputFiles> inputs(vstorage_->num_levels());
+  for (size_t i = 0; i < inputs.size(); ++i) {
+    inputs[i].level = start_level + static_cast<int>(i);
+  }
+  for (size_t loop = start_index; loop < sorted_runs_.size(); loop++) {
+    auto& picking_sr = sorted_runs_[loop];
+    if (picking_sr.level == 0) {
+      FileMetaData* f = picking_sr.file;
+      inputs[0].files.push_back(f);
+    } else {
+      auto& files = inputs[picking_sr.level - start_level].files;
+      for (auto* f : vstorage_->LevelFiles(picking_sr.level)) {
+        files.push_back(f);
+      }
+    }
+    std::string comp_reason_print_string;
+    if (compaction_reason == CompactionReason::kPeriodicCompaction) {
+      comp_reason_print_string = "periodic compaction";
+    } else if (compaction_reason ==
+               CompactionReason::kUniversalSizeAmplification) {
+      comp_reason_print_string = "size amp";
+    } else {
+      assert(false);
+    }
+
+    char file_num_buf[256];
+    picking_sr.DumpSizeInfo(file_num_buf, sizeof(file_num_buf), loop);
+    ROCKS_LOG_BUFFER(log_buffer_, "[%s] Universal: %s picking %s",
+                     cf_name_.c_str(), comp_reason_print_string.c_str(),
+                     file_num_buf);
+  }
+
+  // output files at the bottom most level, unless it's reserved
+  int output_level = vstorage_->num_levels() - 1;
+  // last level is reserved for the files ingested behind
+  if (ioptions_.allow_ingest_behind) {
+    assert(output_level > 1);
+    output_level--;
+  }
+
+  // We never check size for
+  // compaction_options_universal.compression_size_percent,
+  // because we always compact all the files, so always compress.
+  return new Compaction(
+      vstorage_, ioptions_, mutable_cf_options_, std::move(inputs),
+      output_level,
+      MaxFileSizeForLevel(mutable_cf_options_, output_level,
+                          kCompactionStyleUniversal),
+      LLONG_MAX, path_id,
+      GetCompressionType(ioptions_, vstorage_, mutable_cf_options_, start_level,
+                         1, true /* enable_compression */),
+      GetCompressionOptions(ioptions_, vstorage_, start_level,
+                            true /* enable_compression */),
+      /* max_subcompactions */ 0, /* grandparents */ {}, /* is manual */ false,
+      score_, false /* deletion_compaction */, compaction_reason);
+}
+
+Compaction* UniversalCompactionBuilder::PickPeriodicCompaction() {
+  ROCKS_LOG_BUFFER(log_buffer_, "[%s] Universal: Periodic Compaction",
+                   cf_name_.c_str());
+
+  // In universal compaction, sorted runs contain older data are almost always
+  // generated earlier too. To simplify the problem, we just try to trigger
+  // a full compaction. We start from the oldest sorted run and include
+  // all sorted runs, until we hit a sorted already being compacted.
+  // Since usually the largest (which is usually the oldest) sorted run is
+  // included anyway, doing a full compaction won't increase write
+  // amplification much.
+
+  // Get some information from marked files to check whether a file is
+  // included in the compaction.
+
+  size_t start_index = sorted_runs_.size();
+  while (start_index > 0 && !sorted_runs_[start_index - 1].being_compacted) {
+    start_index--;
+  }
+  if (start_index == sorted_runs_.size()) {
+    return nullptr;
+  }
+
+  // There is a rare corner case where we can't pick up all the files
+  // because some files are being compacted and we end up with picking files
+  // but none of them need periodic compaction. Unless we simply recompact
+  // the last sorted run (either the last level or last L0 file), we would just
+  // execute the compaction, in order to simplify  the logic.
+  if (start_index == sorted_runs_.size() - 1) {
+    bool included_file_marked = false;
+    int start_level = sorted_runs_[start_index].level;
+    FileMetaData* start_file = sorted_runs_[start_index].file;
+    for (const std::pair<int, FileMetaData*>& level_file_pair :
+         vstorage_->FilesMarkedForPeriodicCompaction()) {
+      if (start_level != 0) {
+        // Last sorted run is a level
+        if (start_level == level_file_pair.first) {
+          included_file_marked = true;
+          break;
+        }
+      } else {
+        // Last sorted run is a L0 file.
+        if (start_file == level_file_pair.second) {
+          included_file_marked = true;
+          break;
+        }
+      }
+    }
+    if (!included_file_marked) {
+      ROCKS_LOG_BUFFER(log_buffer_,
+                       "[%s] Universal: Cannot form a compaction covering file "
+                       "marked for periodic compaction",
+                       cf_name_.c_str());
+      return nullptr;
+    }
+  }
+
+  Compaction* c = PickCompactionToOldest(start_index,
+                                         CompactionReason::kPeriodicCompaction);
+
+  TEST_SYNC_POINT_CALLBACK(
+      "UniversalCompactionPicker::PickPeriodicCompaction:Return", c);
+
+  return c;
+}
 }  // namespace rocksdb

 #endif  // !ROCKSDB_LITE
@@ -18,81 +18,14 @@ class UniversalCompactionPicker : public CompactionPicker {
  UniversalCompactionPicker(const ImmutableCFOptions& ioptions,
                            const InternalKeyComparator* icmp)
      : CompactionPicker(ioptions, icmp) {}
-  virtual Compaction* PickCompaction(const std::string& cf_name,
-                                     const MutableCFOptions& mutable_cf_options,
-                                     VersionStorageInfo* vstorage,
-                                     LogBuffer* log_buffer) override;
-
+  virtual Compaction* PickCompaction(
+      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
+      VersionStorageInfo* vstorage, LogBuffer* log_buffer,
+      SequenceNumber earliest_memtable_seqno = kMaxSequenceNumber) override;
  virtual int MaxOutputLevel() const override { return NumberLevels() - 1; }

  virtual bool NeedsCompaction(
      const VersionStorageInfo* vstorage) const override;
-
- private:
-  struct SortedRun {
-    SortedRun(int _level, FileMetaData* _file, uint64_t _size,
-              uint64_t _compensated_file_size, bool _being_compacted)
-        : level(_level),
-          file(_file),
-          size(_size),
-          compensated_file_size(_compensated_file_size),
-          being_compacted(_being_compacted) {
-      assert(compensated_file_size > 0);
-      assert(level != 0 || file != nullptr);
-    }
-
-    void Dump(char* out_buf, size_t out_buf_size,
-              bool print_path = false) const;
-
-    // sorted_run_count is added into the string to print
-    void DumpSizeInfo(char* out_buf, size_t out_buf_size,
-                      size_t sorted_run_count) const;
-
-    int level;
-    // `file` Will be null for level > 0. For level = 0, the sorted run is
-    // for this file.
-    FileMetaData* file;
-    // For level > 0, `size` and `compensated_file_size` are sum of sizes all
-    // files in the level. `being_compacted` should be the same for all files
-    // in a non-zero level. Use the value here.
-    uint64_t size;
-    uint64_t compensated_file_size;
-    bool being_compacted;
-  };
-
-  // Pick Universal compaction to limit read amplification
-  Compaction* PickCompactionToReduceSortedRuns(
-      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-      VersionStorageInfo* vstorage, double score, unsigned int ratio,
-      unsigned int num_files, const std::vector<SortedRun>& sorted_runs,
-      LogBuffer* log_buffer);
-
-  // Pick Universal compaction to limit space amplification.
-  Compaction* PickCompactionToReduceSizeAmp(
-      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-      VersionStorageInfo* vstorage, double score,
-      const std::vector<SortedRun>& sorted_runs, LogBuffer* log_buffer);
-
-  Compaction* PickDeleteTriggeredCompaction(
-      const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
-      VersionStorageInfo* vstorage, double score,
-      const std::vector<SortedRun>& sorted_runs, LogBuffer* log_buffer);
-
-  // Used in universal compaction when the enabled_trivial_move
-  // option is set. Checks whether there are any overlapping files
-  // in the input. Returns true if the input files are non
-  // overlapping.
-  bool IsInputFilesNonOverlapping(Compaction* c);
-
-  static std::vector<SortedRun> CalculateSortedRuns(
-      const VersionStorageInfo& vstorage, const ImmutableCFOptions& ioptions,
-      const MutableCFOptions& mutable_cf_options);
-
-  // Pick a path ID to place a newly generated file, with its estimated file
-  // size.
-  static uint32_t GetPathId(const ImmutableCFOptions& ioptions,
-                            const MutableCFOptions& mutable_cf_options,
-                            uint64_t file_size);
 };
 }  // namespace rocksdb
 #endif  // !ROCKSDB_LITE
@@ -35,14 +35,22 @@ Status DeleteFilesInRanges(DB* db, ColumnFamilyHandle* column_family,
 Status VerifySstFileChecksum(const Options& options,
                             const EnvOptions& env_options,
                             const std::string& file_path) {
-  std::unique_ptr<RandomAccessFile> file;
+  return VerifySstFileChecksum(options, env_options, ReadOptions(), file_path);
+}
+Status VerifySstFileChecksum(const Options& options,
+                             const EnvOptions& env_options,
+                             const ReadOptions& read_options,
+                             const std::string& file_path) {
+  std::unique_ptr<FSRandomAccessFile> file;
  uint64_t file_size;
  InternalKeyComparator internal_comparator(options.comparator);
  ImmutableCFOptions ioptions(options);

-  Status s = ioptions.env->NewRandomAccessFile(file_path, &file, env_options);
+  Status s = ioptions.fs->NewRandomAccessFile(file_path,
+                                              FileOptions(env_options),
+                                              &file, nullptr);
  if (s.ok()) {
-    s = ioptions.env->GetFileSize(file_path, &file_size);
+    s = ioptions.fs->GetFileSize(file_path, IOOptions(), &file_size, nullptr);
  } else {
    return s;
  }
@@ -59,7 +67,8 @@ Status VerifySstFileChecksum(const Options& options,
  if (!s.ok()) {
    return s;
  }
-  s = table_reader->VerifyChecksum(TableReaderCaller::kUserVerifyChecksum);
+  s = table_reader->VerifyChecksum(read_options,
+                                   TableReaderCaller::kUserVerifyChecksum);
  return s;
 }

@@ -13,12 +13,14 @@

 #include <errno.h>
 #include <fcntl.h>
-#include <cinttypes>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <cinttypes>
 #include "db/db_impl/db_impl.h"
+#include "db/db_test_util.h"
 #include "db/log_format.h"
 #include "db/version_set.h"
+#include "env/composite_env_wrapper.h"
 #include "file/filename.h"
 #include "rocksdb/cache.h"
 #include "rocksdb/convenience.h"
@@ -76,7 +78,11 @@ class CorruptionTest : public testing::Test {
    delete db_;
    db_ = nullptr;
    Options opt = (options ? *options : options_);
-    opt.env = &env_;
+    if (opt.env == Options().env) {
+      // If env is not overridden, replace it with ErrorEnv.
+      // Otherwise, the test already uses a non-default Env.
+      opt.env = &env_;
+    }
    opt.arena_block_size = 4096;
    BlockBasedTableOptions table_options;
    table_options.block_cache = tiny_cache_;
@@ -184,6 +190,7 @@ class CorruptionTest : public testing::Test {
    ASSERT_TRUE(s.ok()) << s.ToString();
    Options options;
    EnvOptions env_options;
+    options.file_system.reset(new LegacyFileSystemWrapper(options.env));
    ASSERT_NOK(VerifySstFileChecksum(options, env_options, fname));
  }

@@ -321,6 +328,59 @@ TEST_F(CorruptionTest, TableFile) {
  ASSERT_NOK(dbi->VerifyChecksum());
 }

+TEST_F(CorruptionTest, VerifyChecksumReadahead) {
+  Options options;
+  SpecialEnv senv(Env::Default());
+  options.env = &senv;
+  // Disable block cache as we are going to check checksum for
+  // the same file twice and measure number of reads.
+  BlockBasedTableOptions table_options_no_bc;
+  table_options_no_bc.no_block_cache = true;
+  options.table_factory.reset(NewBlockBasedTableFactory(table_options_no_bc));
+
+  Reopen(&options);
+
+  Build(10000);
+  DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
+  dbi->TEST_FlushMemTable();
+  dbi->TEST_CompactRange(0, nullptr, nullptr);
+  dbi->TEST_CompactRange(1, nullptr, nullptr);
+
+  senv.count_random_reads_ = true;
+  senv.random_read_counter_.Reset();
+  ASSERT_OK(dbi->VerifyChecksum());
+
+  // Make sure the counter is enabled.
+  ASSERT_GT(senv.random_read_counter_.Read(), 0);
+
+  // The SST file is about 10MB. Default readahead size is 256KB.
+  // Give a conservative 20 reads for metadata blocks, The number
+  // of random reads should be within 10 MB / 256KB + 20 = 60.
+  ASSERT_LT(senv.random_read_counter_.Read(), 60);
+
+  senv.random_read_bytes_counter_ = 0;
+  ReadOptions ro;
+  ro.readahead_size = size_t{32 * 1024};
+  ASSERT_OK(dbi->VerifyChecksum(ro));
+  // The SST file is about 10MB. We set readahead size to 32KB.
+  // Give 0 to 20 reads for metadata blocks, and allow real read
+  // to range from 24KB to 48KB. The lower bound would be:
+  //   10MB / 48KB + 0 = 213
+  // The higher bound is
+  //   10MB / 24KB + 20 = 447.
+  ASSERT_GE(senv.random_read_counter_.Read(), 213);
+  ASSERT_LE(senv.random_read_counter_.Read(), 447);
+
+  // Test readahead shouldn't break mmap mode (where it should be
+  // disabled).
+  options.allow_mmap_reads = true;
+  Reopen(&options);
+  dbi = static_cast<DBImpl*>(db_);
+  ASSERT_OK(dbi->VerifyChecksum(ro));
+
+  CloseDb();
+}
+
 TEST_F(CorruptionTest, TableFileIndexData) {
  Options options;
  // very big, we'll trigger flushes manually
@@ -481,7 +541,8 @@ TEST_F(CorruptionTest, RangeDeletionCorrupted) {
  std::unique_ptr<RandomAccessFile> file;
  ASSERT_OK(options_.env->NewRandomAccessFile(filename, &file, EnvOptions()));
  std::unique_ptr<RandomAccessFileReader> file_reader(
-      new RandomAccessFileReader(std::move(file), filename));
+      new RandomAccessFileReader(NewLegacyRandomAccessFileWrapper(file),
+                                 filename));

  uint64_t file_size;
  ASSERT_OK(options_.env->GetFileSize(filename, &file_size));
@@ -285,6 +285,9 @@ TEST_F(CuckooTableDBTest, SameKeyInsertedInTwoDifferentFilesAndCompacted) {
 TEST_F(CuckooTableDBTest, AdaptiveTable) {
  Options options = CurrentOptions();

+  // Ensure options compatible with PlainTable
+  options.prefix_extractor.reset(NewCappedPrefixTransform(8));
+
  // Write some keys using cuckoo table.
  options.table_factory.reset(NewCuckooTableFactory());
  Reopen(&options);
@@ -12,6 +12,7 @@
 #include <utility>
 #include <vector>

+#include "db/arena_wrapped_db_iter.h"
 #include "db/column_family.h"
 #include "db/db_iter.h"
 #include "db/db_test_util.h"
@@ -63,9 +64,11 @@ class DBBlobIndexTest : public DBTestBase {
    ReadOptions read_options;
    read_options.snapshot = snapshot;
    PinnableSlice value;
-    auto s = dbfull()->GetImpl(read_options, cfh(), key, &value,
-                               nullptr /*value_found*/, nullptr /*callback*/,
-                               is_blob_index);
+    DBImpl::GetImplOptions get_impl_options;
+    get_impl_options.column_family = cfh();
+    get_impl_options.value = &value;
+    get_impl_options.is_blob_index = is_blob_index;
+    auto s = dbfull()->GetImpl(read_options, key, get_impl_options);
    if (s.IsNotFound()) {
      return "NOT_FOUND";
    }
@@ -395,6 +398,29 @@ TEST_F(DBBlobIndexTest, Iterate) {
    verify(15, Status::kOk, get_value(16, 0), get_value(14, 0),
           create_blob_iterator, check_is_blob(false));

+#ifndef ROCKSDB_LITE
+    // Iterator with blob support and using seek.
+    ASSERT_OK(dbfull()->SetOptions(
+        cfh(), {{"max_sequential_skip_in_iterations", "0"}}));
+    verify(1, Status::kOk, get_value(1, 0), get_value(1, 0),
+           create_blob_iterator, check_is_blob(true));
+    verify(3, Status::kOk, get_value(3, 0), get_value(3, 0),
+           create_blob_iterator, check_is_blob(true));
+    verify(5, Status::kOk, get_value(5, 0), get_value(5, 0),
+           create_blob_iterator, check_is_blob(false));
+    verify(7, Status::kOk, get_value(8, 0), get_value(6, 0),
+           create_blob_iterator, check_is_blob(false));
+    verify(9, Status::kOk, get_value(10, 0), get_value(8, 0),
+           create_blob_iterator, check_is_blob(false));
+    verify(11, Status::kNotSupported, "", "", create_blob_iterator);
+    verify(13, Status::kOk,
+           get_value(13, 2) + "," + get_value(13, 1) + "," + get_value(13, 0),
+           get_value(13, 2) + "," + get_value(13, 1) + "," + get_value(13, 0),
+           create_blob_iterator, check_is_blob(false));
+    verify(15, Status::kOk, get_value(16, 0), get_value(14, 0),
+           create_blob_iterator, check_is_blob(false));
+#endif  // !ROCKSDB_LITE
+
    for (auto* snapshot : snapshots) {
      dbfull()->ReleaseSnapshot(snapshot);
    }
@@ -10,6 +10,7 @@
 #include "cache/lru_cache.h"
 #include "db/db_test_util.h"
 #include "port/stack_trace.h"
+#include "util/compression.h"

 namespace rocksdb {

@@ -380,8 +381,13 @@ TEST_F(DBBlockCacheTest, IndexAndFilterBlocksStats) {
  options.statistics = rocksdb::CreateDBStatistics();
  BlockBasedTableOptions table_options;
  table_options.cache_index_and_filter_blocks = true;
+  LRUCacheOptions co;
  // 500 bytes are enough to hold the first two blocks
-  std::shared_ptr<Cache> cache = NewLRUCache(500, 0, false);
+  co.capacity = 500;
+  co.num_shard_bits = 0;
+  co.strict_capacity_limit = false;
+  co.metadata_charge_policy = kDontChargeCacheMetadata;
+  std::shared_ptr<Cache> cache = NewLRUCache(co);
  table_options.block_cache = cache;
  table_options.filter_policy.reset(NewBloomFilterPolicy(20, true));
  options.table_factory.reset(new BlockBasedTableFactory(table_options));
@@ -484,11 +490,11 @@ TEST_F(DBBlockCacheTest, IndexAndFilterBlocksCachePriority) {
              TestGetTickerCount(options, BLOCK_CACHE_ADD));
    ASSERT_EQ(0, TestGetTickerCount(options, BLOCK_CACHE_DATA_MISS));
    if (priority == Cache::Priority::LOW) {
-      ASSERT_EQ(0, MockCache::high_pri_insert_count);
-      ASSERT_EQ(2, MockCache::low_pri_insert_count);
+      ASSERT_EQ(0u, MockCache::high_pri_insert_count);
+      ASSERT_EQ(2u, MockCache::low_pri_insert_count);
    } else {
-      ASSERT_EQ(2, MockCache::high_pri_insert_count);
-      ASSERT_EQ(0, MockCache::low_pri_insert_count);
+      ASSERT_EQ(2u, MockCache::high_pri_insert_count);
+      ASSERT_EQ(0u, MockCache::low_pri_insert_count);
    }

    // Access data block.
@@ -502,11 +508,11 @@ TEST_F(DBBlockCacheTest, IndexAndFilterBlocksCachePriority) {

    // Data block should be inserted with low priority.
    if (priority == Cache::Priority::LOW) {
-      ASSERT_EQ(0, MockCache::high_pri_insert_count);
-      ASSERT_EQ(3, MockCache::low_pri_insert_count);
+      ASSERT_EQ(0u, MockCache::high_pri_insert_count);
+      ASSERT_EQ(3u, MockCache::low_pri_insert_count);
    } else {
-      ASSERT_EQ(2, MockCache::high_pri_insert_count);
-      ASSERT_EQ(1, MockCache::low_pri_insert_count);
+      ASSERT_EQ(2u, MockCache::high_pri_insert_count);
+      ASSERT_EQ(1u, MockCache::low_pri_insert_count);
    }
  }
 }
@@ -680,16 +686,18 @@ TEST_F(DBBlockCacheTest, CacheCompressionDict) {

  // Try all the available libraries that support dictionary compression
  std::vector<CompressionType> compression_types;
-#ifdef ZLIB
-  compression_types.push_back(kZlibCompression);
-#endif  // ZLIB
-#if LZ4_VERSION_NUMBER >= 10400
-  compression_types.push_back(kLZ4Compression);
-  compression_types.push_back(kLZ4HCCompression);
-#endif  // LZ4_VERSION_NUMBER >= 10400
-#if ZSTD_VERSION_NUMBER >= 500
-  compression_types.push_back(kZSTD);
-#endif  // ZSTD_VERSION_NUMBER >= 500
+  if (Zlib_Supported()) {
+    compression_types.push_back(kZlibCompression);
+  }
+  if (LZ4_Supported()) {
+    compression_types.push_back(kLZ4Compression);
+    compression_types.push_back(kLZ4HCCompression);
+  }
+  if (ZSTD_Supported()) {
+    compression_types.push_back(kZSTD);
+  } else if (ZSTDNotFinal_Supported()) {
+    compression_types.push_back(kZSTDNotFinalCompression);
+  }
  Random rnd(301);
  for (auto compression_type : compression_types) {
    Options options = CurrentOptions();
@@ -10,9 +10,20 @@
 #include "db/db_test_util.h"
 #include "port/stack_trace.h"
 #include "rocksdb/perf_context.h"
+#include "table/block_based/filter_policy_internal.h"

 namespace rocksdb {

+namespace {
+using BFP = BloomFilterPolicy;
+
+namespace BFP2 {
+// Extends BFP::Mode with option to use Plain table
+using PseudoMode = int;
+static constexpr PseudoMode kPlainTable = -1;
+}  // namespace BFP2
+}  // namespace
+
 // DB tests related to bloom filter.

 class DBBloomFilterTest : public DBTestBase {
@@ -20,12 +31,12 @@ class DBBloomFilterTest : public DBTestBase {
  DBBloomFilterTest() : DBTestBase("/db_bloom_filter_test") {}
 };

-class DBBloomFilterTestWithParam
-    : public DBTestBase,
-      public testing::WithParamInterface<std::tuple<bool, bool, uint32_t>> {
+class DBBloomFilterTestWithParam : public DBTestBase,
+                                   public testing::WithParamInterface<
+                                       std::tuple<BFP::Mode, bool, uint32_t>> {
  //                             public testing::WithParamInterface<bool> {
 protected:
-  bool use_block_based_filter_;
+  BFP::Mode bfp_impl_;
  bool partition_filters_;
  uint32_t format_version_;

@@ -35,7 +46,7 @@ class DBBloomFilterTestWithParam
  ~DBBloomFilterTestWithParam() override {}

  void SetUp() override {
-    use_block_based_filter_ = std::get<0>(GetParam());
+    bfp_impl_ = std::get<0>(GetParam());
    partition_filters_ = std::get<1>(GetParam());
    format_version_ = std::get<2>(GetParam());
  }
@@ -71,8 +82,7 @@ TEST_P(DBBloomFilterTestDefFormatVersion, KeyMayExist) {
    ReadOptions ropts;
    std::string value;
    anon::OptionsOverride options_override;
-    options_override.filter_policy.reset(
-        NewBloomFilterPolicy(20, use_block_based_filter_));
+    options_override.filter_policy.reset(new BFP(20, bfp_impl_));
    options_override.partition_filters = partition_filters_;
    options_override.metadata_block_size = 32;
    Options options = CurrentOptions(options_override);
@@ -432,8 +442,7 @@ TEST_P(DBBloomFilterTestWithParam, BloomFilter) {
    // trigger reset of table_factory
    BlockBasedTableOptions table_options;
    table_options.no_block_cache = true;
-    table_options.filter_policy.reset(
-        NewBloomFilterPolicy(10, use_block_based_filter_));
+    table_options.filter_policy.reset(new BFP(10, bfp_impl_));
    table_options.partition_filters = partition_filters_;
    if (partition_filters_) {
      table_options.index_type =
@@ -502,24 +511,27 @@ TEST_P(DBBloomFilterTestWithParam, BloomFilter) {
 #ifndef ROCKSDB_VALGRIND_RUN
 INSTANTIATE_TEST_CASE_P(
    FormatDef, DBBloomFilterTestDefFormatVersion,
-    ::testing::Values(std::make_tuple(true, false, test::kDefaultFormatVersion),
-                      std::make_tuple(false, true, test::kDefaultFormatVersion),
-                      std::make_tuple(false, false,
-                                      test::kDefaultFormatVersion)));
+    ::testing::Values(
+        std::make_tuple(BFP::kDeprecatedBlock, false,
+                        test::kDefaultFormatVersion),
+        std::make_tuple(BFP::kAuto, true, test::kDefaultFormatVersion),
+        std::make_tuple(BFP::kAuto, false, test::kDefaultFormatVersion)));

 INSTANTIATE_TEST_CASE_P(
    FormatDef, DBBloomFilterTestWithParam,
-    ::testing::Values(std::make_tuple(true, false, test::kDefaultFormatVersion),
-                      std::make_tuple(false, true, test::kDefaultFormatVersion),
-                      std::make_tuple(false, false,
-                                      test::kDefaultFormatVersion)));
+    ::testing::Values(
+        std::make_tuple(BFP::kDeprecatedBlock, false,
+                        test::kDefaultFormatVersion),
+        std::make_tuple(BFP::kAuto, true, test::kDefaultFormatVersion),
+        std::make_tuple(BFP::kAuto, false, test::kDefaultFormatVersion)));

 INSTANTIATE_TEST_CASE_P(
    FormatLatest, DBBloomFilterTestWithParam,
-    ::testing::Values(std::make_tuple(true, false, test::kLatestFormatVersion),
-                      std::make_tuple(false, true, test::kLatestFormatVersion),
-                      std::make_tuple(false, false,
-                                      test::kLatestFormatVersion)));
+    ::testing::Values(
+        std::make_tuple(BFP::kDeprecatedBlock, false,
+                        test::kLatestFormatVersion),
+        std::make_tuple(BFP::kAuto, true, test::kLatestFormatVersion),
+        std::make_tuple(BFP::kAuto, false, test::kLatestFormatVersion)));
 #endif  // ROCKSDB_VALGRIND_RUN

 TEST_F(DBBloomFilterTest, BloomFilterRate) {
@@ -636,15 +648,17 @@ TEST_F(DBBloomFilterTest, BloomFilterReverseCompatibility) {
 }

 namespace {
-// A wrapped bloom over default FilterPolicy
-class WrappedBloom : public FilterPolicy {
+// A wrapped bloom over block-based FilterPolicy
+class TestingWrappedBlockBasedFilterPolicy : public FilterPolicy {
 public:
-  explicit WrappedBloom(int bits_per_key)
-      : filter_(NewBloomFilterPolicy(bits_per_key)), counter_(0) {}
+  explicit TestingWrappedBlockBasedFilterPolicy(int bits_per_key)
+      : filter_(NewBloomFilterPolicy(bits_per_key, true)), counter_(0) {}

-  ~WrappedBloom() override { delete filter_; }
+  ~TestingWrappedBlockBasedFilterPolicy() override { delete filter_; }

-  const char* Name() const override { return "WrappedRocksDbFilterPolicy"; }
+  const char* Name() const override {
+    return "TestingWrappedBlockBasedFilterPolicy";
+  }

  void CreateFilter(const rocksdb::Slice* keys, int n,
                    std::string* dst) const override {
@@ -671,12 +685,13 @@ class WrappedBloom : public FilterPolicy {
 };
 }  // namespace

-TEST_F(DBBloomFilterTest, BloomFilterWrapper) {
+TEST_F(DBBloomFilterTest, WrappedBlockBasedFilterPolicy) {
  Options options = CurrentOptions();
  options.statistics = rocksdb::CreateDBStatistics();

  BlockBasedTableOptions table_options;
-  WrappedBloom* policy = new WrappedBloom(10);
+  TestingWrappedBlockBasedFilterPolicy* policy =
+      new TestingWrappedBlockBasedFilterPolicy(10);
  table_options.filter_policy.reset(policy);
  options.table_factory.reset(NewBlockBasedTableFactory(table_options));

@@ -706,6 +721,166 @@ TEST_F(DBBloomFilterTest, BloomFilterWrapper) {
  ASSERT_EQ(2U * maxKey, policy->GetCounter());
 }

+namespace {
+// NOTE: This class is referenced by HISTORY.md as a model for a wrapper
+// FilterPolicy selecting among configurations based on context.
+class LevelAndStyleCustomFilterPolicy : public FilterPolicy {
+ public:
+  explicit LevelAndStyleCustomFilterPolicy(int bpk_fifo, int bpk_l0_other,
+                                           int bpk_otherwise)
+      : policy_fifo_(NewBloomFilterPolicy(bpk_fifo)),
+        policy_l0_other_(NewBloomFilterPolicy(bpk_l0_other)),
+        policy_otherwise_(NewBloomFilterPolicy(bpk_otherwise)) {}
+
+  // OK to use built-in policy name because we are deferring to a
+  // built-in builder. We aren't changing the serialized format.
+  const char* Name() const override { return policy_fifo_->Name(); }
+
+  FilterBitsBuilder* GetBuilderWithContext(
+      const FilterBuildingContext& context) const override {
+    if (context.compaction_style == kCompactionStyleFIFO) {
+      return policy_fifo_->GetBuilderWithContext(context);
+    } else if (context.level_at_creation == 0) {
+      return policy_l0_other_->GetBuilderWithContext(context);
+    } else {
+      return policy_otherwise_->GetBuilderWithContext(context);
+    }
+  }
+
+  FilterBitsReader* GetFilterBitsReader(const Slice& contents) const override {
+    // OK to defer to any of them; they all can parse built-in filters
+    // from any settings.
+    return policy_fifo_->GetFilterBitsReader(contents);
+  }
+
+  // Defer just in case configuration uses block-based filter
+  void CreateFilter(const Slice* keys, int n, std::string* dst) const override {
+    policy_otherwise_->CreateFilter(keys, n, dst);
+  }
+  bool KeyMayMatch(const Slice& key, const Slice& filter) const override {
+    return policy_otherwise_->KeyMayMatch(key, filter);
+  }
+
+ private:
+  const std::unique_ptr<const FilterPolicy> policy_fifo_;
+  const std::unique_ptr<const FilterPolicy> policy_l0_other_;
+  const std::unique_ptr<const FilterPolicy> policy_otherwise_;
+};
+
+class TestingContextCustomFilterPolicy
+    : public LevelAndStyleCustomFilterPolicy {
+ public:
+  explicit TestingContextCustomFilterPolicy(int bpk_fifo, int bpk_l0_other,
+                                            int bpk_otherwise)
+      : LevelAndStyleCustomFilterPolicy(bpk_fifo, bpk_l0_other, bpk_otherwise) {
+  }
+
+  FilterBitsBuilder* GetBuilderWithContext(
+      const FilterBuildingContext& context) const override {
+    test_report_ += "cf=";
+    test_report_ += context.column_family_name;
+    test_report_ += ",cs=";
+    test_report_ +=
+        OptionsHelper::compaction_style_to_string[context.compaction_style];
+    test_report_ += ",lv=";
+    test_report_ += std::to_string(context.level_at_creation);
+    test_report_ += "\n";
+
+    return LevelAndStyleCustomFilterPolicy::GetBuilderWithContext(context);
+  }
+
+  std::string DumpTestReport() {
+    std::string rv;
+    std::swap(rv, test_report_);
+    return rv;
+  }
+
+ private:
+  mutable std::string test_report_;
+};
+}  // namespace
+
+TEST_F(DBBloomFilterTest, ContextCustomFilterPolicy) {
+  for (bool fifo : {true, false}) {
+    Options options = CurrentOptions();
+    options.statistics = rocksdb::CreateDBStatistics();
+    options.compaction_style =
+        fifo ? kCompactionStyleFIFO : kCompactionStyleLevel;
+
+    BlockBasedTableOptions table_options;
+    auto policy = std::make_shared<TestingContextCustomFilterPolicy>(15, 8, 5);
+    table_options.filter_policy = policy;
+    table_options.format_version = 5;
+    options.table_factory.reset(NewBlockBasedTableFactory(table_options));
+
+    CreateAndReopenWithCF({fifo ? "abe" : "bob"}, options);
+
+    const int maxKey = 10000;
+    for (int i = 0; i < maxKey / 2; i++) {
+      ASSERT_OK(Put(1, Key(i), Key(i)));
+    }
+    // Add a large key to make the file contain wide range
+    ASSERT_OK(Put(1, Key(maxKey + 55555), Key(maxKey + 55555)));
+    Flush(1);
+    EXPECT_EQ(policy->DumpTestReport(),
+              fifo ? "cf=abe,cs=kCompactionStyleFIFO,lv=0\n"
+                   : "cf=bob,cs=kCompactionStyleLevel,lv=0\n");
+
+    for (int i = maxKey / 2; i < maxKey; i++) {
+      ASSERT_OK(Put(1, Key(i), Key(i)));
+    }
+    Flush(1);
+    EXPECT_EQ(policy->DumpTestReport(),
+              fifo ? "cf=abe,cs=kCompactionStyleFIFO,lv=0\n"
+                   : "cf=bob,cs=kCompactionStyleLevel,lv=0\n");
+
+    // Check that they can be found
+    for (int i = 0; i < maxKey; i++) {
+      ASSERT_EQ(Key(i), Get(1, Key(i)));
+    }
+    // Since we have two tables / two filters, we might have Bloom checks on
+    // our queries, but no more than one "useful" per query on a found key.
+    EXPECT_LE(TestGetAndResetTickerCount(options, BLOOM_FILTER_USEFUL), maxKey);
+
+    // Check that we have two filters, each about
+    // fifo: 0.12% FP rate (15 bits per key)
+    // level: 2.3% FP rate (8 bits per key)
+    for (int i = 0; i < maxKey; i++) {
+      ASSERT_EQ("NOT_FOUND", Get(1, Key(i + 33333)));
+    }
+    {
+      auto useful_count =
+          TestGetAndResetTickerCount(options, BLOOM_FILTER_USEFUL);
+      EXPECT_GE(useful_count, maxKey * 2 * (fifo ? 0.9980 : 0.975));
+      EXPECT_LE(useful_count, maxKey * 2 * (fifo ? 0.9995 : 0.98));
+    }
+
+    if (!fifo) {  // FIFO only has L0
+      // Full compaction
+      ASSERT_OK(db_->CompactRange(CompactRangeOptions(), handles_[1], nullptr,
+                                  nullptr));
+      EXPECT_EQ(policy->DumpTestReport(),
+                "cf=bob,cs=kCompactionStyleLevel,lv=1\n");
+
+      // Check that we now have one filter, about 9.2% FP rate (5 bits per key)
+      for (int i = 0; i < maxKey; i++) {
+        ASSERT_EQ("NOT_FOUND", Get(1, Key(i + 33333)));
+      }
+      {
+        auto useful_count =
+            TestGetAndResetTickerCount(options, BLOOM_FILTER_USEFUL);
+        EXPECT_GE(useful_count, maxKey * 0.90);
+        EXPECT_LE(useful_count, maxKey * 0.91);
+      }
+    }
+
+    // Destroy
+    ASSERT_OK(dbfull()->DropColumnFamily(handles_[1]));
+    dbfull()->DestroyColumnFamilyHandle(handles_[1]);
+    handles_[1] = nullptr;
+  }
+}
+
 class SliceTransformLimitedDomain : public SliceTransform {
  const char* Name() const override { return "SliceTransformLimitedDomain"; }

@@ -858,33 +1033,32 @@ TEST_F(DBBloomFilterTest, MemtablePrefixBloomOutOfDomain) {
 #ifndef ROCKSDB_LITE
 class BloomStatsTestWithParam
    : public DBBloomFilterTest,
-      public testing::WithParamInterface<std::tuple<bool, bool, bool>> {
+      public testing::WithParamInterface<std::tuple<BFP2::PseudoMode, bool>> {
 public:
  BloomStatsTestWithParam() {
-    use_block_table_ = std::get<0>(GetParam());
-    use_block_based_builder_ = std::get<1>(GetParam());
-    partition_filters_ = std::get<2>(GetParam());
+    bfp_impl_ = std::get<0>(GetParam());
+    partition_filters_ = std::get<1>(GetParam());

    options_.create_if_missing = true;
    options_.prefix_extractor.reset(rocksdb::NewFixedPrefixTransform(4));
    options_.memtable_prefix_bloom_size_ratio =
        8.0 * 1024.0 / static_cast<double>(options_.write_buffer_size);
-    if (use_block_table_) {
+    if (bfp_impl_ == BFP2::kPlainTable) {
+      assert(!partition_filters_);  // not supported in plain table
+      PlainTableOptions table_options;
+      options_.table_factory.reset(NewPlainTableFactory(table_options));
+    } else {
      BlockBasedTableOptions table_options;
      table_options.hash_index_allow_collision = false;
      if (partition_filters_) {
-        assert(!use_block_based_builder_);
+        assert(bfp_impl_ != BFP::kDeprecatedBlock);
        table_options.partition_filters = partition_filters_;
        table_options.index_type =
            BlockBasedTableOptions::IndexType::kTwoLevelIndexSearch;
      }
      table_options.filter_policy.reset(
-          NewBloomFilterPolicy(10, use_block_based_builder_));
+          new BFP(10, static_cast<BFP::Mode>(bfp_impl_)));
      options_.table_factory.reset(NewBlockBasedTableFactory(table_options));
-    } else {
-      assert(!partition_filters_);  // not supported in plain table
-      PlainTableOptions table_options;
-      options_.table_factory.reset(NewPlainTableFactory(table_options));
    }
    options_.env = env_;

@@ -901,8 +1075,7 @@ class BloomStatsTestWithParam
  static void SetUpTestCase() {}
  static void TearDownTestCase() {}

-  bool use_block_table_;
-  bool use_block_based_builder_;
+  BFP2::PseudoMode bfp_impl_;
  bool partition_filters_;
  Options options_;
 };
@@ -1006,7 +1179,7 @@ TEST_P(BloomStatsTestWithParam, BloomStatsTestWithIter) {
  ASSERT_EQ(value3, iter->value().ToString());
  // The seek doesn't check block-based bloom filter because last index key
  // starts with the same prefix we're seeking to.
-  uint64_t expected_hits = use_block_based_builder_ ? 1 : 2;
+  uint64_t expected_hits = bfp_impl_ == BFP::kDeprecatedBlock ? 1 : 2;
  ASSERT_EQ(expected_hits, get_perf_context()->bloom_sst_hit_count);

  iter->Seek(key2);
@@ -1016,12 +1189,14 @@ TEST_P(BloomStatsTestWithParam, BloomStatsTestWithIter) {
  ASSERT_EQ(expected_hits, get_perf_context()->bloom_sst_hit_count);
 }

-INSTANTIATE_TEST_CASE_P(BloomStatsTestWithParam, BloomStatsTestWithParam,
-                        ::testing::Values(std::make_tuple(true, true, false),
-                                          std::make_tuple(true, false, false),
-                                          std::make_tuple(true, false, true),
-                                          std::make_tuple(false, false,
-                                                          false)));
+INSTANTIATE_TEST_CASE_P(
+    BloomStatsTestWithParam, BloomStatsTestWithParam,
+    ::testing::Values(std::make_tuple(BFP::kDeprecatedBlock, false),
+                      std::make_tuple(BFP::kLegacyBloom, false),
+                      std::make_tuple(BFP::kLegacyBloom, true),
+                      std::make_tuple(BFP::kFastLocalBloom, false),
+                      std::make_tuple(BFP::kFastLocalBloom, true),
+                      std::make_tuple(BFP2::kPlainTable, false)));

 namespace {
 void PrefixScanInit(DBBloomFilterTest* dbtest) {
@@ -1147,6 +1322,7 @@ TEST_F(DBBloomFilterTest, OptimizeFiltersForHits) {
  options.table_factory.reset(NewBlockBasedTableFactory(bbto));
  options.optimize_filters_for_hits = true;
  options.statistics = rocksdb::CreateDBStatistics();
+  get_perf_context()->Reset();
  get_perf_context()->EnablePerLevelPerfContext();
  CreateAndReopenWithCF({"mypikachu"}, options);

@@ -1328,8 +1504,8 @@ int CountIter(std::unique_ptr<Iterator>& iter, const Slice& key) {
 // into the same string, or 2) the transformed seek key is of the same length
 // as the upper bound and two keys are adjacent according to the comparator.
 TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
-  int iteration = 0;
-  for (bool use_block_based_builder : {true, false}) {
+  for (auto bfp_impl : BFP::kAllFixedImpls) {
+    int using_full_builder = bfp_impl != BFP::kDeprecatedBlock;
    Options options;
    options.create_if_missing = true;
    options.prefix_extractor.reset(NewCappedPrefixTransform(4));
@@ -1338,8 +1514,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
    // Enable prefix bloom for SST files
    BlockBasedTableOptions table_options;
    table_options.cache_index_and_filter_blocks = true;
-    table_options.filter_policy.reset(
-        NewBloomFilterPolicy(10, use_block_based_builder));
+    table_options.filter_policy.reset(new BFP(10, bfp_impl));
    table_options.index_shortening = BlockBasedTableOptions::
        IndexShorteningMode::kShortenSeparatorsAndSuccessor;
    options.table_factory.reset(NewBlockBasedTableFactory(table_options));
@@ -1382,7 +1557,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
      ASSERT_EQ(CountIter(iter, "abcdxx00"), 4);
      // should check bloom filter since upper bound meets requirement
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                2 + iteration);
+                2 + using_full_builder);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);
    }
    {
@@ -1396,7 +1571,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
      ASSERT_EQ(CountIter(iter, "abcdxx01"), 4);
      // should skip bloom filter since upper bound is too long
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                2 + iteration);
+                2 + using_full_builder);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);
    }
    {
@@ -1410,7 +1585,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
      // should check bloom filter since upper bound matches transformed seek
      // key
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                2 + iteration * 2);
+                2 + using_full_builder * 2);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);
    }
    {
@@ -1424,7 +1599,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
      ASSERT_EQ(CountIter(iter, "aaaaaaaa"), 0);
      // should skip bloom filter since mismatch is found
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                2 + iteration * 2);
+                2 + using_full_builder * 2);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);
    }
    ASSERT_OK(dbfull()->SetOptions({{"prefix_extractor", "fixed:3"}}));
@@ -1438,7 +1613,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
      std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
      ASSERT_EQ(CountIter(iter, "abc"), 4);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                2 + iteration * 2);
+                2 + using_full_builder * 2);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);
    }
    ASSERT_OK(dbfull()->SetOptions({{"prefix_extractor", "capped:4"}}));
@@ -1451,18 +1626,17 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterUpperBound) {
      std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
      ASSERT_EQ(CountIter(iter, "abc"), 0);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                3 + iteration * 2);
+                3 + using_full_builder * 2);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 1);
    }
-    iteration++;
  }
 }

 // Create multiple SST files each with a different prefix_extractor config,
 // verify iterators can read all SST files using the latest config.
 TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
-  int iteration = 0;
-  for (bool use_block_based_builder : {true, false}) {
+  for (auto bfp_impl : BFP::kAllFixedImpls) {
+    int using_full_builder = bfp_impl != BFP::kDeprecatedBlock;
    Options options;
    options.create_if_missing = true;
    options.prefix_extractor.reset(NewFixedPrefixTransform(1));
@@ -1470,8 +1644,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
    options.statistics = CreateDBStatistics();
    // Enable prefix bloom for SST files
    BlockBasedTableOptions table_options;
-    table_options.filter_policy.reset(
-        NewBloomFilterPolicy(10, use_block_based_builder));
+    table_options.filter_policy.reset(new BFP(10, bfp_impl));
    table_options.cache_index_and_filter_blocks = true;
    options.table_factory.reset(NewBlockBasedTableFactory(table_options));
    DestroyAndReopen(options);
@@ -1497,10 +1670,10 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_EQ(CountIter(iter, "foo"), 2);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-              1 + iteration);
+              1 + using_full_builder);
    ASSERT_EQ(CountIter(iter, "gpk"), 0);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-              1 + iteration);
+              1 + using_full_builder);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);

    // second SST with capped:3 BF
@@ -1514,13 +1687,13 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
      std::unique_ptr<Iterator> iter_tmp(db_->NewIterator(read_options));
      ASSERT_EQ(CountIter(iter_tmp, "foo"), 4);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                2 + iteration * 2);
+                2 + using_full_builder * 2);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 0);
      ASSERT_EQ(CountIter(iter_tmp, "gpk"), 0);
      // both counters are incremented because BF is "not changed" for 1 of the
      // 2 SST files, so filter is checked once and found no match.
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                3 + iteration * 2);
+                3 + using_full_builder * 2);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 1);
    }

@@ -1539,24 +1712,24 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
      ASSERT_EQ(CountIter(iter_tmp, "foo"), 9);
      // the first and last BF are checked
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                4 + iteration * 3);
+                4 + using_full_builder * 3);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 1);
      ASSERT_EQ(CountIter(iter_tmp, "gpk"), 0);
      // only last BF is checked and not found
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                5 + iteration * 3);
+                5 + using_full_builder * 3);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 2);
    }

    // iter_old can only see the first SST, so checked plus 1
    ASSERT_EQ(CountIter(iter_old, "foo"), 4);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-              6 + iteration * 3);
+              6 + using_full_builder * 3);
    // iter was created after the first setoptions call so only full filter
    // will check the filter
    ASSERT_EQ(CountIter(iter, "foo"), 2);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-              6 + iteration * 4);
+              6 + using_full_builder * 4);

    {
      // keys in all three SSTs are visible to iterator
@@ -1565,11 +1738,11 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
      std::unique_ptr<Iterator> iter_all(db_->NewIterator(read_options));
      ASSERT_EQ(CountIter(iter_all, "foo"), 9);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                7 + iteration * 5);
+                7 + using_full_builder * 5);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 2);
      ASSERT_EQ(CountIter(iter_all, "gpk"), 0);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                8 + iteration * 5);
+                8 + using_full_builder * 5);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 3);
    }
    ASSERT_OK(dbfull()->SetOptions({{"prefix_extractor", "capped:3"}}));
@@ -1581,15 +1754,14 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
      // all three SST are checked because the current options has the same as
      // the remaining SST (capped:3)
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                9 + iteration * 7);
+                9 + using_full_builder * 7);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 3);
      ASSERT_EQ(CountIter(iter_all, "gpk"), 0);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED),
-                10 + iteration * 7);
+                10 + using_full_builder * 7);
      ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 4);
    }
    // TODO(Zhongyi): Maybe also need to add Get calls to test point look up?
-    iteration++;
  }
 }

@@ -1598,7 +1770,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterMultipleSST) {
 // as expected
 TEST_F(DBBloomFilterTest, DynamicBloomFilterNewColumnFamily) {
  int iteration = 0;
-  for (bool use_block_based_builder : {true, false}) {
+  for (auto bfp_impl : BFP::kAllFixedImpls) {
    Options options = CurrentOptions();
    options.create_if_missing = true;
    options.prefix_extractor.reset(NewFixedPrefixTransform(1));
@@ -1607,8 +1779,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterNewColumnFamily) {
    // Enable prefix bloom for SST files
    BlockBasedTableOptions table_options;
    table_options.cache_index_and_filter_blocks = true;
-    table_options.filter_policy.reset(
-        NewBloomFilterPolicy(10, use_block_based_builder));
+    table_options.filter_policy.reset(new BFP(10, bfp_impl));
    options.table_factory.reset(NewBlockBasedTableFactory(table_options));
    CreateAndReopenWithCF({"pikachu" + std::to_string(iteration)}, options);
    ReadOptions read_options;
@@ -1657,8 +1828,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterNewColumnFamily) {
 // Verify it's possible to change prefix_extractor at runtime and iterators
 // behaves as expected
 TEST_F(DBBloomFilterTest, DynamicBloomFilterOptions) {
-  int iteration = 0;
-  for (bool use_block_based_builder : {true, false}) {
+  for (auto bfp_impl : BFP::kAllFixedImpls) {
    Options options;
    options.create_if_missing = true;
    options.prefix_extractor.reset(NewFixedPrefixTransform(1));
@@ -1667,8 +1837,7 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterOptions) {
    // Enable prefix bloom for SST files
    BlockBasedTableOptions table_options;
    table_options.cache_index_and_filter_blocks = true;
-    table_options.filter_policy.reset(
-        NewBloomFilterPolicy(10, use_block_based_builder));
+    table_options.filter_policy.reset(new BFP(10, bfp_impl));
    options.table_factory.reset(NewBlockBasedTableFactory(table_options));
    DestroyAndReopen(options);

@@ -1719,7 +1888,6 @@ TEST_F(DBBloomFilterTest, DynamicBloomFilterOptions) {
    ASSERT_EQ(CountIter(iter_old, "abc"), 0);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_CHECKED), 12);
    ASSERT_EQ(TestGetTickerCount(options, BLOOM_FILTER_PREFIX_USEFUL), 3);
-    iteration++;
  }
 }

@@ -720,7 +720,7 @@ TEST_F(DBTestCompactionFilter, CompactionFilterIgnoreSnapshot) {
  cfilter_count = 0;
  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
  // The filter should delete 40 records.
-  ASSERT_EQ(40U, cfilter_count);
+  ASSERT_EQ(40, cfilter_count);

  {
    // Scan the entire database as of the snapshot to ensure
@@ -12,6 +12,7 @@
 #include "port/stack_trace.h"
 #include "rocksdb/concurrent_task_limiter.h"
 #include "rocksdb/experimental.h"
+#include "rocksdb/sst_file_writer.h"
 #include "rocksdb/utilities/convenience.h"
 #include "test_util/fault_injection_test_env.h"
 #include "test_util/sync_point.h"
@@ -141,7 +142,7 @@ Options DeletionTriggerOptions(Options options) {
  options.compression = kNoCompression;
  options.write_buffer_size = kCDTKeysPerBuffer * (kCDTValueSize + 24);
  options.min_write_buffer_number_to_merge = 1;
-  options.max_write_buffer_number_to_maintain = 0;
+  options.max_write_buffer_size_to_maintain = 0;
  options.num_levels = kCDTNumLevels;
  options.level0_file_num_compaction_trigger = 1;
  options.target_file_size_base = options.write_buffer_size * 2;
@@ -732,7 +733,7 @@ TEST_F(DBCompactionTest, BGCompactionsAllowed) {

  // Now all column families qualify compaction but only one should be
  // scheduled, because no column family hits speed up condition.
-  ASSERT_EQ(1, env_->GetThreadPoolQueueLen(Env::Priority::LOW));
+  ASSERT_EQ(1u, env_->GetThreadPoolQueueLen(Env::Priority::LOW));

  // Create two more files for one column family, which triggers speed up
  // condition, three compactions will be scheduled.
@@ -746,7 +747,7 @@ TEST_F(DBCompactionTest, BGCompactionsAllowed) {
    ASSERT_EQ(options.level0_file_num_compaction_trigger + num + 1,
              NumTableFilesAtLevel(0, 2));
  }
-  ASSERT_EQ(3, env_->GetThreadPoolQueueLen(Env::Priority::LOW));
+  ASSERT_EQ(3U, env_->GetThreadPoolQueueLen(Env::Priority::LOW));

  // Unblock all threads to unblock all compactions.
  for (size_t i = 0; i < kTotalTasks; i++) {
@@ -777,7 +778,7 @@ TEST_F(DBCompactionTest, BGCompactionsAllowed) {

  // Now all column families qualify compaction but only one should be
  // scheduled, because no column family hits speed up condition.
-  ASSERT_EQ(1, env_->GetThreadPoolQueueLen(Env::Priority::LOW));
+  ASSERT_EQ(1U, env_->GetThreadPoolQueueLen(Env::Priority::LOW));

  for (size_t i = 0; i < kTotalTasks; i++) {
    sleeping_tasks[i].WakeUp();
@@ -1502,6 +1503,37 @@ TEST_F(DBCompactionTest, DISABLED_ManualPartialFill) {
  }
 }

+TEST_F(DBCompactionTest, ManualCompactionWithUnorderedWrite) {
+  rocksdb::SyncPoint::GetInstance()->LoadDependency(
+      {{"DBImpl::WriteImpl:UnorderedWriteAfterWriteWAL",
+        "DBCompactionTest::ManualCompactionWithUnorderedWrite:WaitWriteWAL"},
+       {"DBImpl::WaitForPendingWrites:BeforeBlock",
+        "DBImpl::WriteImpl:BeforeUnorderedWriteMemtable"}});
+
+  Options options = CurrentOptions();
+  options.unordered_write = true;
+  DestroyAndReopen(options);
+  Put("foo", "v1");
+  ASSERT_OK(Flush());
+
+  Put("bar", "v1");
+  rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+  port::Thread writer([&]() { Put("foo", "v2"); });
+
+  TEST_SYNC_POINT(
+      "DBCompactionTest::ManualCompactionWithUnorderedWrite:WaitWriteWAL");
+  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
+
+  writer.join();
+  ASSERT_EQ(Get("foo"), "v2");
+
+  SyncPoint::GetInstance()->DisableProcessing();
+  SyncPoint::GetInstance()->ClearAllCallBacks();
+
+  Reopen(options);
+  ASSERT_EQ(Get("foo"), "v2");
+}
+
 TEST_F(DBCompactionTest, DeleteFileRange) {
  Options options = CurrentOptions();
  options.write_buffer_size = 10 * 1024 * 1024;
@@ -3521,76 +3553,238 @@ TEST_F(DBCompactionTest, LevelCompactExpiredTtlFiles) {
  rocksdb::SyncPoint::GetInstance()->DisableProcessing();
 }

+TEST_F(DBCompactionTest, LevelTtlCascadingCompactions) {
+  const int kValueSize = 100;
+
+  for (bool if_restart : {false, true}) {
+    for (bool if_open_all_files : {false, true}) {
+      Options options = CurrentOptions();
+      options.compression = kNoCompression;
+      options.ttl = 24 * 60 * 60;  // 24 hours
+      if (if_open_all_files) {
+        options.max_open_files = -1;
+      } else {
+        options.max_open_files = 20;
+      }
+      // RocksDB sanitize max open files to at least 20. Modify it back.
+      rocksdb::SyncPoint::GetInstance()->SetCallBack(
+          "SanitizeOptions::AfterChangeMaxOpenFiles", [&](void* arg) {
+            int* max_open_files = static_cast<int*>(arg);
+            *max_open_files = 2;
+          });
+      // In the case where all files are opened and doing DB restart
+      // forcing the oldest ancester time in manifest file to be 0 to
+      // simulate the case of reading from an old version.
+      rocksdb::SyncPoint::GetInstance()->SetCallBack(
+          "VersionEdit::EncodeTo:VarintOldestAncesterTime", [&](void* arg) {
+            if (if_restart && if_open_all_files) {
+              std::string* encoded_fieled = static_cast<std::string*>(arg);
+              *encoded_fieled = "";
+              PutVarint64(encoded_fieled, 0);
+            }
+          });
+
+      env_->time_elapse_only_sleep_ = false;
+      options.env = env_;
+
+      env_->addon_time_.store(0);
+      DestroyAndReopen(options);
+
+      int ttl_compactions = 0;
+      rocksdb::SyncPoint::GetInstance()->SetCallBack(
+          "LevelCompactionPicker::PickCompaction:Return", [&](void* arg) {
+            Compaction* compaction = reinterpret_cast<Compaction*>(arg);
+            auto compaction_reason = compaction->compaction_reason();
+            if (compaction_reason == CompactionReason::kTtl) {
+              ttl_compactions++;
+            }
+          });
+      rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+
+      // Add two L6 files with key ranges: [1 .. 100], [101 .. 200].
+      Random rnd(301);
+      for (int i = 1; i <= 100; ++i) {
+        ASSERT_OK(Put(Key(i), RandomString(&rnd, kValueSize)));
+      }
+      Flush();
+      for (int i = 101; i <= 200; ++i) {
+        ASSERT_OK(Put(Key(i), RandomString(&rnd, kValueSize)));
+      }
+      Flush();
+      MoveFilesToLevel(6);
+      ASSERT_EQ("0,0,0,0,0,0,2", FilesPerLevel());
+
+      // Add two L4 files with key ranges: [1 .. 50], [51 .. 150].
+      for (int i = 1; i <= 50; ++i) {
+        ASSERT_OK(Put(Key(i), RandomString(&rnd, kValueSize)));
+      }
+      Flush();
+      for (int i = 51; i <= 150; ++i) {
+        ASSERT_OK(Put(Key(i), RandomString(&rnd, kValueSize)));
+      }
+      Flush();
+      MoveFilesToLevel(4);
+      ASSERT_EQ("0,0,0,0,2,0,2", FilesPerLevel());
+
+      // Add one L1 file with key range: [26, 75].
+      for (int i = 26; i <= 75; ++i) {
+        ASSERT_OK(Put(Key(i), RandomString(&rnd, kValueSize)));
+      }
+      Flush();
+      dbfull()->TEST_WaitForCompact();
+      MoveFilesToLevel(1);
+      ASSERT_EQ("0,1,0,0,2,0,2", FilesPerLevel());
+
+      // LSM tree:
+      // L1:         [26 .. 75]
+      // L4:     [1 .. 50][51 ..... 150]
+      // L6:     [1 ........ 100][101 .... 200]
+      //
+      // On TTL expiry, TTL compaction should be initiated on L1 file, and the
+      // compactions should keep going on until the key range hits bottom level.
+      // In other words: the compaction on this data range "cascasdes" until
+      // reaching the bottom level.
+      //
+      // Order of events on TTL expiry:
+      // 1. L1 file falls to L3 via 2 trivial moves which are initiated by the
+      // ttl
+      //    compaction.
+      // 2. A TTL compaction happens between L3 and L4 files. Output file in L4.
+      // 3. The new output file from L4 falls to L5 via 1 trival move initiated
+      //    by the ttl compaction.
+      // 4. A TTL compaction happens between L5 and L6 files. Ouptut in L6.
+
+      // Add 25 hours and do a write
+      env_->addon_time_.fetch_add(25 * 60 * 60);
+
+      ASSERT_OK(Put(Key(1), "1"));
+      if (if_restart) {
+        Reopen(options);
+      } else {
+        Flush();
+      }
+      dbfull()->TEST_WaitForCompact();
+      ASSERT_EQ("1,0,0,0,0,0,1", FilesPerLevel());
+      ASSERT_EQ(5, ttl_compactions);
+
+      env_->addon_time_.fetch_add(25 * 60 * 60);
+      ASSERT_OK(Put(Key(2), "1"));
+      if (if_restart) {
+        Reopen(options);
+      } else {
+        Flush();
+      }
+      dbfull()->TEST_WaitForCompact();
+      ASSERT_EQ("1,0,0,0,0,0,1", FilesPerLevel());
+      ASSERT_GE(ttl_compactions, 6);
+
+      rocksdb::SyncPoint::GetInstance()->DisableProcessing();
+    }
+  }
+}
+
 TEST_F(DBCompactionTest, LevelPeriodicCompaction) {
  const int kNumKeysPerFile = 32;
  const int kNumLevelFiles = 2;
  const int kValueSize = 100;

-  Options options = CurrentOptions();
-  options.periodic_compaction_seconds = 48 * 60 * 60;  // 2 days
-  options.max_open_files = -1;       // needed for ttl compaction
-  env_->time_elapse_only_sleep_ = false;
-  options.env = env_;
+  for (bool if_restart : {false, true}) {
+    for (bool if_open_all_files : {false, true}) {
+      Options options = CurrentOptions();
+      options.periodic_compaction_seconds = 48 * 60 * 60;  // 2 days
+      if (if_open_all_files) {
+        options.max_open_files = -1;  // needed for ttl compaction
+      } else {
+        options.max_open_files = 20;
+      }
+      // RocksDB sanitize max open files to at least 20. Modify it back.
+      rocksdb::SyncPoint::GetInstance()->SetCallBack(
+          "SanitizeOptions::AfterChangeMaxOpenFiles", [&](void* arg) {
+            int* max_open_files = static_cast<int*>(arg);
+            *max_open_files = 0;
+          });
+      // In the case where all files are opened and doing DB restart
+      // forcing the file creation time in manifest file to be 0 to
+      // simulate the case of reading from an old version.
+      rocksdb::SyncPoint::GetInstance()->SetCallBack(
+          "VersionEdit::EncodeTo:VarintFileCreationTime", [&](void* arg) {
+            if (if_restart && if_open_all_files) {
+              std::string* encoded_fieled = static_cast<std::string*>(arg);
+              *encoded_fieled = "";
+              PutVarint64(encoded_fieled, 0);
+            }
+          });

-  env_->addon_time_.store(0);
-  DestroyAndReopen(options);
+      env_->time_elapse_only_sleep_ = false;
+      options.env = env_;

-  int periodic_compactions = 0;
-  rocksdb::SyncPoint::GetInstance()->SetCallBack(
-      "LevelCompactionPicker::PickCompaction:Return", [&](void* arg) {
-        Compaction* compaction = reinterpret_cast<Compaction*>(arg);
-        auto compaction_reason = compaction->compaction_reason();
-        if (compaction_reason == CompactionReason::kPeriodicCompaction) {
-          periodic_compactions++;
+      env_->addon_time_.store(0);
+      DestroyAndReopen(options);
+
+      int periodic_compactions = 0;
+      rocksdb::SyncPoint::GetInstance()->SetCallBack(
+          "LevelCompactionPicker::PickCompaction:Return", [&](void* arg) {
+            Compaction* compaction = reinterpret_cast<Compaction*>(arg);
+            auto compaction_reason = compaction->compaction_reason();
+            if (compaction_reason == CompactionReason::kPeriodicCompaction) {
+              periodic_compactions++;
+            }
+          });
+      rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+
+      Random rnd(301);
+      for (int i = 0; i < kNumLevelFiles; ++i) {
+        for (int j = 0; j < kNumKeysPerFile; ++j) {
+          ASSERT_OK(Put(Key(i * kNumKeysPerFile + j),
+                        RandomString(&rnd, kValueSize)));
        }
-      });
-  rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+        Flush();
+      }
+      dbfull()->TEST_WaitForCompact();

-  Random rnd(301);
-  for (int i = 0; i < kNumLevelFiles; ++i) {
-    for (int j = 0; j < kNumKeysPerFile; ++j) {
-      ASSERT_OK(
-          Put(Key(i * kNumKeysPerFile + j), RandomString(&rnd, kValueSize)));
+      ASSERT_EQ("2", FilesPerLevel());
+      ASSERT_EQ(0, periodic_compactions);
+
+      // Add 50 hours and do a write
+      env_->addon_time_.fetch_add(50 * 60 * 60);
+      ASSERT_OK(Put("a", "1"));
+      Flush();
+      dbfull()->TEST_WaitForCompact();
+      // Assert that the files stay in the same level
+      ASSERT_EQ("3", FilesPerLevel());
+      // The two old files go through the periodic compaction process
+      ASSERT_EQ(2, periodic_compactions);
+
+      MoveFilesToLevel(1);
+      ASSERT_EQ("0,3", FilesPerLevel());
+
+      // Add another 50 hours and do another write
+      env_->addon_time_.fetch_add(50 * 60 * 60);
+      ASSERT_OK(Put("b", "2"));
+      if (if_restart) {
+        Reopen(options);
+      } else {
+        Flush();
+      }
+      dbfull()->TEST_WaitForCompact();
+      ASSERT_EQ("1,3", FilesPerLevel());
+      // The three old files now go through the periodic compaction process. 2
+      // + 3.
+      ASSERT_EQ(5, periodic_compactions);
+
+      // Add another 50 hours and do another write
+      env_->addon_time_.fetch_add(50 * 60 * 60);
+      ASSERT_OK(Put("c", "3"));
+      Flush();
+      dbfull()->TEST_WaitForCompact();
+      ASSERT_EQ("2,3", FilesPerLevel());
+      // The four old files now go through the periodic compaction process. 5
+      // + 4.
+      ASSERT_EQ(9, periodic_compactions);
+
+      rocksdb::SyncPoint::GetInstance()->DisableProcessing();
    }
-    Flush();
  }
-  dbfull()->TEST_WaitForCompact();
-
-  ASSERT_EQ("2", FilesPerLevel());
-  ASSERT_EQ(0, periodic_compactions);
-
-  // Add 50 hours and do a write
-  env_->addon_time_.fetch_add(50 * 60 * 60);
-  ASSERT_OK(Put("a", "1"));
-  Flush();
-  dbfull()->TEST_WaitForCompact();
-  // Assert that the files stay in the same level
-  ASSERT_EQ("3", FilesPerLevel());
-  // The two old files go through the periodic compaction process
-  ASSERT_EQ(2, periodic_compactions);
-
-  MoveFilesToLevel(1);
-  ASSERT_EQ("0,3", FilesPerLevel());
-
-  // Add another 50 hours and do another write
-  env_->addon_time_.fetch_add(50 * 60 * 60);
-  ASSERT_OK(Put("b", "2"));
-  Flush();
-  dbfull()->TEST_WaitForCompact();
-  ASSERT_EQ("1,3", FilesPerLevel());
-  // The three old files now go through the periodic compaction process. 2 + 3.
-  ASSERT_EQ(5, periodic_compactions);
-
-  // Add another 50 hours and do another write
-  env_->addon_time_.fetch_add(50 * 60 * 60);
-  ASSERT_OK(Put("c", "3"));
-  Flush();
-  dbfull()->TEST_WaitForCompact();
-  ASSERT_EQ("2,3", FilesPerLevel());
-  // The four old files now go through the periodic compaction process. 5 + 4.
-  ASSERT_EQ(9, periodic_compactions);
-
-  rocksdb::SyncPoint::GetInstance()->DisableProcessing();
 }

 TEST_F(DBCompactionTest, LevelPeriodicCompactionWithOldDB) {
@@ -3603,7 +3797,6 @@ TEST_F(DBCompactionTest, LevelPeriodicCompactionWithOldDB) {
  const int kValueSize = 100;

  Options options = CurrentOptions();
-  options.max_open_files = -1;  // needed for ttl compaction
  env_->time_elapse_only_sleep_ = false;
  options.env = env_;

@@ -3748,6 +3941,91 @@ TEST_F(DBCompactionTest, LevelPeriodicAndTtlCompaction) {
  rocksdb::SyncPoint::GetInstance()->DisableProcessing();
 }

+TEST_F(DBCompactionTest, LevelPeriodicCompactionWithCompactionFilters) {
+  class TestCompactionFilter : public CompactionFilter {
+    const char* Name() const override { return "TestCompactionFilter"; }
+  };
+  class TestCompactionFilterFactory : public CompactionFilterFactory {
+    const char* Name() const override { return "TestCompactionFilterFactory"; }
+    std::unique_ptr<CompactionFilter> CreateCompactionFilter(
+        const CompactionFilter::Context& /*context*/) override {
+      return std::unique_ptr<CompactionFilter>(new TestCompactionFilter());
+    }
+  };
+
+  const int kNumKeysPerFile = 32;
+  const int kNumLevelFiles = 2;
+  const int kValueSize = 100;
+
+  Random rnd(301);
+
+  Options options = CurrentOptions();
+  TestCompactionFilter test_compaction_filter;
+  env_->time_elapse_only_sleep_ = false;
+  options.env = env_;
+  env_->addon_time_.store(0);
+
+  enum CompactionFilterType {
+    kUseCompactionFilter,
+    kUseCompactionFilterFactory
+  };
+
+  for (CompactionFilterType comp_filter_type :
+       {kUseCompactionFilter, kUseCompactionFilterFactory}) {
+    // Assert that periodic compactions are not enabled.
+    ASSERT_EQ(port::kMaxUint64 - 1, options.periodic_compaction_seconds);
+
+    if (comp_filter_type == kUseCompactionFilter) {
+      options.compaction_filter = &test_compaction_filter;
+      options.compaction_filter_factory.reset();
+    } else if (comp_filter_type == kUseCompactionFilterFactory) {
+      options.compaction_filter = nullptr;
+      options.compaction_filter_factory.reset(
+          new TestCompactionFilterFactory());
+    }
+    DestroyAndReopen(options);
+
+    // periodic_compaction_seconds should be set to the sanitized value when
+    // a compaction filter or a compaction filter factory is used.
+    ASSERT_EQ(30 * 24 * 60 * 60,
+              dbfull()->GetOptions().periodic_compaction_seconds);
+
+    int periodic_compactions = 0;
+    rocksdb::SyncPoint::GetInstance()->SetCallBack(
+        "LevelCompactionPicker::PickCompaction:Return", [&](void* arg) {
+          Compaction* compaction = reinterpret_cast<Compaction*>(arg);
+          auto compaction_reason = compaction->compaction_reason();
+          if (compaction_reason == CompactionReason::kPeriodicCompaction) {
+            periodic_compactions++;
+          }
+        });
+    rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+
+    for (int i = 0; i < kNumLevelFiles; ++i) {
+      for (int j = 0; j < kNumKeysPerFile; ++j) {
+        ASSERT_OK(
+            Put(Key(i * kNumKeysPerFile + j), RandomString(&rnd, kValueSize)));
+      }
+      Flush();
+    }
+    dbfull()->TEST_WaitForCompact();
+
+    ASSERT_EQ("2", FilesPerLevel());
+    ASSERT_EQ(0, periodic_compactions);
+
+    // Add 31 days and do a write
+    env_->addon_time_.fetch_add(31 * 24 * 60 * 60);
+    ASSERT_OK(Put("a", "1"));
+    Flush();
+    dbfull()->TEST_WaitForCompact();
+    // Assert that the files stay in the same level
+    ASSERT_EQ("3", FilesPerLevel());
+    // The two old files go through the periodic compaction process
+    ASSERT_EQ(2, periodic_compactions);
+
+    rocksdb::SyncPoint::GetInstance()->DisableProcessing();
+  }
+}

 TEST_F(DBCompactionTest, CompactRangeDelayedByL0FileCount) {
  // Verify that, when `CompactRangeOptions::allow_write_stall == false`, manual
@@ -4165,7 +4443,7 @@ TEST_F(DBCompactionTest, CompactionLimiter) {

  const char* cf_names[] = {"default", "0", "1", "2", "3", "4", "5",
    "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
-  const int cf_count = sizeof cf_names / sizeof cf_names[0];
+  const unsigned int cf_count = sizeof cf_names / sizeof cf_names[0];

  std::unordered_map<std::string, CompactionLimiter*> cf_to_limiter;

@@ -4184,7 +4462,7 @@ TEST_F(DBCompactionTest, CompactionLimiter) {
  std::vector<Options> option_vector;
  option_vector.reserve(cf_count);

-  for (int cf = 0; cf < cf_count; cf++) {
+  for (unsigned int cf = 0; cf < cf_count; cf++) {
    ColumnFamilyOptions cf_opt(options);
    if (cf == 0) {
      // "Default" CF does't use compaction limiter
@@ -4202,7 +4480,7 @@ TEST_F(DBCompactionTest, CompactionLimiter) {
    option_vector.emplace_back(DBOptions(options), cf_opt);
  }

-  for (int cf = 1; cf < cf_count; cf++) {
+  for (unsigned int cf = 1; cf < cf_count; cf++) {
    CreateColumnFamilies({cf_names[cf]}, option_vector[cf]);
  }

@@ -4254,7 +4532,7 @@ TEST_F(DBCompactionTest, CompactionLimiter) {
  int keyIndex = 0;

  for (int n = 0; n < options.level0_file_num_compaction_trigger; n++) {
-    for (int cf = 0; cf < cf_count; cf++) {
+    for (unsigned int cf = 0; cf < cf_count; cf++) {
      for (int i = 0; i < kNumKeysPerFile; i++) {
        ASSERT_OK(Put(cf, Key(keyIndex++), ""));
      }
@@ -4262,13 +4540,13 @@ TEST_F(DBCompactionTest, CompactionLimiter) {
      ASSERT_OK(Put(cf, "", ""));
    }

-    for (int cf = 0; cf < cf_count; cf++) {
+    for (unsigned int cf = 0; cf < cf_count; cf++) {
      dbfull()->TEST_WaitForFlushMemTable(handles_[cf]);
    }
  }

  // Enough L0 files to trigger compaction
-  for (int cf = 0; cf < cf_count; cf++) {
+  for (unsigned int cf = 0; cf < cf_count; cf++) {
    ASSERT_EQ(NumTableFilesAtLevel(0, cf),
      options.level0_file_num_compaction_trigger);
  }
@@ -4295,7 +4573,7 @@ TEST_F(DBCompactionTest, CompactionLimiter) {
    sleeping_compact_tasks[i].WaitUntilDone();
  }

-  for (int cf = 0; cf < cf_count; cf++) {
+  for (unsigned int cf = 0; cf < cf_count; cf++) {
    dbfull()->TEST_WaitForFlushMemTable(handles_[cf]);
  }

@@ -4659,6 +4937,201 @@ TEST_P(DBCompactionTestWithParam, FixFileIngestionCompactionDeadlock) {
  Close();
 }

+TEST_F(DBCompactionTest, ConsistencyFailTest) {
+  Options options = CurrentOptions();
+  DestroyAndReopen(options);
+
+  rocksdb::SyncPoint::GetInstance()->SetCallBack(
+      "VersionBuilder::CheckConsistency", [&](void* arg) {
+        auto p =
+            reinterpret_cast<std::pair<FileMetaData**, FileMetaData**>*>(arg);
+        // just swap the two FileMetaData so that we hit error
+        // in CheckConsistency funcion
+        FileMetaData* temp = *(p->first);
+        *(p->first) = *(p->second);
+        *(p->second) = temp;
+      });
+
+  rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+
+  for (int k = 0; k < 2; ++k) {
+    ASSERT_OK(Put("foo", "bar"));
+    Flush();
+  }
+
+  ASSERT_NOK(Put("foo", "bar"));
+  rocksdb::SyncPoint::GetInstance()->DisableProcessing();
+}
+
+void IngestOneKeyValue(DBImpl* db, const std::string& key,
+                       const std::string& value, const Options& options) {
+  ExternalSstFileInfo info;
+  std::string f = test::PerThreadDBPath("sst_file" + key);
+  EnvOptions env;
+  rocksdb::SstFileWriter writer(env, options);
+  auto s = writer.Open(f);
+  ASSERT_OK(s);
+  // ASSERT_OK(writer.Put(Key(), ""));
+  ASSERT_OK(writer.Put(key, value));
+
+  ASSERT_OK(writer.Finish(&info));
+  IngestExternalFileOptions ingest_opt;
+
+  ASSERT_OK(db->IngestExternalFile({info.file_path}, ingest_opt));
+}
+
+TEST_P(DBCompactionTestWithParam,
+       FlushAfterIntraL0CompactionCheckConsistencyFail) {
+  Options options = CurrentOptions();
+  options.force_consistency_checks = true;
+  options.compression = kNoCompression;
+  options.level0_file_num_compaction_trigger = 5;
+  options.max_background_compactions = 2;
+  options.max_subcompactions = max_subcompactions_;
+  DestroyAndReopen(options);
+
+  const size_t kValueSize = 1 << 20;
+  Random rnd(301);
+  std::atomic<int> pick_intra_l0_count(0);
+  std::string value(RandomString(&rnd, kValueSize));
+
+  rocksdb::SyncPoint::GetInstance()->LoadDependency(
+      {{"DBCompactionTestWithParam::FlushAfterIntraL0:1",
+        "CompactionJob::Run():Start"}});
+  rocksdb::SyncPoint::GetInstance()->SetCallBack(
+      "FindIntraL0Compaction",
+      [&](void* /*arg*/) { pick_intra_l0_count.fetch_add(1); });
+
+  rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+
+  // prevents trivial move
+  for (int i = 0; i < 10; ++i) {
+    ASSERT_OK(Put(Key(i), ""));  // prevents trivial move
+  }
+  ASSERT_OK(Flush());
+  Compact("", Key(99));
+  ASSERT_EQ(0, NumTableFilesAtLevel(0));
+
+  // Flush 5 L0 sst.
+  for (int i = 0; i < 5; ++i) {
+    ASSERT_OK(Put(Key(i + 1), value));
+    ASSERT_OK(Flush());
+  }
+  ASSERT_EQ(5, NumTableFilesAtLevel(0));
+
+  // Put one key, to make smallest log sequence number in this memtable is less
+  // than sst which would be ingested in next step.
+  ASSERT_OK(Put(Key(0), "a"));
+
+  ASSERT_EQ(5, NumTableFilesAtLevel(0));
+
+  // Ingest 5 L0 sst. And this files would trigger PickIntraL0Compaction.
+  for (int i = 5; i < 10; i++) {
+    IngestOneKeyValue(dbfull(), Key(i), value, options);
+    ASSERT_EQ(i + 1, NumTableFilesAtLevel(0));
+  }
+
+  TEST_SYNC_POINT("DBCompactionTestWithParam::FlushAfterIntraL0:1");
+  // Put one key, to make biggest log sequence number in this memtable is bigger
+  // than sst which would be ingested in next step.
+  ASSERT_OK(Put(Key(2), "b"));
+  ASSERT_EQ(10, NumTableFilesAtLevel(0));
+  dbfull()->TEST_WaitForCompact();
+  rocksdb::SyncPoint::GetInstance()->DisableProcessing();
+  std::vector<std::vector<FileMetaData>> level_to_files;
+  dbfull()->TEST_GetFilesMetaData(dbfull()->DefaultColumnFamily(),
+                                  &level_to_files);
+  ASSERT_GT(level_to_files[0].size(), 0);
+  ASSERT_GT(pick_intra_l0_count.load(), 0);
+
+  ASSERT_OK(Flush());
+}
+
+TEST_P(DBCompactionTestWithParam,
+       IntraL0CompactionAfterFlushCheckConsistencyFail) {
+  Options options = CurrentOptions();
+  options.force_consistency_checks = true;
+  options.compression = kNoCompression;
+  options.level0_file_num_compaction_trigger = 5;
+  options.max_background_compactions = 2;
+  options.max_subcompactions = max_subcompactions_;
+  options.write_buffer_size = 2 << 20;
+  options.max_write_buffer_number = 6;
+  DestroyAndReopen(options);
+
+  const size_t kValueSize = 1 << 20;
+  Random rnd(301);
+  std::string value(RandomString(&rnd, kValueSize));
+  std::string value2(RandomString(&rnd, kValueSize));
+  std::string bigvalue = value + value;
+
+  // prevents trivial move
+  for (int i = 0; i < 10; ++i) {
+    ASSERT_OK(Put(Key(i), ""));  // prevents trivial move
+  }
+  ASSERT_OK(Flush());
+  Compact("", Key(99));
+  ASSERT_EQ(0, NumTableFilesAtLevel(0));
+
+  std::atomic<int> pick_intra_l0_count(0);
+  rocksdb::SyncPoint::GetInstance()->LoadDependency(
+      {{"DBCompactionTestWithParam::IntraL0CompactionAfterFlush:1",
+        "CompactionJob::Run():Start"}});
+  rocksdb::SyncPoint::GetInstance()->SetCallBack(
+      "FindIntraL0Compaction",
+      [&](void* /*arg*/) { pick_intra_l0_count.fetch_add(1); });
+  rocksdb::SyncPoint::GetInstance()->EnableProcessing();
+  // Make 6 L0 sst.
+  for (int i = 0; i < 6; ++i) {
+    if (i % 2 == 0) {
+      IngestOneKeyValue(dbfull(), Key(i), value, options);
+    } else {
+      ASSERT_OK(Put(Key(i), value));
+      ASSERT_OK(Flush());
+    }
+  }
+
+  ASSERT_EQ(6, NumTableFilesAtLevel(0));
+
+  // Stop run flush job
+  env_->SetBackgroundThreads(1, Env::HIGH);
+  test::SleepingBackgroundTask sleeping_tasks;
+  env_->Schedule(&test::SleepingBackgroundTask::DoSleepTask, &sleeping_tasks,
+                 Env::Priority::HIGH);
+  sleeping_tasks.WaitUntilSleeping();
+
+  // Put many keys to make memtable request to flush
+  for (int i = 0; i < 6; ++i) {
+    ASSERT_OK(Put(Key(i), bigvalue));
+  }
+
+  ASSERT_EQ(6, NumTableFilesAtLevel(0));
+  // ingest file to trigger IntraL0Compaction
+  for (int i = 6; i < 10; ++i) {
+    ASSERT_EQ(i, NumTableFilesAtLevel(0));
+    IngestOneKeyValue(dbfull(), Key(i), value2, options);
+  }
+  ASSERT_EQ(10, NumTableFilesAtLevel(0));
+
+  // Wake up flush job
+  sleeping_tasks.WakeUp();
+  sleeping_tasks.WaitUntilDone();
+  TEST_SYNC_POINT("DBCompactionTestWithParam::IntraL0CompactionAfterFlush:1");
+  dbfull()->TEST_WaitForCompact();
+  rocksdb::SyncPoint::GetInstance()->DisableProcessing();
+
+  uint64_t error_count = 0;
+  db_->GetIntProperty("rocksdb.background-errors", &error_count);
+  ASSERT_EQ(error_count, 0);
+  ASSERT_GT(pick_intra_l0_count.load(), 0);
+  for (int i = 0; i < 6; ++i) {
+    ASSERT_EQ(bigvalue, Get(Key(i)));
+  }
+  for (int i = 6; i < 10; ++i) {
+    ASSERT_EQ(value2, Get(Key(i)));
+  }
+}
+
 #endif // !defined(ROCKSDB_LITE)
 }  // namespace rocksdb

@@ -83,6 +83,34 @@ TEST_F(DBEncryptionTest, CheckEncrypted) {
  }
 }

+TEST_F(DBEncryptionTest, ReadEmptyFile) {
+  auto defaultEnv = Env::Default();
+
+  // create empty file for reading it back in later
+  auto envOptions = EnvOptions(CurrentOptions());
+  auto filePath = dbname_ + "/empty.empty";
+
+  Status status;
+  {
+    std::unique_ptr<WritableFile> writableFile;
+    status = defaultEnv->NewWritableFile(filePath, &writableFile, envOptions);
+    ASSERT_OK(status);
+  }
+
+  std::unique_ptr<SequentialFile> seqFile;
+  status = defaultEnv->NewSequentialFile(filePath, &seqFile, envOptions);
+  ASSERT_OK(status);
+
+  std::string scratch;
+  Slice data;
+  // reading back 16 bytes from the empty file shouldn't trigger an assertion.
+  // it should just work and return an empty string
+  status = seqFile->Read(16, &data, (char*)scratch.data());
+  ASSERT_OK(status);
+
+  ASSERT_TRUE(data.empty());
+}
+
 #endif // ROCKSDB_LITE

 }  // namespace rocksdb
@@ -6,9 +6,9 @@

 #ifndef ROCKSDB_LITE

-#include <cinttypes>
 #include <stdint.h>
 #include <algorithm>
+#include <cinttypes>
 #include <string>
 #include "db/db_impl/db_impl.h"
 #include "db/job_context.h"
@@ -102,7 +102,7 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
        TEST_SYNC_POINT("DBImpl::GetLiveFiles:1");
        TEST_SYNC_POINT("DBImpl::GetLiveFiles:2");
        mutex_.Lock();
-        cfd->Unref();
+        cfd->UnrefAndTryDelete();
        if (!status.ok()) {
          break;
        }
@@ -163,6 +163,15 @@ Status DBImpl::GetSortedWalFiles(VectorLogPtr& files) {
  return wal_manager_.GetSortedWalFiles(files);
 }

+Status DBImpl::GetCurrentWalFile(std::unique_ptr<LogFile>* current_log_file) {
+  uint64_t current_logfile_number;
+  {
+    InstrumentedMutexLock l(&mutex_);
+    current_logfile_number = logfile_number_;
+  }
+
+  return wal_manager_.GetLiveWalFile(current_logfile_number, current_log_file);
+}
 }

 #endif  // ROCKSDB_LITE
@@ -7,10 +7,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

+#include <atomic>
+
+#include "db/db_impl/db_impl.h"
 #include "db/db_test_util.h"
+#include "port/port.h"
 #include "port/stack_trace.h"
 #include "test_util/fault_injection_test_env.h"
 #include "test_util/sync_point.h"
+#include "util/cast_util.h"
+#include "util/mutexlock.h"

 namespace rocksdb {

@@ -206,6 +212,30 @@ TEST_F(DBFlushTest, ManualFlushWithMinWriteBufferNumberToMerge) {
  t.join();
 }

+TEST_F(DBFlushTest, ScheduleOnlyOneBgThread) {
+  Options options = CurrentOptions();
+  Reopen(options);
+  SyncPoint::GetInstance()->DisableProcessing();
+  SyncPoint::GetInstance()->ClearAllCallBacks();
+  int called = 0;
+  SyncPoint::GetInstance()->SetCallBack(
+      "DBImpl::MaybeScheduleFlushOrCompaction:AfterSchedule:0", [&](void* arg) {
+        ASSERT_NE(nullptr, arg);
+        auto unscheduled_flushes = *reinterpret_cast<int*>(arg);
+        ASSERT_EQ(0, unscheduled_flushes);
+        ++called;
+      });
+  SyncPoint::GetInstance()->EnableProcessing();
+
+  ASSERT_OK(Put("a", "foo"));
+  FlushOptions flush_opts;
+  ASSERT_OK(dbfull()->Flush(flush_opts));
+  ASSERT_EQ(1, called);
+
+  SyncPoint::GetInstance()->DisableProcessing();
+  SyncPoint::GetInstance()->ClearAllCallBacks();
+}
+
 TEST_P(DBFlushDirectIOTest, DirectIO) {
  Options options;
  options.create_if_missing = true;
@@ -323,6 +353,96 @@ TEST_F(DBFlushTest, CFDropRaceWithWaitForFlushMemTables) {
  SyncPoint::GetInstance()->DisableProcessing();
 }

+#ifndef ROCKSDB_LITE
+TEST_F(DBFlushTest, FireOnFlushCompletedAfterCommittedResult) {
+  class TestListener : public EventListener {
+   public:
+    void OnFlushCompleted(DB* db, const FlushJobInfo& info) override {
+      // There's only one key in each flush.
+      ASSERT_EQ(info.smallest_seqno, info.largest_seqno);
+      ASSERT_NE(0, info.smallest_seqno);
+      if (info.smallest_seqno == seq1) {
+        // First flush completed
+        ASSERT_FALSE(completed1);
+        completed1 = true;
+        CheckFlushResultCommitted(db, seq1);
+      } else {
+        // Second flush completed
+        ASSERT_FALSE(completed2);
+        completed2 = true;
+        ASSERT_EQ(info.smallest_seqno, seq2);
+        CheckFlushResultCommitted(db, seq2);
+      }
+    }
+
+    void CheckFlushResultCommitted(DB* db, SequenceNumber seq) {
+      DBImpl* db_impl = static_cast_with_check<DBImpl>(db);
+      InstrumentedMutex* mutex = db_impl->mutex();
+      mutex->Lock();
+      auto* cfd =
+          reinterpret_cast<ColumnFamilyHandleImpl*>(db->DefaultColumnFamily())
+              ->cfd();
+      ASSERT_LT(seq, cfd->imm()->current()->GetEarliestSequenceNumber());
+      mutex->Unlock();
+    }
+
+    std::atomic<SequenceNumber> seq1{0};
+    std::atomic<SequenceNumber> seq2{0};
+    std::atomic<bool> completed1{false};
+    std::atomic<bool> completed2{false};
+  };
+  std::shared_ptr<TestListener> listener = std::make_shared<TestListener>();
+
+  SyncPoint::GetInstance()->LoadDependency(
+      {{"DBImpl::BackgroundCallFlush:start",
+        "DBFlushTest::FireOnFlushCompletedAfterCommittedResult:WaitFirst"},
+       {"DBImpl::FlushMemTableToOutputFile:Finish",
+        "DBFlushTest::FireOnFlushCompletedAfterCommittedResult:WaitSecond"}});
+  SyncPoint::GetInstance()->SetCallBack(
+      "FlushJob::WriteLevel0Table", [&listener](void* arg) {
+        // Wait for the second flush finished, out of mutex.
+        auto* mems = reinterpret_cast<autovector<MemTable*>*>(arg);
+        if (mems->front()->GetEarliestSequenceNumber() == listener->seq1 - 1) {
+          TEST_SYNC_POINT(
+              "DBFlushTest::FireOnFlushCompletedAfterCommittedResult:"
+              "WaitSecond");
+        }
+      });
+
+  Options options = CurrentOptions();
+  options.create_if_missing = true;
+  options.listeners.push_back(listener);
+  // Setting max_flush_jobs = max_background_jobs / 4 = 2.
+  options.max_background_jobs = 8;
+  // Allow 2 immutable memtables.
+  options.max_write_buffer_number = 3;
+  Reopen(options);
+  SyncPoint::GetInstance()->EnableProcessing();
+  ASSERT_OK(Put("foo", "v"));
+  listener->seq1 = db_->GetLatestSequenceNumber();
+  // t1 will wait for the second flush complete before committing flush result.
+  auto t1 = port::Thread([&]() {
+    // flush_opts.wait = true
+    ASSERT_OK(db_->Flush(FlushOptions()));
+  });
+  // Wait for first flush started.
+  TEST_SYNC_POINT(
+      "DBFlushTest::FireOnFlushCompletedAfterCommittedResult:WaitFirst");
+  // The second flush will exit early without commit its result. The work
+  // is delegated to the first flush.
+  ASSERT_OK(Put("bar", "v"));
+  listener->seq2 = db_->GetLatestSequenceNumber();
+  FlushOptions flush_opts;
+  flush_opts.wait = false;
+  ASSERT_OK(db_->Flush(flush_opts));
+  t1.join();
+  ASSERT_TRUE(listener->completed1);
+  ASSERT_TRUE(listener->completed2);
+  SyncPoint::GetInstance()->DisableProcessing();
+  SyncPoint::GetInstance()->ClearAllCallBacks();
+}
+#endif  // !ROCKSDB_LITE
+
 TEST_P(DBAtomicFlushTest, ManualAtomicFlush) {
  Options options = CurrentOptions();
  options.create_if_missing = true;
@@ -37,6 +37,7 @@
 #include "db/read_callback.h"
 #include "db/snapshot_checker.h"
 #include "db/snapshot_impl.h"
+#include "db/trim_history_scheduler.h"
 #include "db/version_edit.h"
 #include "db/wal_manager.h"
 #include "db/write_controller.h"
@@ -127,6 +128,10 @@ class DBImpl : public DB {
 public:
  DBImpl(const DBOptions& options, const std::string& dbname,
         const bool seq_per_batch = false, const bool batch_per_txn = true);
+  // No copying allowed
+  DBImpl(const DBImpl&) = delete;
+  void operator=(const DBImpl&) = delete;
+
  virtual ~DBImpl();

  // ---- Implementations of the DB interface ----
@@ -159,6 +164,21 @@ class DBImpl : public DB {
                     ColumnFamilyHandle* column_family, const Slice& key,
                     PinnableSlice* value) override;

+  using DB::GetMergeOperands;
+  Status GetMergeOperands(const ReadOptions& options,
+                          ColumnFamilyHandle* column_family, const Slice& key,
+                          PinnableSlice* merge_operands,
+                          GetMergeOperandsOptions* get_merge_operands_options,
+                          int* number_of_operands) override {
+    GetImplOptions get_impl_options;
+    get_impl_options.column_family = column_family;
+    get_impl_options.merge_operands = merge_operands;
+    get_impl_options.get_merge_operands_options = get_merge_operands_options;
+    get_impl_options.number_of_operands = number_of_operands;
+    get_impl_options.get_value = false;
+    return GetImpl(options, key, get_impl_options);
+  }
+
  using DB::MultiGet;
  virtual std::vector<Status> MultiGet(
      const ReadOptions& options,
@@ -179,11 +199,15 @@ class DBImpl : public DB {
                        PinnableSlice* values, Status* statuses,
                        const bool sorted_input = false) override;

-  void MultiGetImpl(
+  virtual void MultiGet(const ReadOptions& options, const size_t num_keys,
+                        ColumnFamilyHandle** column_families, const Slice* keys,
+                        PinnableSlice* values, Status* statuses,
+                        const bool sorted_input = false) override;
+
+  virtual void MultiGetWithCallback(
      const ReadOptions& options, ColumnFamilyHandle* column_family,
-      autovector<KeyContext, MultiGetContext::MAX_BATCH_SIZE>& key_context,
-      bool sorted_input, ReadCallback* callback = nullptr,
-      bool* is_blob_index = nullptr);
+      ReadCallback* callback,
+      autovector<KeyContext*, MultiGetContext::MAX_BATCH_SIZE>* sorted_keys);

  virtual Status CreateColumnFamily(const ColumnFamilyOptions& cf_options,
                                    const std::string& column_family,
@@ -262,6 +286,9 @@ class DBImpl : public DB {
  virtual Status EnableAutoCompaction(
      const std::vector<ColumnFamilyHandle*>& column_family_handles) override;

+  virtual void EnableManualCompaction() override;
+  virtual void DisableManualCompaction() override;
+
  using DB::SetOptions;
  Status SetOptions(
      ColumnFamilyHandle* column_family,
@@ -279,6 +306,7 @@ class DBImpl : public DB {
      ColumnFamilyHandle* column_family) override;
  virtual const std::string& GetName() const override;
  virtual Env* GetEnv() const override;
+  virtual FileSystem* GetFileSystem() const override;
  using DB::GetOptions;
  virtual Options GetOptions(ColumnFamilyHandle* column_family) const override;
  using DB::GetDBOptions;
@@ -301,6 +329,8 @@ class DBImpl : public DB {

  virtual Status GetDbIdentity(std::string& identity) const override;

+  virtual Status GetDbIdentityFromIdentityFile(std::string* identity) const;
+
  ColumnFamilyHandle* DefaultColumnFamily() const override;

  ColumnFamilyHandle* PersistentStatsColumnFamily() const;
@@ -322,6 +352,10 @@ class DBImpl : public DB {
                              uint64_t* manifest_file_size,
                              bool flush_memtable = true) override;
  virtual Status GetSortedWalFiles(VectorLogPtr& files) override;
+  virtual Status GetCurrentWalFile(
+      std::unique_ptr<LogFile>* current_log_file) override;
+  virtual Status GetCreationTimeOfOldestFile(
+      uint64_t* creation_time) override;

  virtual Status GetUpdatesSince(
      SequenceNumber seq_number, std::unique_ptr<TransactionLogIterator>* iter,
@@ -365,7 +399,8 @@ class DBImpl : public DB {
      const ExportImportFilesMetaData& metadata,
      ColumnFamilyHandle** handle) override;

-  virtual Status VerifyChecksum() override;
+  using DB::VerifyChecksum;
+  virtual Status VerifyChecksum(const ReadOptions& /*read_options*/) override;

  using DB::StartTrace;
  virtual Status StartTrace(
@@ -395,12 +430,32 @@ class DBImpl : public DB {

  // ---- End of implementations of the DB interface ----

+  struct GetImplOptions {
+    ColumnFamilyHandle* column_family = nullptr;
+    PinnableSlice* value = nullptr;
+    bool* value_found = nullptr;
+    ReadCallback* callback = nullptr;
+    bool* is_blob_index = nullptr;
+    // If true return value associated with key via value pointer else return
+    // all merge operands for key via merge_operands pointer
+    bool get_value = true;
+    // Pointer to an array of size
+    // get_merge_operands_options.expected_max_number_of_operands allocated by
+    // user
+    PinnableSlice* merge_operands = nullptr;
+    GetMergeOperandsOptions* get_merge_operands_options = nullptr;
+    int* number_of_operands = nullptr;
+  };
+
  // Function that Get and KeyMayExist call with no_io true or false
  // Note: 'value_found' from KeyMayExist propagates here
-  Status GetImpl(const ReadOptions& options, ColumnFamilyHandle* column_family,
-                 const Slice& key, PinnableSlice* value,
-                 bool* value_found = nullptr, ReadCallback* callback = nullptr,
-                 bool* is_blob_index = nullptr);
+  // This function is also called by GetMergeOperands
+  // If get_impl_options.get_value = true get value associated with
+  // get_impl_options.key via get_impl_options.value
+  // If get_impl_options.get_value = false get merge operands associated with
+  // get_impl_options.key via get_impl_options.merge_operands
+  Status GetImpl(const ReadOptions& options, const Slice& key,
+                 GetImplOptions get_impl_options);

  ArenaWrappedDBIter* NewIteratorImpl(const ReadOptions& options,
                                      ColumnFamilyData* cfd,
@@ -744,6 +799,10 @@ class DBImpl : public DB {
    logs_to_free_queue_.push_back(log_writer);
  }

+  void AddSuperVersionsToFreeQueue(SuperVersion* sv) {
+    superversions_to_free_queue_.push_back(sv);
+  }
+
  void SetSnapshotChecker(SnapshotChecker* snapshot_checker);

  // Fill JobContext with snapshot information needed by flush and compaction.
@@ -777,6 +836,13 @@ class DBImpl : public DB {
                       uint64_t* new_time,
                       std::map<std::string, uint64_t>* stats_map);

+  // Print information of all tombstones of all iterators to the std::string
+  // This is only used by ldb. The output might be capped. Tombstones
+  // printed out are not guaranteed to be in any order.
+  Status TablesRangeTombstoneSummary(ColumnFamilyHandle* column_family,
+                                     int max_entries_to_print,
+                                     std::string* out_str);
+
 #ifndef NDEBUG
  // Compact any files in the named level that overlap [*begin, *end]
  Status TEST_CompactRange(int level, const Slice* begin, const Slice* end,
@@ -877,16 +943,17 @@ class DBImpl : public DB {
  void TEST_WaitForPersistStatsRun(std::function<void()> callback) const;
  bool TEST_IsPersistentStatsEnabled() const;
  size_t TEST_EstimateInMemoryStatsHistorySize() const;
-
 #endif  // NDEBUG

 protected:
-  Env* const env_;
  const std::string dbname_;
+  std::string db_id_;
  std::unique_ptr<VersionSet> versions_;
  // Flag to check whether we allocated and own the info log file
  bool own_info_log_;
  const DBOptions initial_db_options_;
+  Env* const env_;
+  std::shared_ptr<FileSystem> fs_;
  const ImmutableDBOptions immutable_db_options_;
  MutableDBOptions mutable_db_options_;
  Statistics* stats_;
@@ -914,10 +981,10 @@ class DBImpl : public DB {
  bool single_column_family_mode_;

  // The options to access storage files
-  const EnvOptions env_options_;
+  const FileOptions file_options_;

  // Additonal options for compaction and flush
-  EnvOptions env_options_for_compaction_;
+  FileOptions file_options_for_compaction_;

  std::unique_ptr<ColumnFamilyMemTablesImpl> column_family_memtables_;

@@ -950,11 +1017,11 @@ class DBImpl : public DB {

  void NotifyOnFlushBegin(ColumnFamilyData* cfd, FileMetaData* file_meta,
                          const MutableCFOptions& mutable_cf_options,
-                          int job_id, TableProperties prop);
+                          int job_id);

-  void NotifyOnFlushCompleted(ColumnFamilyData* cfd, FileMetaData* file_meta,
-                              const MutableCFOptions& mutable_cf_options,
-                              int job_id, TableProperties prop);
+  void NotifyOnFlushCompleted(
+      ColumnFamilyData* cfd, const MutableCFOptions& mutable_cf_options,
+      std::list<std::unique_ptr<FlushJobInfo>>* flush_jobs_info);

  void NotifyOnCompactionBegin(ColumnFamilyData* cfd, Compaction* c,
                               const Status& st,
@@ -1048,6 +1115,8 @@ class DBImpl : public DB {
      bool read_only = false, bool error_if_log_file_exist = false,
      bool error_if_data_exists_in_logs = false);

+  virtual bool OwnTablesAndLogs() const { return true; }
+
 private:
  friend class DB;
  friend class ErrorHandler;
@@ -1132,7 +1201,7 @@ class DBImpl : public DB {
  };

  // PurgeFileInfo is a structure to hold information of files to be deleted in
-  // purge_queue_
+  // purge_files_
  struct PurgeFileInfo {
    std::string fname;
    std::string dir_to_sync;
@@ -1258,7 +1327,8 @@ class DBImpl : public DB {
  // created between the calls CaptureCurrentFileNumberInPendingOutputs() and
  // ReleaseFileNumberFromPendingOutputs() can now be deleted (if it's not live
  // and blocked by any other pending_outputs_ calls)
-  void ReleaseFileNumberFromPendingOutputs(std::list<uint64_t>::iterator v);
+  void ReleaseFileNumberFromPendingOutputs(
+      std::unique_ptr<std::list<uint64_t>::iterator>& v);

  Status SyncClosedLogs(JobContext* job_context);

@@ -1313,6 +1383,8 @@ class DBImpl : public DB {

  void MaybeFlushStatsCF(autovector<ColumnFamilyData*>* cfds);

+  Status TrimMemtableHistory(WriteContext* context);
+
  Status SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context);

  void SelectColumnFamiliesForAtomicFlush(autovector<ColumnFamilyData*>* cfds);
@@ -1349,10 +1421,23 @@ class DBImpl : public DB {
      bool resuming_from_bg_err);

  inline void WaitForPendingWrites() {
+    mutex_.AssertHeld();
+    TEST_SYNC_POINT("DBImpl::WaitForPendingWrites:BeforeBlock");
+    // In case of pipelined write is enabled, wait for all pending memtable
+    // writers.
+    if (immutable_db_options_.enable_pipelined_write) {
+      // Memtable writers may call DB::Get in case max_successive_merges > 0,
+      // which may lock mutex. Unlocking mutex here to avoid deadlock.
+      mutex_.Unlock();
+      write_thread_.WaitForMemTableWriters();
+      mutex_.Lock();
+    }
+
    if (!immutable_db_options_.unordered_write) {
      // Then the writes are finished before the next write group starts
      return;
    }
+
    // Wait for the ones who already wrote to the WAL to finish their
    // memtable write.
    if (pending_memtable_writes_.load() != 0) {
@@ -1514,10 +1599,6 @@ class DBImpl : public DB {

  void WaitForBackgroundWork();

-  // No copying allowed
-  DBImpl(const DBImpl&);
-  void operator=(const DBImpl&);
-
  // Background threads call this function, which is just a wrapper around
  // the InstallSuperVersion() function. Background threads carry
  // sv_context which can have new_superversion already
@@ -1552,7 +1633,7 @@ class DBImpl : public DB {
  // Write a version edit to the MANIFEST.
  Status ReserveFileNumbersBeforeIngestion(
      ColumnFamilyData* cfd, uint64_t num,
-      std::list<uint64_t>::iterator* pending_output_elem,
+      std::unique_ptr<std::list<uint64_t>::iterator>& pending_output_elem,
      uint64_t* next_file_number);
 #endif  //! ROCKSDB_LITE

@@ -1572,6 +1653,81 @@ class DBImpl : public DB {
      const DBOptions& db_options,
      const std::vector<ColumnFamilyDescriptor>& column_families);

+  // Utility function to do some debug validation and sort the given vector
+  // of MultiGet keys
+  void PrepareMultiGetKeys(
+      const size_t num_keys, bool sorted,
+      autovector<KeyContext*, MultiGetContext::MAX_BATCH_SIZE>* key_ptrs);
+
+  // A structure to hold the information required to process MultiGet of keys
+  // belonging to one column family. For a multi column family MultiGet, there
+  // will be a container of these objects.
+  struct MultiGetColumnFamilyData {
+    ColumnFamilyHandle* cf;
+    ColumnFamilyData* cfd;
+
+    // For the batched MultiGet which relies on sorted keys, start specifies
+    // the index of first key belonging to this column family in the sorted
+    // list.
+    size_t start;
+
+    // For the batched MultiGet case, num_keys specifies the number of keys
+    // belonging to this column family in the sorted list
+    size_t num_keys;
+
+    // SuperVersion for the column family obtained in a manner that ensures a
+    // consistent view across all column families in the DB
+    SuperVersion* super_version;
+    MultiGetColumnFamilyData(ColumnFamilyHandle* column_family,
+                             SuperVersion* sv)
+        : cf(column_family),
+          cfd(static_cast<ColumnFamilyHandleImpl*>(cf)->cfd()),
+          start(0),
+          num_keys(0),
+          super_version(sv) {}
+
+    MultiGetColumnFamilyData(ColumnFamilyHandle* column_family, size_t first,
+                             size_t count, SuperVersion* sv)
+        : cf(column_family),
+          cfd(static_cast<ColumnFamilyHandleImpl*>(cf)->cfd()),
+          start(first),
+          num_keys(count),
+          super_version(sv) {}
+
+    MultiGetColumnFamilyData() = default;
+  };
+
+  // A common function to obtain a consistent snapshot, which can be implicit
+  // if the user doesn't specify a snapshot in read_options, across
+  // multiple column families for MultiGet. It will attempt to get an implicit
+  // snapshot without acquiring the db_mutes, but will give up after a few
+  // tries and acquire the mutex if a memtable flush happens. The template
+  // allows both the batched and non-batched MultiGet to call this with
+  // either an std::unordered_map or autovector of column families.
+  //
+  // If callback is non-null, the callback is refreshed with the snapshot
+  // sequence number
+  //
+  // A return value of true indicates that the SuperVersions were obtained
+  // from the ColumnFamilyData, whereas false indicates they are thread
+  // local
+  template <class T>
+  bool MultiCFSnapshot(
+      const ReadOptions& read_options, ReadCallback* callback,
+      std::function<MultiGetColumnFamilyData*(typename T::iterator&)>&
+          iter_deref_func,
+      T* cf_list, SequenceNumber* snapshot);
+
+  // The actual implementation of the batching MultiGet. The caller is expected
+  // to have acquired the SuperVersion and pass in a snapshot sequence number
+  // in order to construct the LookupKeys. The start_key and num_keys specify
+  // the range of keys in the sorted_keys vector for a single column family.
+  void MultiGetImpl(
+      const ReadOptions& read_options, size_t start_key, size_t num_keys,
+      autovector<KeyContext*, MultiGetContext::MAX_BATCH_SIZE>* sorted_keys,
+      SuperVersion* sv, SequenceNumber snap_seqnum, ReadCallback* callback,
+      bool* is_blob_index);
+
  // table_cache_ provides its own synchronization
  std::shared_ptr<Cache> table_cache_;

@@ -1589,6 +1745,7 @@ class DBImpl : public DB {
  InstrumentedMutex log_write_mutex_;

  std::atomic<bool> shutting_down_;
+  std::atomic<bool> manual_compaction_paused_;
  // This condition variable is signaled on these conditions:
  // * whenever bg_compaction_scheduled_ goes down to 0
  // * if AnyManualCompaction, whenever a compaction finishes, even if it hasn't
@@ -1681,8 +1838,6 @@ class DBImpl : public DB {

  WriteController write_controller_;

-  std::unique_ptr<RateLimiter> low_pri_write_rate_limiter_;
-
  // Size of the last batch group. In slowdown mode, next write needs to
  // sleep if it uses up the quota.
  // Note: This is to protect memtable and compaction. If the batch only writes
@@ -1691,6 +1846,8 @@ class DBImpl : public DB {

  FlushScheduler flush_scheduler_;

+  TrimHistoryScheduler trim_history_scheduler_;
+
  SnapshotList snapshots_;

  // For each background job, pending_outputs_ keeps the current file number at
@@ -1729,15 +1886,16 @@ class DBImpl : public DB {
  // ColumnFamilyData::pending_compaction_ == true)
  std::deque<ColumnFamilyData*> compaction_queue_;

-  // A queue to store filenames of the files to be purged
-  std::deque<PurgeFileInfo> purge_queue_;
+  // A map to store file numbers and filenames of the files to be purged
+  std::unordered_map<uint64_t, PurgeFileInfo> purge_files_;

  // A vector to store the file numbers that have been assigned to certain
  // JobContext. Current implementation tracks ssts only.
-  std::vector<uint64_t> files_grabbed_for_purge_;
+  std::unordered_set<uint64_t> files_grabbed_for_purge_;

  // A queue to store log writers to close
  std::deque<log::Writer*> logs_to_free_queue_;
+  std::deque<SuperVersion*> superversions_to_free_queue_;
  int unscheduled_flushes_;
  int unscheduled_compactions_;

@@ -19,6 +19,7 @@
 #include "monitoring/thread_status_updater.h"
 #include "monitoring/thread_status_util.h"
 #include "test_util/sync_point.h"
+#include "util/cast_util.h"
 #include "util/concurrent_task_limiter_impl.h"

 namespace rocksdb {
@@ -147,7 +148,7 @@ Status DBImpl::FlushMemTableToOutputFile(

  FlushJob flush_job(
      dbname_, cfd, immutable_db_options_, mutable_cf_options,
-      nullptr /* memtable_id */, env_options_for_compaction_, versions_.get(),
+      nullptr /* memtable_id */, file_options_for_compaction_, versions_.get(),
      &mutex_, &shutting_down_, snapshot_seqs, earliest_write_conflict_snapshot,
      snapshot_checker, job_context, log_buffer, directories_.GetDbDir(),
      GetDataDir(cfd, 0U),
@@ -163,8 +164,7 @@ Status DBImpl::FlushMemTableToOutputFile(

 #ifndef ROCKSDB_LITE
  // may temporarily unlock and lock the mutex.
-  NotifyOnFlushBegin(cfd, &file_meta, mutable_cf_options, job_context->job_id,
-                     flush_job.GetTableProperties());
+  NotifyOnFlushBegin(cfd, &file_meta, mutable_cf_options, job_context->job_id);
 #endif  // ROCKSDB_LITE

  Status s;
@@ -212,8 +212,8 @@ Status DBImpl::FlushMemTableToOutputFile(
  if (s.ok()) {
 #ifndef ROCKSDB_LITE
    // may temporarily unlock and lock the mutex.
-    NotifyOnFlushCompleted(cfd, &file_meta, mutable_cf_options,
-                           job_context->job_id, flush_job.GetTableProperties());
+    NotifyOnFlushCompleted(cfd, mutable_cf_options,
+                           flush_job.GetCommittedFlushJobsInfo());
    auto sfm = static_cast<SstFileManagerImpl*>(
        immutable_db_options_.sst_file_manager.get());
    if (sfm) {
@@ -232,6 +232,7 @@ Status DBImpl::FlushMemTableToOutputFile(
    }
 #endif  // ROCKSDB_LITE
  }
+  TEST_SYNC_POINT("DBImpl::FlushMemTableToOutputFile:Finish");
  return s;
 }

@@ -302,7 +303,7 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(

  autovector<Directory*> distinct_output_dirs;
  autovector<std::string> distinct_output_dir_paths;
-  std::vector<FlushJob> jobs;
+  std::vector<std::unique_ptr<FlushJob>> jobs;
  std::vector<MutableCFOptions> all_mutable_cf_options;
  int num_cfs = static_cast<int>(cfds.size());
  all_mutable_cf_options.reserve(num_cfs);
@@ -329,16 +330,16 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
    all_mutable_cf_options.emplace_back(*cfd->GetLatestMutableCFOptions());
    const MutableCFOptions& mutable_cf_options = all_mutable_cf_options.back();
    const uint64_t* max_memtable_id = &(bg_flush_args[i].max_memtable_id_);
-    jobs.emplace_back(
+    jobs.emplace_back(new FlushJob(
        dbname_, cfd, immutable_db_options_, mutable_cf_options,
-        max_memtable_id, env_options_for_compaction_, versions_.get(), &mutex_,
+        max_memtable_id, file_options_for_compaction_, versions_.get(), &mutex_,
        &shutting_down_, snapshot_seqs, earliest_write_conflict_snapshot,
        snapshot_checker, job_context, log_buffer, directories_.GetDbDir(),
        data_dir, GetCompressionFlush(*cfd->ioptions(), mutable_cf_options),
        stats_, &event_logger_, mutable_cf_options.report_bg_io_stats,
        false /* sync_output_directory */, false /* write_manifest */,
-        thread_pri);
-    jobs.back().PickMemTable();
+        thread_pri));
+    jobs.back()->PickMemTable();
  }

  std::vector<FileMetaData> file_meta(num_cfs);
@@ -350,7 +351,7 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
    const MutableCFOptions& mutable_cf_options = all_mutable_cf_options.at(i);
    // may temporarily unlock and lock the mutex.
    NotifyOnFlushBegin(cfds[i], &file_meta[i], mutable_cf_options,
-                       job_context->job_id, jobs[i].GetTableProperties());
+                       job_context->job_id);
  }
 #endif /* !ROCKSDB_LITE */

@@ -372,7 +373,7 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
    // TODO (yanqin): parallelize jobs with threads.
    for (int i = 1; i != num_cfs; ++i) {
      exec_status[i].second =
-          jobs[i].Run(&logs_with_prep_tracker_, &file_meta[i]);
+          jobs[i]->Run(&logs_with_prep_tracker_, &file_meta[i]);
      exec_status[i].first = true;
    }
    if (num_cfs > 1) {
@@ -381,8 +382,10 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
      TEST_SYNC_POINT(
          "DBImpl::AtomicFlushMemTablesToOutputFiles:SomeFlushJobsComplete:2");
    }
+    assert(exec_status.size() > 0);
+    assert(!file_meta.empty());
    exec_status[0].second =
-        jobs[0].Run(&logs_with_prep_tracker_, &file_meta[0]);
+        jobs[0]->Run(&logs_with_prep_tracker_, &file_meta[0]);
    exec_status[0].first = true;

    Status error_status;
@@ -423,7 +426,7 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
    auto wait_to_install_func = [&]() {
      bool ready = true;
      for (size_t i = 0; i != cfds.size(); ++i) {
-        const auto& mems = jobs[i].GetMemTables();
+        const auto& mems = jobs[i]->GetMemTables();
        if (cfds[i]->IsDropped()) {
          // If the column family is dropped, then do not wait.
          continue;
@@ -464,7 +467,7 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
    autovector<const MutableCFOptions*> mutable_cf_options_list;
    autovector<FileMetaData*> tmp_file_meta;
    for (int i = 0; i != num_cfs; ++i) {
-      const auto& mems = jobs[i].GetMemTables();
+      const auto& mems = jobs[i]->GetMemTables();
      if (!cfds[i]->IsDropped() && !mems.empty()) {
        tmp_cfds.emplace_back(cfds[i]);
        mems_list.emplace_back(&mems);
@@ -500,12 +503,13 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
 #ifndef ROCKSDB_LITE
    auto sfm = static_cast<SstFileManagerImpl*>(
        immutable_db_options_.sst_file_manager.get());
+    assert(all_mutable_cf_options.size() == static_cast<size_t>(num_cfs));
    for (int i = 0; i != num_cfs; ++i) {
      if (cfds[i]->IsDropped()) {
        continue;
      }
-      NotifyOnFlushCompleted(cfds[i], &file_meta[i], all_mutable_cf_options[i],
-                             job_context->job_id, jobs[i].GetTableProperties());
+      NotifyOnFlushCompleted(cfds[i], all_mutable_cf_options[i],
+                             jobs[i]->GetCommittedFlushJobsInfo());
      if (sfm) {
        std::string file_path = MakeTableFileName(
            cfds[i]->ioptions()->cf_paths[0].path, file_meta[i].fd.GetNumber());
@@ -529,12 +533,12 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
    // unref the versions.
    for (int i = 0; i != num_cfs; ++i) {
      if (!exec_status[i].first) {
-        jobs[i].Cancel();
+        jobs[i]->Cancel();
      }
    }
    for (int i = 0; i != num_cfs; ++i) {
      if (exec_status[i].first && exec_status[i].second.ok()) {
-        auto& mems = jobs[i].GetMemTables();
+        auto& mems = jobs[i]->GetMemTables();
        cfds[i]->imm()->RollbackMemtableFlush(mems,
                                              file_meta[i].fd.GetNumber());
      }
@@ -548,7 +552,7 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(

 void DBImpl::NotifyOnFlushBegin(ColumnFamilyData* cfd, FileMetaData* file_meta,
                                const MutableCFOptions& mutable_cf_options,
-                                int job_id, TableProperties prop) {
+                                int job_id) {
 #ifndef ROCKSDB_LITE
  if (immutable_db_options_.listeners.size() == 0U) {
    return;
@@ -566,20 +570,21 @@ void DBImpl::NotifyOnFlushBegin(ColumnFamilyData* cfd, FileMetaData* file_meta,
  // release lock while notifying events
  mutex_.Unlock();
  {
-    FlushJobInfo info;
+    FlushJobInfo info{};
    info.cf_id = cfd->GetID();
    info.cf_name = cfd->GetName();
    // TODO(yhchiang): make db_paths dynamic in case flush does not
    //                 go to L0 in the future.
-    info.file_path = MakeTableFileName(cfd->ioptions()->cf_paths[0].path,
-                                       file_meta->fd.GetNumber());
+    const uint64_t file_number = file_meta->fd.GetNumber();
+    info.file_path =
+        MakeTableFileName(cfd->ioptions()->cf_paths[0].path, file_number);
+    info.file_number = file_number;
    info.thread_id = env_->GetThreadID();
    info.job_id = job_id;
    info.triggered_writes_slowdown = triggered_writes_slowdown;
    info.triggered_writes_stop = triggered_writes_stop;
    info.smallest_seqno = file_meta->fd.smallest_seqno;
    info.largest_seqno = file_meta->fd.largest_seqno;
-    info.table_properties = prop;
    info.flush_reason = cfd->GetFlushReason();
    for (auto listener : immutable_db_options_.listeners) {
      listener->OnFlushBegin(this, info);
@@ -593,15 +598,14 @@ void DBImpl::NotifyOnFlushBegin(ColumnFamilyData* cfd, FileMetaData* file_meta,
  (void)file_meta;
  (void)mutable_cf_options;
  (void)job_id;
-  (void)prop;
 #endif  // ROCKSDB_LITE
 }

-void DBImpl::NotifyOnFlushCompleted(ColumnFamilyData* cfd,
-                                    FileMetaData* file_meta,
-                                    const MutableCFOptions& mutable_cf_options,
-                                    int job_id, TableProperties prop) {
+void DBImpl::NotifyOnFlushCompleted(
+    ColumnFamilyData* cfd, const MutableCFOptions& mutable_cf_options,
+    std::list<std::unique_ptr<FlushJobInfo>>* flush_jobs_info) {
 #ifndef ROCKSDB_LITE
+  assert(flush_jobs_info != nullptr);
  if (immutable_db_options_.listeners.size() == 0U) {
    return;
  }
@@ -618,34 +622,22 @@ void DBImpl::NotifyOnFlushCompleted(ColumnFamilyData* cfd,
  // release lock while notifying events
  mutex_.Unlock();
  {
-    FlushJobInfo info;
-    info.cf_id = cfd->GetID();
-    info.cf_name = cfd->GetName();
-    // TODO(yhchiang): make db_paths dynamic in case flush does not
-    //                 go to L0 in the future.
-    info.file_path = MakeTableFileName(cfd->ioptions()->cf_paths[0].path,
-                                       file_meta->fd.GetNumber());
-    info.thread_id = env_->GetThreadID();
-    info.job_id = job_id;
-    info.triggered_writes_slowdown = triggered_writes_slowdown;
-    info.triggered_writes_stop = triggered_writes_stop;
-    info.smallest_seqno = file_meta->fd.smallest_seqno;
-    info.largest_seqno = file_meta->fd.largest_seqno;
-    info.table_properties = prop;
-    info.flush_reason = cfd->GetFlushReason();
-    for (auto listener : immutable_db_options_.listeners) {
-      listener->OnFlushCompleted(this, info);
+    for (auto& info : *flush_jobs_info) {
+      info->triggered_writes_slowdown = triggered_writes_slowdown;
+      info->triggered_writes_stop = triggered_writes_stop;
+      for (auto listener : immutable_db_options_.listeners) {
+        listener->OnFlushCompleted(this, *info);
+      }
    }
+    flush_jobs_info->clear();
  }
  mutex_.Lock();
  // no need to signal bg_cv_ as it will be signaled at the end of the
  // flush process.
 #else
  (void)cfd;
-  (void)file_meta;
  (void)mutable_cf_options;
-  (void)job_id;
-  (void)prop;
+  (void)flush_jobs_info;
 #endif  // ROCKSDB_LITE
 }

@@ -667,7 +659,7 @@ Status DBImpl::CompactRange(const CompactRangeOptions& options,
    // one/both sides of the interval are unbounded. But it requires more
    // changes to RangesOverlapWithMemtables.
    Range range(*begin, *end);
-    SuperVersion* super_version = cfd->GetReferencedSuperVersion(&mutex_);
+    SuperVersion* super_version = cfd->GetReferencedSuperVersion(this);
    cfd->RangesOverlapWithMemtables({range}, super_version, &flush_needed);
    CleanupSuperVersion(super_version);
  }
@@ -799,31 +791,6 @@ Status DBImpl::CompactRange(const CompactRangeOptions& options,
  return s;
 }

-namespace {
-class SnapshotListFetchCallbackImpl : public SnapshotListFetchCallback {
- public:
-  SnapshotListFetchCallbackImpl(DBImpl* db_impl, Env* env,
-                                uint64_t snap_refresh_nanos, Logger* info_log)
-      : SnapshotListFetchCallback(env, snap_refresh_nanos),
-        db_impl_(db_impl),
-        info_log_(info_log) {}
-  virtual void Refresh(std::vector<SequenceNumber>* snapshots,
-                       SequenceNumber max) override {
-    size_t prev = snapshots->size();
-    snapshots->clear();
-    db_impl_->LoadSnapshots(snapshots, nullptr, max);
-    size_t now = snapshots->size();
-    ROCKS_LOG_DEBUG(info_log_,
-                    "Compaction snapshot count refreshed from %zu to %zu", prev,
-                    now);
-  }
-
- private:
-  DBImpl* db_impl_;
-  Logger* info_log_;
-};
-}  // namespace
-
 Status DBImpl::CompactFiles(const CompactionOptions& compact_options,
                            ColumnFamilyHandle* column_family,
                            const std::vector<std::string>& input_file_names,
@@ -916,6 +883,9 @@ Status DBImpl::CompactFilesImpl(
  if (shutting_down_.load(std::memory_order_acquire)) {
    return Status::ShutdownInProgress();
  }
+  if (manual_compaction_paused_.load(std::memory_order_acquire)) {
+    return Status::Incomplete(Status::SubCode::kManualCompactionPaused);
+  }

  std::unordered_set<uint64_t> input_set;
  for (const auto& file_name : input_file_names) {
@@ -990,26 +960,22 @@ Status DBImpl::CompactFilesImpl(
  GetSnapshotContext(job_context, &snapshot_seqs,
                     &earliest_write_conflict_snapshot, &snapshot_checker);

-  auto pending_outputs_inserted_elem =
-      CaptureCurrentFileNumberInPendingOutputs();
+  std::unique_ptr<std::list<uint64_t>::iterator> pending_outputs_inserted_elem(
+      new std::list<uint64_t>::iterator(
+          CaptureCurrentFileNumberInPendingOutputs()));

  assert(is_snapshot_supported_ || snapshots_.empty());
  CompactionJobStats compaction_job_stats;
-  SnapshotListFetchCallbackImpl fetch_callback(
-      this, env_, c->mutable_cf_options()->snap_refresh_nanos,
-      immutable_db_options_.info_log.get());
  CompactionJob compaction_job(
      job_context->job_id, c.get(), immutable_db_options_,
-      env_options_for_compaction_, versions_.get(), &shutting_down_,
+      file_options_for_compaction_, versions_.get(), &shutting_down_,
      preserve_deletes_seqnum_.load(), log_buffer, directories_.GetDbDir(),
      GetDataDir(c->column_family_data(), c->output_path_id()), stats_, &mutex_,
      &error_handler_, snapshot_seqs, earliest_write_conflict_snapshot,
      snapshot_checker, table_cache_, &event_logger_,
      c->mutable_cf_options()->paranoid_file_checks,
      c->mutable_cf_options()->report_bg_io_stats, dbname_,
-      &compaction_job_stats, Env::Priority::USER,
-      immutable_db_options_.max_subcompactions <= 1 ? &fetch_callback
-                                                    : nullptr);
+      &compaction_job_stats, Env::Priority::USER, &manual_compaction_paused_);

  // Creating a compaction influences the compaction score because the score
  // takes running compactions into account (by skipping files that are already
@@ -1055,6 +1021,12 @@ Status DBImpl::CompactFilesImpl(
    // Done
  } else if (status.IsColumnFamilyDropped() || status.IsShutdownInProgress()) {
    // Ignore compaction errors found during shutting down
+  } else if (status.IsManualCompactionPaused()) {
+    // Don't report stopping manual compaction as error
+    ROCKS_LOG_INFO(immutable_db_options_.info_log,
+                   "[%s] [JOB %d] Stopping manual compaction",
+                   c->column_family_data()->GetName().c_str(),
+                   job_context->job_id);
  } else {
    ROCKS_LOG_WARN(immutable_db_options_.info_log,
                   "[%s] [JOB %d] Compaction error: %s",
@@ -1125,13 +1097,17 @@ void DBImpl::NotifyOnCompactionBegin(ColumnFamilyData* cfd, Compaction* c,
  if (shutting_down_.load(std::memory_order_acquire)) {
    return;
  }
+  if (c->is_manual_compaction() &&
+      manual_compaction_paused_.load(std::memory_order_acquire)) {
+    return;
+  }
  Version* current = cfd->current();
  current->Ref();
  // release lock while notifying events
  mutex_.Unlock();
  TEST_SYNC_POINT("DBImpl::NotifyOnCompactionBegin::UnlockMutex");
  {
-    CompactionJobInfo info;
+    CompactionJobInfo info{};
    info.cf_name = cfd->GetName();
    info.status = st;
    info.thread_id = env_->GetThreadID();
@@ -1144,9 +1120,13 @@ void DBImpl::NotifyOnCompactionBegin(ColumnFamilyData* cfd, Compaction* c,
    info.compression = c->output_compression();
    for (size_t i = 0; i < c->num_input_levels(); ++i) {
      for (const auto fmd : *c->inputs(i)) {
+        const FileDescriptor& desc = fmd->fd;
+        const uint64_t file_number = desc.GetNumber();
        auto fn = TableFileName(c->immutable_cf_options()->cf_paths,
-                                fmd->fd.GetNumber(), fmd->fd.GetPathId());
+                                file_number, desc.GetPathId());
        info.input_files.push_back(fn);
+        info.input_file_infos.push_back(CompactionFileInfo{
+            static_cast<int>(i), file_number, fmd->oldest_blob_file_number});
        if (info.table_properties.count(fn) == 0) {
          std::shared_ptr<const TableProperties> tp;
          auto s = current->GetTableProperties(&tp, fmd, &fn);
@@ -1157,9 +1137,13 @@ void DBImpl::NotifyOnCompactionBegin(ColumnFamilyData* cfd, Compaction* c,
      }
    }
    for (const auto newf : c->edit()->GetNewFiles()) {
+      const FileMetaData& meta = newf.second;
+      const FileDescriptor& desc = meta.fd;
+      const uint64_t file_number = desc.GetNumber();
      info.output_files.push_back(TableFileName(
-          c->immutable_cf_options()->cf_paths, newf.second.fd.GetNumber(),
-          newf.second.fd.GetPathId()));
+          c->immutable_cf_options()->cf_paths, file_number, desc.GetPathId()));
+      info.output_file_infos.push_back(CompactionFileInfo{
+          newf.first, file_number, meta.oldest_blob_file_number});
    }
    for (auto listener : immutable_db_options_.listeners) {
      listener->OnCompactionBegin(this, info);
@@ -1187,13 +1171,17 @@ void DBImpl::NotifyOnCompactionCompleted(
  if (shutting_down_.load(std::memory_order_acquire)) {
    return;
  }
+  if (c->is_manual_compaction() &&
+      manual_compaction_paused_.load(std::memory_order_acquire)) {
+    return;
+  }
  Version* current = cfd->current();
  current->Ref();
  // release lock while notifying events
  mutex_.Unlock();
  TEST_SYNC_POINT("DBImpl::NotifyOnCompactionCompleted::UnlockMutex");
  {
-    CompactionJobInfo info;
+    CompactionJobInfo info{};
    BuildCompactionJobInfo(cfd, c, st, compaction_job_stats, job_id, current,
                           &info);
    for (auto listener : immutable_db_options_.listeners) {
@@ -1268,7 +1256,8 @@ Status DBImpl::ReFitLevel(ColumnFamilyData* cfd, int level, int target_level) {
      edit.AddFile(to_level, f->fd.GetNumber(), f->fd.GetPathId(),
                   f->fd.GetFileSize(), f->smallest, f->largest,
                   f->fd.smallest_seqno, f->fd.largest_seqno,
-                   f->marked_for_compaction);
+                   f->marked_for_compaction, f->oldest_blob_file_number,
+                   f->oldest_ancester_time, f->file_creation_time);
    }
    ROCKS_LOG_DEBUG(immutable_db_options_.info_log,
                    "[%s] Apply version edit:\n%s", cfd->GetName().c_str(),
@@ -1544,9 +1533,14 @@ Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,
    InstrumentedMutexLock guard_lock(&mutex_);

    WriteThread::Writer w;
+    WriteThread::Writer nonmem_w;
    if (!writes_stopped) {
      write_thread_.EnterUnbatched(&w, &mutex_);
+      if (two_write_queues_) {
+        nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
+      }
    }
+    WaitForPendingWrites();

    if (!cfd->mem()->IsEmpty() || !cached_recoverable_state_empty_.load()) {
      s = SwitchMemtable(cfd, &context);
@@ -1577,7 +1571,8 @@ Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,
          if (stats_cf_flush_needed) {
            ROCKS_LOG_INFO(immutable_db_options_.info_log,
                           "Force flushing stats CF with manual flush of %s "
-                           "to avoid holding old logs", cfd->GetName().c_str());
+                           "to avoid holding old logs",
+                           cfd->GetName().c_str());
            s = SwitchMemtable(cfd_stats, &context);
            flush_memtable_id = cfd_stats->imm()->GetLatestMemTableID();
            flush_req.emplace_back(cfd_stats, flush_memtable_id);
@@ -1607,6 +1602,9 @@ Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,

    if (!writes_stopped) {
      write_thread_.ExitUnbatched(&w);
+      if (two_write_queues_) {
+        nonmem_write_thread_.ExitUnbatched(&nonmem_w);
+      }
    }
  }
  TEST_SYNC_POINT("DBImpl::FlushMemTable:AfterScheduleFlush");
@@ -1620,19 +1618,16 @@ Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,
    }
    s = WaitForFlushMemTables(cfds, flush_memtable_ids,
                              (flush_reason == FlushReason::kErrorRecovery));
+    InstrumentedMutexLock lock_guard(&mutex_);
    for (auto* tmp_cfd : cfds) {
-      if (tmp_cfd->Unref()) {
-        // Only one thread can reach here.
-        InstrumentedMutexLock lock_guard(&mutex_);
-        delete tmp_cfd;
-      }
+      tmp_cfd->UnrefAndTryDelete();
    }
  }
-  TEST_SYNC_POINT("FlushMemTableFinished");
+  TEST_SYNC_POINT("DBImpl::FlushMemTable:FlushMemTableFinished");
  return s;
 }

-// Flush all elments in 'column_family_datas'
+// Flush all elements in 'column_family_datas'
 // and atomically record the result to the MANIFEST.
 Status DBImpl::AtomicFlushMemTables(
    const autovector<ColumnFamilyData*>& column_family_datas,
@@ -1661,9 +1656,14 @@ Status DBImpl::AtomicFlushMemTables(
    InstrumentedMutexLock guard_lock(&mutex_);

    WriteThread::Writer w;
+    WriteThread::Writer nonmem_w;
    if (!writes_stopped) {
      write_thread_.EnterUnbatched(&w, &mutex_);
+      if (two_write_queues_) {
+        nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
+      }
    }
+    WaitForPendingWrites();

    for (auto cfd : column_family_datas) {
      if (cfd->IsDropped()) {
@@ -1680,7 +1680,7 @@ Status DBImpl::AtomicFlushMemTables(
      }
      cfd->Ref();
      s = SwitchMemtable(cfd, &context);
-      cfd->Unref();
+      cfd->UnrefAndTryDelete();
      if (!s.ok()) {
        break;
      }
@@ -1706,6 +1706,9 @@ Status DBImpl::AtomicFlushMemTables(

    if (!writes_stopped) {
      write_thread_.ExitUnbatched(&w);
+      if (two_write_queues_) {
+        nonmem_write_thread_.ExitUnbatched(&nonmem_w);
+      }
    }
  }
  TEST_SYNC_POINT("DBImpl::AtomicFlushMemTables:AfterScheduleFlush");
@@ -1717,12 +1720,9 @@ Status DBImpl::AtomicFlushMemTables(
    }
    s = WaitForFlushMemTables(cfds, flush_memtable_ids,
                              (flush_reason == FlushReason::kErrorRecovery));
+    InstrumentedMutexLock lock_guard(&mutex_);
    for (auto* cfd : cfds) {
-      if (cfd->Unref()) {
-        // Only one thread can reach here.
-        InstrumentedMutexLock lock_guard(&mutex_);
-        delete cfd;
-      }
+      cfd->UnrefAndTryDelete();
    }
  }
  return s;
@@ -1876,6 +1876,14 @@ Status DBImpl::EnableAutoCompaction(
  return s;
 }

+void DBImpl::DisableManualCompaction() {
+  manual_compaction_paused_.store(true, std::memory_order_release);
+}
+
+void DBImpl::EnableManualCompaction() {
+  manual_compaction_paused_.store(false, std::memory_order_release);
+}
+
 void DBImpl::MaybeScheduleFlushOrCompaction() {
  mutex_.AssertHeld();
  if (!opened_successfully_) {
@@ -1906,6 +1914,10 @@ void DBImpl::MaybeScheduleFlushOrCompaction() {
    fta->thread_pri_ = Env::Priority::HIGH;
    env_->Schedule(&DBImpl::BGWorkFlush, fta, Env::Priority::HIGH, this,
                   &DBImpl::UnscheduleFlushCallback);
+    --unscheduled_flushes_;
+    TEST_SYNC_POINT_CALLBACK(
+        "DBImpl::MaybeScheduleFlushOrCompaction:AfterSchedule:0",
+        &unscheduled_flushes_);
  }

  // special case -- if high-pri (flush) thread pool is empty, then schedule
@@ -1920,6 +1932,7 @@ void DBImpl::MaybeScheduleFlushOrCompaction() {
      fta->thread_pri_ = Env::Priority::LOW;
      env_->Schedule(&DBImpl::BGWorkFlush, fta, Env::Priority::LOW, this,
                     &DBImpl::UnscheduleFlushCallback);
+      --unscheduled_flushes_;
    }
  }

@@ -2003,8 +2016,6 @@ ColumnFamilyData* DBImpl::PopFirstFromCompactionQueue() {
 DBImpl::FlushRequest DBImpl::PopFirstFromFlushQueue() {
  assert(!flush_queue_.empty());
  FlushRequest flush_req = flush_queue_.front();
-  assert(unscheduled_flushes_ >= static_cast<int>(flush_req.size()));
-  unscheduled_flushes_ -= static_cast<int>(flush_req.size());
  flush_queue_.pop_front();
  // TODO: need to unset flush reason?
  return flush_req;
@@ -2046,7 +2057,7 @@ void DBImpl::SchedulePendingFlush(const FlushRequest& flush_req,
    cfd->Ref();
    cfd->SetFlushReason(flush_reason);
  }
-  unscheduled_flushes_ += static_cast<int>(flush_req.size());
+  ++unscheduled_flushes_;
  flush_queue_.push_back(flush_req);
 }

@@ -2061,7 +2072,7 @@ void DBImpl::SchedulePendingPurge(std::string fname, std::string dir_to_sync,
                                  FileType type, uint64_t number, int job_id) {
  mutex_.AssertHeld();
  PurgeFileInfo file_info(fname, dir_to_sync, type, number, job_id);
-  purge_queue_.push_back(std::move(file_info));
+  purge_files_.insert({{number, std::move(file_info)}});
 }

 void DBImpl::BGWorkFlush(void* arg) {
@@ -2070,7 +2081,8 @@ void DBImpl::BGWorkFlush(void* arg) {

  IOSTATS_SET_THREAD_POOL_ID(fta.thread_pri_);
  TEST_SYNC_POINT("DBImpl::BGWorkFlush");
-  reinterpret_cast<DBImpl*>(fta.db_)->BackgroundCallFlush(fta.thread_pri_);
+  static_cast_with_check<DBImpl, DB>(fta.db_)->BackgroundCallFlush(
+      fta.thread_pri_);
  TEST_SYNC_POINT("DBImpl::BGWorkFlush:done");
 }

@@ -2081,7 +2093,7 @@ void DBImpl::BGWorkCompaction(void* arg) {
  TEST_SYNC_POINT("DBImpl::BGWorkCompaction");
  auto prepicked_compaction =
      static_cast<PrepickedCompaction*>(ca.prepicked_compaction);
-  reinterpret_cast<DBImpl*>(ca.db)->BackgroundCallCompaction(
+  static_cast_with_check<DBImpl, DB>(ca.db)->BackgroundCallCompaction(
      prepicked_compaction, Env::Priority::LOW);
  delete prepicked_compaction;
 }
@@ -2191,16 +2203,13 @@ Status DBImpl::BackgroundFlush(bool* made_progress, JobContext* job_context,
    *reason = bg_flush_args[0].cfd_->GetFlushReason();
    for (auto& arg : bg_flush_args) {
      ColumnFamilyData* cfd = arg.cfd_;
-      if (cfd->Unref()) {
-        delete cfd;
+      if (cfd->UnrefAndTryDelete()) {
        arg.cfd_ = nullptr;
      }
    }
  }
  for (auto cfd : column_families_not_to_flush) {
-    if (cfd->Unref()) {
-      delete cfd;
-    }
+    cfd->UnrefAndTryDelete();
  }
  return status;
 }
@@ -2218,8 +2227,9 @@ void DBImpl::BackgroundCallFlush(Env::Priority thread_pri) {
    assert(bg_flush_scheduled_);
    num_running_flushes_++;

-    auto pending_outputs_inserted_elem =
-        CaptureCurrentFileNumberInPendingOutputs();
+    std::unique_ptr<std::list<uint64_t>::iterator>
+        pending_outputs_inserted_elem(new std::list<uint64_t>::iterator(
+            CaptureCurrentFileNumberInPendingOutputs()));
    FlushReason reason;

    Status s = BackgroundFlush(&made_progress, &job_context, &log_buffer,
@@ -2300,8 +2310,9 @@ void DBImpl::BackgroundCallCompaction(PrepickedCompaction* prepicked_compaction,

    num_running_compactions_++;

-    auto pending_outputs_inserted_elem =
-        CaptureCurrentFileNumberInPendingOutputs();
+    std::unique_ptr<std::list<uint64_t>::iterator>
+        pending_outputs_inserted_elem(new std::list<uint64_t>::iterator(
+            CaptureCurrentFileNumberInPendingOutputs()));

    assert((bg_thread_pri == Env::Priority::BOTTOM &&
            bg_bottom_compaction_scheduled_) ||
@@ -2315,7 +2326,7 @@ void DBImpl::BackgroundCallCompaction(PrepickedCompaction* prepicked_compaction,
      env_->SleepForMicroseconds(10000);  // prevent hot loop
      mutex_.Lock();
    } else if (!s.ok() && !s.IsShutdownInProgress() &&
-               !s.IsColumnFamilyDropped()) {
+               !s.IsManualCompactionPaused() && !s.IsColumnFamilyDropped()) {
      // Wait a little bit before retrying background compaction in
      // case this is an environmental problem and we do not want to
      // chew up resources for failed compactions for the duration of
@@ -2332,6 +2343,11 @@ void DBImpl::BackgroundCallCompaction(PrepickedCompaction* prepicked_compaction,
      LogFlush(immutable_db_options_.info_log);
      env_->SleepForMicroseconds(1000000);
      mutex_.Lock();
+    } else if (s.IsManualCompactionPaused()) {
+      ManualCompactionState* m = prepicked_compaction->manual_compaction_state;
+      assert(m);
+      ROCKS_LOG_BUFFER(&log_buffer, "[%s] [JOB %d] Manual compaction paused",
+                       m->cfd->GetName().c_str(), job_context.job_id);
    }

    ReleaseFileNumberFromPendingOutputs(pending_outputs_inserted_elem);
@@ -2340,6 +2356,7 @@ void DBImpl::BackgroundCallCompaction(PrepickedCompaction* prepicked_compaction,
    // have created (they might not be all recorded in job_context in case of a
    // failure). Thus, we force full scan in FindObsoleteFiles()
    FindObsoleteFiles(&job_context, !s.ok() && !s.IsShutdownInProgress() &&
+                                        !s.IsManualCompactionPaused() &&
                                        !s.IsColumnFamilyDropped());
    TEST_SYNC_POINT("DBImpl::BackgroundCallCompaction:FoundObsoleteFiles");

@@ -2423,6 +2440,9 @@ Status DBImpl::BackgroundCompaction(bool* made_progress,
  if (!error_handler_.IsBGWorkStopped()) {
    if (shutting_down_.load(std::memory_order_acquire)) {
      status = Status::ShutdownInProgress();
+    } else if (is_manual &&
+               manual_compaction_paused_.load(std::memory_order_acquire)) {
+      status = Status::Incomplete(Status::SubCode::kManualCompactionPaused);
    }
  } else {
    status = error_handler_.GetBGError();
@@ -2518,10 +2538,9 @@ Status DBImpl::BackgroundCompaction(bool* made_progress,
    // reference).
    // This will all happen under a mutex so we don't have to be afraid of
    // somebody else deleting it.
-    if (cfd->Unref()) {
+    if (cfd->UnrefAndTryDelete()) {
      // This was the last reference of the column family, so no need to
      // compact.
-      delete cfd;
      return Status::OK();
    }

@@ -2647,7 +2666,9 @@ Status DBImpl::BackgroundCompaction(bool* made_progress,
        c->edit()->AddFile(c->output_level(), f->fd.GetNumber(),
                           f->fd.GetPathId(), f->fd.GetFileSize(), f->smallest,
                           f->largest, f->fd.smallest_seqno,
-                           f->fd.largest_seqno, f->marked_for_compaction);
+                           f->fd.largest_seqno, f->marked_for_compaction,
+                           f->oldest_blob_file_number, f->oldest_ancester_time,
+                           f->file_creation_time);

        ROCKS_LOG_BUFFER(
            log_buffer,
@@ -2724,12 +2745,9 @@ Status DBImpl::BackgroundCompaction(bool* made_progress,
    GetSnapshotContext(job_context, &snapshot_seqs,
                       &earliest_write_conflict_snapshot, &snapshot_checker);
    assert(is_snapshot_supported_ || snapshots_.empty());
-    SnapshotListFetchCallbackImpl fetch_callback(
-        this, env_, c->mutable_cf_options()->snap_refresh_nanos,
-        immutable_db_options_.info_log.get());
    CompactionJob compaction_job(
        job_context->job_id, c.get(), immutable_db_options_,
-        env_options_for_compaction_, versions_.get(), &shutting_down_,
+        file_options_for_compaction_, versions_.get(), &shutting_down_,
        preserve_deletes_seqnum_.load(), log_buffer, directories_.GetDbDir(),
        GetDataDir(c->column_family_data(), c->output_path_id()), stats_,
        &mutex_, &error_handler_, snapshot_seqs,
@@ -2737,8 +2755,7 @@ Status DBImpl::BackgroundCompaction(bool* made_progress,
        &event_logger_, c->mutable_cf_options()->paranoid_file_checks,
        c->mutable_cf_options()->report_bg_io_stats, dbname_,
        &compaction_job_stats, thread_pri,
-        immutable_db_options_.max_subcompactions <= 1 ? &fetch_callback
-                                                      : nullptr);
+        is_manual ? &manual_compaction_paused_ : nullptr);
    compaction_job.Prepare();

    NotifyOnCompactionBegin(c->column_family_data(), c.get(), status,
@@ -2778,7 +2795,8 @@ Status DBImpl::BackgroundCompaction(bool* made_progress,
                                compaction_job_stats, job_context->job_id);
  }

-  if (status.ok() || status.IsCompactionTooLarge()) {
+  if (status.ok() || status.IsCompactionTooLarge() ||
+      status.IsManualCompactionPaused()) {
    // Done
  } else if (status.IsColumnFamilyDropped() || status.IsShutdownInProgress()) {
    // Ignore compaction errors found during shutting down
@@ -2959,9 +2977,13 @@ void DBImpl::BuildCompactionJobInfo(
  compaction_job_info->compression = c->output_compression();
  for (size_t i = 0; i < c->num_input_levels(); ++i) {
    for (const auto fmd : *c->inputs(i)) {
-      auto fn = TableFileName(c->immutable_cf_options()->cf_paths,
-                              fmd->fd.GetNumber(), fmd->fd.GetPathId());
+      const FileDescriptor& desc = fmd->fd;
+      const uint64_t file_number = desc.GetNumber();
+      auto fn = TableFileName(c->immutable_cf_options()->cf_paths, file_number,
+                              desc.GetPathId());
      compaction_job_info->input_files.push_back(fn);
+      compaction_job_info->input_file_infos.push_back(CompactionFileInfo{
+          static_cast<int>(i), file_number, fmd->oldest_blob_file_number});
      if (compaction_job_info->table_properties.count(fn) == 0) {
        std::shared_ptr<const TableProperties> tp;
        auto s = current->GetTableProperties(&tp, fmd, &fn);
@@ -2972,9 +2994,13 @@ void DBImpl::BuildCompactionJobInfo(
    }
  }
  for (const auto& newf : c->edit()->GetNewFiles()) {
-    compaction_job_info->output_files.push_back(
-        TableFileName(c->immutable_cf_options()->cf_paths,
-                      newf.second.fd.GetNumber(), newf.second.fd.GetPathId()));
+    const FileMetaData& meta = newf.second;
+    const FileDescriptor& desc = meta.fd;
+    const uint64_t file_number = desc.GetNumber();
+    compaction_job_info->output_files.push_back(TableFileName(
+        c->immutable_cf_options()->cf_paths, file_number, desc.GetPathId()));
+    compaction_job_info->output_file_infos.push_back(CompactionFileInfo{
+        newf.first, file_number, meta.oldest_blob_file_number});
  }
 }
 #endif
@@ -3033,34 +3059,20 @@ void DBImpl::InstallSuperVersionAndScheduleWork(
 }

 // ShouldPurge is called by FindObsoleteFiles when doing a full scan,
-// and db mutex (mutex_) should already be held. This function performs a
-// linear scan of an vector (files_grabbed_for_purge_) in search of a
-// certain element. We expect FindObsoleteFiles with full scan to occur once
-// every 10 hours by default, and the size of the vector is small.
-// Therefore, the cost is affordable even if the mutex is held.
+// and db mutex (mutex_) should already be held.
 // Actually, the current implementation of FindObsoleteFiles with
 // full_scan=true can issue I/O requests to obtain list of files in
 // directories, e.g. env_->getChildren while holding db mutex.
-// In the future, if we want to reduce the cost of search, we may try to keep
-// the vector sorted.
 bool DBImpl::ShouldPurge(uint64_t file_number) const {
-  for (auto fn : files_grabbed_for_purge_) {
-    if (file_number == fn) {
-      return false;
-    }
-  }
-  for (const auto& purge_file_info : purge_queue_) {
-    if (purge_file_info.number == file_number) {
-      return false;
-    }
-  }
-  return true;
+  return files_grabbed_for_purge_.find(file_number) ==
+             files_grabbed_for_purge_.end() &&
+         purge_files_.find(file_number) == purge_files_.end();
 }

 // MarkAsGrabbedForPurge is called by FindObsoleteFiles, and db mutex
 // (mutex_) should already be held.
 void DBImpl::MarkAsGrabbedForPurge(uint64_t file_number) {
-  files_grabbed_for_purge_.emplace_back(file_number);
+  files_grabbed_for_purge_.insert(file_number);
 }

 void DBImpl::SetSnapshotChecker(SnapshotChecker* snapshot_checker) {
@@ -9,12 +9,13 @@

 #ifndef NDEBUG

+#include "db/column_family.h"
 #include "db/db_impl/db_impl.h"
 #include "db/error_handler.h"
 #include "monitoring/thread_status_updater.h"
+#include "util/cast_util.h"

 namespace rocksdb {
-
 uint64_t DBImpl::TEST_GetLevel0TotalSize() {
  InstrumentedMutexLock l(&mutex_);
  return default_cf_handle_->cfd()->current()->storage_info()->NumLevelBytes(0);
@@ -104,7 +105,16 @@ Status DBImpl::TEST_SwitchMemtable(ColumnFamilyData* cfd) {
  if (cfd == nullptr) {
    cfd = default_cf_handle_->cfd();
  }
-  return SwitchMemtable(cfd, &write_context);
+
+  if (two_write_queues_) {
+    WriteThread::Writer nonmem_w;
+    nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
+    Status s = SwitchMemtable(cfd, &write_context);
+    nonmem_write_thread_.ExitUnbatched(&nonmem_w);
+    return s;
+  } else {
+    return SwitchMemtable(cfd, &write_context);
+  }
 }

 Status DBImpl::TEST_FlushMemTable(bool wait, bool allow_write_stall,
@@ -128,7 +128,8 @@ Status DBImpl::PromoteL0(ColumnFamilyHandle* column_family, int target_level) {
      edit.AddFile(target_level, f->fd.GetNumber(), f->fd.GetPathId(),
                   f->fd.GetFileSize(), f->smallest, f->largest,
                   f->fd.smallest_seqno, f->fd.largest_seqno,
-                   f->marked_for_compaction);
+                   f->marked_for_compaction, f->oldest_blob_file_number,
+                   f->oldest_ancester_time, f->file_creation_time);
    }

    status = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
@@ -15,6 +15,7 @@
 #include "db/memtable_list.h"
 #include "file/file_util.h"
 #include "file/sst_file_manager_impl.h"
+#include "util/autovector.h"

 namespace rocksdb {

@@ -316,11 +317,9 @@ void DBImpl::PurgeObsoleteFiles(JobContext& state, bool schedule_only) {
      candidate_files.size() + state.sst_delete_files.size() +
      state.log_delete_files.size() + state.manifest_delete_files.size());
  // We may ignore the dbname when generating the file names.
-  const char* kDumbDbName = "";
  for (auto& file : state.sst_delete_files) {
    candidate_files.emplace_back(
-        MakeTableFileName(kDumbDbName, file.metadata->fd.GetNumber()),
-        file.path);
+        MakeTableFileName(file.metadata->fd.GetNumber()), file.path);
    if (file.metadata->table_reader_handle) {
      table_cache_->Release(file.metadata->table_reader_handle);
    }
@@ -329,7 +328,7 @@ void DBImpl::PurgeObsoleteFiles(JobContext& state, bool schedule_only) {

  for (auto file_num : state.log_delete_files) {
    if (file_num > 0) {
-      candidate_files.emplace_back(LogFileName(kDumbDbName, file_num),
+      candidate_files.emplace_back(LogFileName(file_num),
                                   immutable_db_options_.wal_dir);
    }
  }
@@ -380,6 +379,13 @@ void DBImpl::PurgeObsoleteFiles(JobContext& state, bool schedule_only) {
    }
  }

+  // Close WALs before trying to delete them.
+  for (const auto w : state.logs_to_free) {
+    // TODO: maybe check the return value of Close.
+    w->Close();
+  }
+
+  bool own_files = OwnTablesAndLogs();
  std::unordered_set<uint64_t> files_to_del;
  for (const auto& candidate_file : candidate_files) {
    const std::string& to_delete = candidate_file.file_name;
@@ -479,11 +485,12 @@ void DBImpl::PurgeObsoleteFiles(JobContext& state, bool schedule_only) {
    }
 #endif  // !ROCKSDB_LITE

-    for (const auto w : state.logs_to_free) {
-      // TODO: maybe check the return value of Close.
-      w->Close();
+    // If I do not own these files, e.g. secondary instance with max_open_files
+    // = -1, then no need to delete or schedule delete these files since they
+    // will be removed by their owner, e.g. the primary instance.
+    if (!own_files) {
+      continue;
    }
-
    Status file_deletion_status;
    if (schedule_only) {
      InstrumentedMutexLock guard_lock(&mutex_);
@@ -495,15 +502,16 @@ void DBImpl::PurgeObsoleteFiles(JobContext& state, bool schedule_only) {

  {
    // After purging obsolete files, remove them from files_grabbed_for_purge_.
-    // Use a temporary vector to perform bulk deletion via swap.
    InstrumentedMutexLock guard_lock(&mutex_);
-    std::vector<uint64_t> tmp;
+    autovector<uint64_t> to_be_removed;
    for (auto fn : files_grabbed_for_purge_) {
-      if (files_to_del.count(fn) == 0) {
-        tmp.emplace_back(fn);
+      if (files_to_del.count(fn) != 0) {
+        to_be_removed.emplace_back(fn);
      }
    }
-    files_grabbed_for_purge_.swap(tmp);
+    for (auto fn : to_be_removed) {
+      files_grabbed_for_purge_.erase(fn);
+    }
  }

  // Delete old info log files.
@@ -12,7 +12,10 @@

 #include "db/builder.h"
 #include "db/error_handler.h"
+#include "env/composite_env_wrapper.h"
+#include "file/read_write_util.h"
 #include "file/sst_file_manager_impl.h"
+#include "file/writable_file_writer.h"
 #include "monitoring/persistent_stats_history.h"
 #include "options/options_helper.h"
 #include "rocksdb/wal_filter.h"
@@ -32,6 +35,18 @@ Options SanitizeOptions(const std::string& dbname, const Options& src) {
 DBOptions SanitizeOptions(const std::string& dbname, const DBOptions& src) {
  DBOptions result(src);

+  if (result.file_system == nullptr) {
+    if (result.env == Env::Default()) {
+      result.file_system = FileSystem::Default();
+    } else {
+      result.file_system.reset(new LegacyFileSystemWrapper(result.env));
+    }
+  } else {
+    if (result.env == nullptr) {
+      result.env = Env::Default();
+    }
+  }
+
  // result.max_open_files means an "infinite" open files.
  if (result.max_open_files != -1) {
    int max_max_open_files = port::GetMaxOpenFiles();
@@ -133,9 +148,9 @@ DBOptions SanitizeOptions(const std::string& dbname, const DBOptions& src) {
    std::vector<std::string> filenames;
    result.env->GetChildren(result.wal_dir, &filenames);
    for (std::string& filename : filenames) {
-      if (filename.find(".log.trash",
-                  filename.length() - std::string(".log.trash").length()) !=
-                  std::string::npos) {
+      if (filename.find(".log.trash", filename.length() -
+                                          std::string(".log.trash").length()) !=
+          std::string::npos) {
        std::string trash_file = result.wal_dir + "/" + filename;
        result.env->DeleteFile(trash_file);
      }
@@ -226,30 +241,42 @@ Status DBImpl::ValidateOptions(const DBOptions& db_options) {
        "unordered_write is incompatible with enable_pipelined_write");
  }

+  if (db_options.atomic_flush && db_options.enable_pipelined_write) {
+    return Status::InvalidArgument(
+        "atomic_flush is incompatible with enable_pipelined_write");
+  }
+
  return Status::OK();
 }

 Status DBImpl::NewDB() {
  VersionEdit new_db;
+  Status s = SetIdentityFile(env_, dbname_);
+  if (!s.ok()) {
+    return s;
+  }
+  if (immutable_db_options_.write_dbid_to_manifest) {
+    std::string temp_db_id;
+    GetDbIdentityFromIdentityFile(&temp_db_id);
+    new_db.SetDBId(temp_db_id);
+  }
  new_db.SetLogNumber(0);
  new_db.SetNextFile(2);
  new_db.SetLastSequence(0);

-  Status s;
-
  ROCKS_LOG_INFO(immutable_db_options_.info_log, "Creating manifest 1 \n");
  const std::string manifest = DescriptorFileName(dbname_, 1);
  {
-    std::unique_ptr<WritableFile> file;
-    EnvOptions env_options = env_->OptimizeForManifestWrite(env_options_);
-    s = NewWritableFile(env_, manifest, &file, env_options);
+    std::unique_ptr<FSWritableFile> file;
+    FileOptions file_options = fs_->OptimizeForManifestWrite(file_options_);
+    s = NewWritableFile(fs_.get(), manifest, &file, file_options);
    if (!s.ok()) {
      return s;
    }
    file->SetPreallocationBlockSize(
        immutable_db_options_.manifest_preallocation_size);
    std::unique_ptr<WritableFileWriter> file_writer(new WritableFileWriter(
-        std::move(file), manifest, env_options, env_, nullptr /* stats */,
+        std::move(file), manifest, file_options, env_, nullptr /* stats */,
        immutable_db_options_.listeners));
    log::Writer log(std::move(file_writer), 0, false);
    std::string record;
@@ -263,7 +290,7 @@ Status DBImpl::NewDB() {
    // Make "CURRENT" file that points to the new manifest file.
    s = SetCurrentFile(env_, dbname_, 1, directories_.GetDbDir());
  } else {
-    env_->DeleteFile(manifest);
+    fs_->DeleteFile(manifest, IOOptions(), nullptr);
  }
  return s;
 }
@@ -336,9 +363,13 @@ Status DBImpl::Recover(
      return s;
    }

-    s = env_->FileExists(CurrentFileName(dbname_));
+    std::string current_fname = CurrentFileName(dbname_);
+    s = env_->FileExists(current_fname);
    if (s.IsNotFound()) {
      if (immutable_db_options_.create_if_missing) {
+        // Has to be called only after Identity File creation is successful
+        // because DB ID is stored in Manifest if
+        // immutable_db_options_.write_dbid_to_manifest = true
        s = NewDB();
        is_new_db = true;
        if (!s.ok()) {
@@ -346,7 +377,7 @@ Status DBImpl::Recover(
        }
      } else {
        return Status::InvalidArgument(
-            dbname_, "does not exist (create_if_missing is false)");
+            current_fname, "does not exist (create_if_missing is false)");
      }
    } else if (s.ok()) {
      if (immutable_db_options_.error_if_exists) {
@@ -358,31 +389,20 @@ Status DBImpl::Recover(
      assert(s.IsIOError());
      return s;
    }
-    // Check for the IDENTITY file and create it if not there
-    s = env_->FileExists(IdentityFileName(dbname_));
-    if (s.IsNotFound()) {
-      s = SetIdentityFile(env_, dbname_);
-      if (!s.ok()) {
-        return s;
-      }
-    } else if (!s.ok()) {
-      assert(s.IsIOError());
-      return s;
-    }
-    // Verify compatibility of env_options_ and filesystem
+    // Verify compatibility of file_options_ and filesystem
    {
-      std::unique_ptr<RandomAccessFile> idfile;
-      EnvOptions customized_env(env_options_);
-      customized_env.use_direct_reads |=
+      std::unique_ptr<FSRandomAccessFile> idfile;
+      FileOptions customized_fs(file_options_);
+      customized_fs.use_direct_reads |=
          immutable_db_options_.use_direct_io_for_flush_and_compaction;
-      s = env_->NewRandomAccessFile(IdentityFileName(dbname_), &idfile,
-                                    customized_env);
+      s = fs_->NewRandomAccessFile(current_fname, customized_fs, &idfile,
+                                   nullptr);
      if (!s.ok()) {
        std::string error_str = s.ToString();
        // Check if unsupported Direct I/O is the root cause
-        customized_env.use_direct_reads = false;
-        s = env_->NewRandomAccessFile(IdentityFileName(dbname_), &idfile,
-                                      customized_env);
+        customized_fs.use_direct_reads = false;
+        s = fs_->NewRandomAccessFile(current_fname, customized_fs, &idfile,
+                                     nullptr);
        if (s.ok()) {
          return Status::InvalidArgument(
              "Direct I/O is not supported by the specified DB.");
@@ -393,8 +413,42 @@ Status DBImpl::Recover(
      }
    }
  }
-
-  Status s = versions_->Recover(column_families, read_only);
+  assert(db_id_.empty());
+  Status s = versions_->Recover(column_families, read_only, &db_id_);
+  if (!s.ok()) {
+    return s;
+  }
+  // Happens when immutable_db_options_.write_dbid_to_manifest is set to true
+  // the very first time.
+  if (db_id_.empty()) {
+    // Check for the IDENTITY file and create it if not there.
+    s = fs_->FileExists(IdentityFileName(dbname_), IOOptions(), nullptr);
+    // Typically Identity file is created in NewDB() and for some reason if
+    // it is no longer available then at this point DB ID is not in Identity
+    // file or Manifest.
+    if (s.IsNotFound()) {
+      s = SetIdentityFile(env_, dbname_);
+      if (!s.ok()) {
+        return s;
+      }
+    } else if (!s.ok()) {
+      assert(s.IsIOError());
+      return s;
+    }
+    GetDbIdentityFromIdentityFile(&db_id_);
+    if (immutable_db_options_.write_dbid_to_manifest) {
+      VersionEdit edit;
+      edit.SetDBId(db_id_);
+      Options options;
+      MutableCFOptions mutable_cf_options(options);
+      versions_->db_id_ = db_id_;
+      versions_->LogAndApply(versions_->GetColumnFamilySet()->GetDefault(),
+                             mutable_cf_options, &edit, &mutex_, nullptr,
+                             false);
+    }
+  } else {
+    SetIdentityFile(env_, dbname_, db_id_);
+  }

  if (immutable_db_options_.paranoid_checks && s.ok()) {
    s = CheckConsistency();
@@ -708,9 +762,10 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,

    std::unique_ptr<SequentialFileReader> file_reader;
    {
-      std::unique_ptr<SequentialFile> file;
-      status = env_->NewSequentialFile(fname, &file,
-                                       env_->OptimizeForLogRead(env_options_));
+      std::unique_ptr<FSSequentialFile> file;
+      status = fs_->NewSequentialFile(fname,
+                                      fs_->OptimizeForLogRead(file_options_),
+                                      &file, nullptr);
      if (!status.ok()) {
        MaybeIgnoreError(&status);
        if (!status.ok()) {
@@ -862,9 +917,10 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
      // That's why we set ignore missing column families to true
      bool has_valid_writes = false;
      status = WriteBatchInternal::InsertInto(
-          &batch, column_family_memtables_.get(), &flush_scheduler_, true,
-          log_number, this, false /* concurrent_memtable_writes */,
-          next_sequence, &has_valid_writes, seq_per_batch_, batch_per_txn_);
+          &batch, column_family_memtables_.get(), &flush_scheduler_,
+          &trim_history_scheduler_, true, log_number, this,
+          false /* concurrent_memtable_writes */, next_sequence,
+          &has_valid_writes, seq_per_batch_, batch_per_txn_);
      MaybeIgnoreError(&status);
      if (!status.ok()) {
        // We are treating this as a failure while reading since we read valid
@@ -879,7 +935,7 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
        ColumnFamilyData* cfd;

        while ((cfd = flush_scheduler_.TakeNextColumnFamily()) != nullptr) {
-          cfd->Unref();
+          cfd->UnrefAndTryDelete();
          // If this asserts, it means that InsertInto failed in
          // filtering updates to already-flushed column families
          assert(cfd->GetLogNumber() <= log_number);
@@ -931,6 +987,7 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
    }

    flush_scheduler_.Clear();
+    trim_history_scheduler_.Clear();
    auto last_sequence = *next_sequence - 1;
    if ((*next_sequence != kMaxSequenceNumber) &&
        (versions_->LastSequence() <= last_sequence)) {
@@ -981,6 +1038,9 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
        continue;
      }

+      TEST_SYNC_POINT_CALLBACK(
+          "DBImpl::RecoverLogFiles:BeforeFlushFinalMemtable", /*arg=*/nullptr);
+
      // flush the final memtable (if non-empty)
      if (cfd->mem()->GetFirstSequenceNumber() != 0) {
        // If flush happened in the middle of recovery (e.g. due to memtable
@@ -1000,7 +1060,9 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
        data_seen = true;
      }

-      // write MANIFEST with update
+      // Update the log number info in the version edit corresponding to this
+      // column family. Note that the version edits will be written to MANIFEST
+      // together later.
      // writing log_number in the manifest means that any log file
      // with number strongly less than (log_number + 1) is already
      // recovered and should be ignored on next reincarnation.
@@ -1009,17 +1071,28 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
      if (flushed || cfd->mem()->GetFirstSequenceNumber() == 0) {
        edit->SetLogNumber(max_log_number + 1);
      }
+    }
+    if (status.ok()) {
      // we must mark the next log number as used, even though it's
      // not actually used. that is because VersionSet assumes
      // VersionSet::next_file_number_ always to be strictly greater than any
      // log number
      versions_->MarkFileNumberUsed(max_log_number + 1);
-      status = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
-                                      edit, &mutex_);
-      if (!status.ok()) {
-        // Recovery failed
-        break;
+
+      autovector<ColumnFamilyData*> cfds;
+      autovector<const MutableCFOptions*> cf_opts;
+      autovector<autovector<VersionEdit*>> edit_lists;
+      for (auto* cfd : *versions_->GetColumnFamilySet()) {
+        cfds.push_back(cfd);
+        cf_opts.push_back(cfd->GetLatestMutableCFOptions());
+        auto iter = version_edits.find(cfd->GetID());
+        assert(iter != version_edits.end());
+        edit_lists.push_back({&iter->second});
      }
+      // write MANIFEST with update
+      status = versions_->LogAndApply(cfds, cf_opts, edit_lists, &mutex_,
+                                      directories_.GetDbDir(),
+                                      /*new_descriptor_log=*/true);
    }
  }

@@ -1061,17 +1134,18 @@ Status DBImpl::RestoreAliveLogFiles(const std::vector<uint64_t>& log_numbers) {
    // preallocated space are not needed anymore. It is likely only the last
    // log has such preallocated space, so we only truncate for the last log.
    if (log_number == log_numbers.back()) {
-      std::unique_ptr<WritableFile> last_log;
-      Status truncate_status = env_->ReopenWritableFile(
-          fname, &last_log,
-          env_->OptimizeForLogWrite(
-              env_options_,
-              BuildDBOptions(immutable_db_options_, mutable_db_options_)));
+      std::unique_ptr<FSWritableFile> last_log;
+      Status truncate_status = fs_->ReopenWritableFile(
+          fname,
+          fs_->OptimizeForLogWrite(
+              file_options_,
+              BuildDBOptions(immutable_db_options_, mutable_db_options_)),
+          &last_log, nullptr);
      if (truncate_status.ok()) {
-        truncate_status = last_log->Truncate(log.size);
+        truncate_status = last_log->Truncate(log.size, IOOptions(), nullptr);
      }
      if (truncate_status.ok()) {
-        truncate_status = last_log->Close();
+        truncate_status = last_log->Close(IOOptions(), nullptr);
      }
      // Not a critical error if fail to truncate.
      if (!truncate_status.ok()) {
@@ -1092,8 +1166,9 @@ Status DBImpl::WriteLevel0TableForRecovery(int job_id, ColumnFamilyData* cfd,
  mutex_.AssertHeld();
  const uint64_t start_micros = env_->NowMicros();
  FileMetaData meta;
-  auto pending_outputs_inserted_elem =
-      CaptureCurrentFileNumberInPendingOutputs();
+  std::unique_ptr<std::list<uint64_t>::iterator> pending_outputs_inserted_elem(
+      new std::list<uint64_t>::iterator(
+          CaptureCurrentFileNumberInPendingOutputs()));
  meta.fd = FileDescriptor(versions_->NewFileNumber(), 0, 0);
  ReadOptions ro;
  ro.total_order_seek = true;
@@ -1116,6 +1191,7 @@ Status DBImpl::WriteLevel0TableForRecovery(int job_id, ColumnFamilyData* cfd,
    int64_t _current_time = 0;
    env_->GetCurrentTime(&_current_time);  // ignore error
    const uint64_t current_time = static_cast<uint64_t>(_current_time);
+    meta.oldest_ancester_time = current_time;

    {
      auto write_hint = cfd->CalculateSSTWriteHint(0);
@@ -1136,8 +1212,8 @@ Status DBImpl::WriteLevel0TableForRecovery(int job_id, ColumnFamilyData* cfd,
        range_del_iters.emplace_back(range_del_iter);
      }
      s = BuildTable(
-          dbname_, env_, *cfd->ioptions(), mutable_cf_options,
-          env_options_for_compaction_, cfd->table_cache(), iter.get(),
+          dbname_, env_, fs_.get(), *cfd->ioptions(), mutable_cf_options,
+          file_options_for_compaction_, cfd->table_cache(), iter.get(),
          std::move(range_del_iters), &meta, cfd->internal_comparator(),
          cfd->int_tbl_prop_collector_factories(), cfd->GetID(), cfd->GetName(),
          snapshot_seqs, earliest_write_conflict_snapshot, snapshot_checker,
@@ -1165,7 +1241,8 @@ Status DBImpl::WriteLevel0TableForRecovery(int job_id, ColumnFamilyData* cfd,
    edit->AddFile(level, meta.fd.GetNumber(), meta.fd.GetPathId(),
                  meta.fd.GetFileSize(), meta.smallest, meta.largest,
                  meta.fd.smallest_seqno, meta.fd.largest_seqno,
-                  meta.marked_for_compaction);
+                  meta.marked_for_compaction, meta.oldest_blob_file_number,
+                  meta.oldest_ancester_time, meta.file_creation_time);
  }

  InternalStats::CompactionStats stats(CompactionReason::kFlush, 1);
@@ -1219,12 +1296,12 @@ Status DB::Open(const DBOptions& db_options, const std::string& dbname,
 Status DBImpl::CreateWAL(uint64_t log_file_num, uint64_t recycle_log_number,
                         size_t preallocate_block_size, log::Writer** new_log) {
  Status s;
-  std::unique_ptr<WritableFile> lfile;
+  std::unique_ptr<FSWritableFile> lfile;

  DBOptions db_options =
      BuildDBOptions(immutable_db_options_, mutable_db_options_);
-  EnvOptions opt_env_options =
-      env_->OptimizeForLogWrite(env_options_, db_options);
+  FileOptions opt_file_options =
+      fs_->OptimizeForLogWrite(file_options_, db_options);
  std::string log_fname =
      LogFileName(immutable_db_options_.wal_dir, log_file_num);

@@ -1234,10 +1311,10 @@ Status DBImpl::CreateWAL(uint64_t log_file_num, uint64_t recycle_log_number,
                   recycle_log_number);
    std::string old_log_fname =
        LogFileName(immutable_db_options_.wal_dir, recycle_log_number);
-    s = env_->ReuseWritableFile(log_fname, old_log_fname, &lfile,
-                                opt_env_options);
+    s = fs_->ReuseWritableFile(log_fname, old_log_fname, opt_file_options,
+                               &lfile, /*dbg=*/nullptr);
  } else {
-    s = NewWritableFile(env_, log_fname, &lfile, opt_env_options);
+    s = NewWritableFile(fs_.get(), log_fname, &lfile, opt_file_options);
  }

  if (s.ok()) {
@@ -1246,7 +1323,7 @@ Status DBImpl::CreateWAL(uint64_t log_file_num, uint64_t recycle_log_number,

    const auto& listeners = immutable_db_options_.listeners;
    std::unique_ptr<WritableFileWriter> file_writer(
-        new WritableFileWriter(std::move(lfile), log_fname, opt_env_options,
+        new WritableFileWriter(std::move(lfile), log_fname, opt_file_options,
                               env_, nullptr /* stats */, listeners));
    *new_log = new log::Writer(std::move(file_writer), log_file_num,
                               immutable_db_options_.recycle_log_file_num > 0,
@@ -1315,8 +1392,7 @@ Status DBImpl::Open(const DBOptions& db_options, const std::string& dbname,
    return s;
  }

-  impl->wal_in_db_path_ =
-      IsWalDirSameAsDBPath(&impl->immutable_db_options_);
+  impl->wal_in_db_path_ = IsWalDirSameAsDBPath(&impl->immutable_db_options_);

  impl->mutex_.Lock();
  // Handles create_if_missing, error_if_exists
@@ -4,6 +4,7 @@
 //  (found in the LICENSE.Apache file in the root directory).

 #include "db/db_impl/db_impl_readonly.h"
+#include "db/arena_wrapped_db_iter.h"

 #include "db/compacted_db_impl.h"
 #include "db/db_impl/db_impl.h"
@@ -16,6 +16,10 @@ namespace rocksdb {
 class DBImplReadOnly : public DBImpl {
 public:
  DBImplReadOnly(const DBOptions& options, const std::string& dbname);
+  // No copying allowed
+  DBImplReadOnly(const DBImplReadOnly&) = delete;
+  void operator=(const DBImplReadOnly&) = delete;
+
  virtual ~DBImplReadOnly();

  // Implementations of the DB interface
@@ -127,10 +131,6 @@ class DBImplReadOnly : public DBImpl {

 private:
  friend class DB;
-
-  // No copying allowed
-  DBImplReadOnly(const DBImplReadOnly&);
-  void operator=(const DBImplReadOnly&);
 };
 }  // namespace rocksdb

@@ -7,10 +7,11 @@

 #include <cinttypes>

-#include "db/db_iter.h"
+#include "db/arena_wrapped_db_iter.h"
 #include "db/merge_context.h"
 #include "logging/auto_roll_logger.h"
 #include "monitoring/perf_context_imp.h"
+#include "util/cast_util.h"

 namespace rocksdb {

@@ -143,9 +144,10 @@ Status DBImplSecondary::MaybeInitLogReader(

    std::unique_ptr<SequentialFileReader> file_reader;
    {
-      std::unique_ptr<SequentialFile> file;
-      Status status = env_->NewSequentialFile(
-          fname, &file, env_->OptimizeForLogRead(env_options_));
+      std::unique_ptr<FSSequentialFile> file;
+      Status status = fs_->NewSequentialFile(
+          fname, fs_->OptimizeForLogRead(file_options_), &file,
+          nullptr);
      if (!status.ok()) {
        *log_reader = nullptr;
        return status;
@@ -253,9 +255,9 @@ Status DBImplSecondary::RecoverLogFiles(
        bool has_valid_writes = false;
        status = WriteBatchInternal::InsertInto(
            &batch, column_family_memtables_.get(),
-            nullptr /* flush_scheduler */, true, log_number, this,
-            false /* concurrent_memtable_writes */, next_sequence,
-            &has_valid_writes, seq_per_batch_, batch_per_txn_);
+            nullptr /* flush_scheduler */, nullptr /* trim_history_scheduler*/,
+            true, log_number, this, false /* concurrent_memtable_writes */,
+            next_sequence, &has_valid_writes, seq_per_batch_, batch_per_txn_);
      }
      // If column family was not found, it might mean that the WAL write
      // batch references to the column family that was dropped after the
@@ -405,7 +407,7 @@ ArenaWrappedDBIter* DBImplSecondary::NewIteratorImpl(
    const ReadOptions& read_options, ColumnFamilyData* cfd,
    SequenceNumber snapshot, ReadCallback* read_callback) {
  assert(nullptr != cfd);
-  SuperVersion* super_version = cfd->GetReferencedSuperVersion(&mutex_);
+  SuperVersion* super_version = cfd->GetReferencedSuperVersion(this);
  auto db_iter = NewArenaWrappedDbIterator(
      env_, read_options, *cfd->ioptions(), super_version->mutable_cf_options,
      snapshot,
@@ -497,45 +499,61 @@ Status DBImplSecondary::TryCatchUpWithPrimary() {
  // read the manifest and apply new changes to the secondary instance
  std::unordered_set<ColumnFamilyData*> cfds_changed;
  JobContext job_context(0, true /*create_superversion*/);
-  InstrumentedMutexLock lock_guard(&mutex_);
-  s = static_cast<ReactiveVersionSet*>(versions_.get())
-          ->ReadAndApply(&mutex_, &manifest_reader_, &cfds_changed);
+  {
+    InstrumentedMutexLock lock_guard(&mutex_);
+    s = static_cast_with_check<ReactiveVersionSet>(versions_.get())
+            ->ReadAndApply(&mutex_, &manifest_reader_, &cfds_changed);

-  ROCKS_LOG_INFO(immutable_db_options_.info_log, "Last sequence is %" PRIu64,
-                 static_cast<uint64_t>(versions_->LastSequence()));
-  for (ColumnFamilyData* cfd : cfds_changed) {
-    if (cfd->IsDropped()) {
-      ROCKS_LOG_DEBUG(immutable_db_options_.info_log, "[%s] is dropped\n",
-                      cfd->GetName().c_str());
-      continue;
+    ROCKS_LOG_INFO(immutable_db_options_.info_log, "Last sequence is %" PRIu64,
+                   static_cast<uint64_t>(versions_->LastSequence()));
+    for (ColumnFamilyData* cfd : cfds_changed) {
+      if (cfd->IsDropped()) {
+        ROCKS_LOG_DEBUG(immutable_db_options_.info_log, "[%s] is dropped\n",
+                        cfd->GetName().c_str());
+        continue;
+      }
+      VersionStorageInfo::LevelSummaryStorage tmp;
+      ROCKS_LOG_DEBUG(immutable_db_options_.info_log,
+                      "[%s] Level summary: %s\n", cfd->GetName().c_str(),
+                      cfd->current()->storage_info()->LevelSummary(&tmp));
    }
-    VersionStorageInfo::LevelSummaryStorage tmp;
-    ROCKS_LOG_DEBUG(immutable_db_options_.info_log, "[%s] Level summary: %s\n",
-                    cfd->GetName().c_str(),
-                    cfd->current()->storage_info()->LevelSummary(&tmp));
-  }

-  // list wal_dir to discover new WALs and apply new changes to the secondary
-  // instance
-  if (s.ok()) {
-    s = FindAndRecoverLogFiles(&cfds_changed, &job_context);
-  }
-  if (s.IsPathNotFound()) {
-    ROCKS_LOG_INFO(immutable_db_options_.info_log,
-                   "Secondary tries to read WAL, but WAL file(s) have already "
-                   "been purged by primary.");
-    s = Status::OK();
-  }
-  if (s.ok()) {
-    for (auto cfd : cfds_changed) {
-      cfd->imm()->RemoveOldMemTables(cfd->GetLogNumber(),
-                                     &job_context.memtables_to_free);
-      auto& sv_context = job_context.superversion_contexts.back();
-      cfd->InstallSuperVersion(&sv_context, &mutex_);
-      sv_context.NewSuperVersion();
+    // list wal_dir to discover new WALs and apply new changes to the secondary
+    // instance
+    if (s.ok()) {
+      s = FindAndRecoverLogFiles(&cfds_changed, &job_context);
+    }
+    if (s.IsPathNotFound()) {
+      ROCKS_LOG_INFO(
+          immutable_db_options_.info_log,
+          "Secondary tries to read WAL, but WAL file(s) have already "
+          "been purged by primary.");
+      s = Status::OK();
+    }
+    if (s.ok()) {
+      for (auto cfd : cfds_changed) {
+        cfd->imm()->RemoveOldMemTables(cfd->GetLogNumber(),
+                                       &job_context.memtables_to_free);
+        auto& sv_context = job_context.superversion_contexts.back();
+        cfd->InstallSuperVersion(&sv_context, &mutex_);
+        sv_context.NewSuperVersion();
+      }
    }
-    job_context.Clean();
  }
+  job_context.Clean();
+
+  // Cleanup unused, obsolete files.
+  JobContext purge_files_job_context(0);
+  {
+    InstrumentedMutexLock lock_guard(&mutex_);
+    // Currently, secondary instance does not own the database files, thus it
+    // is unnecessary for the secondary to force full scan.
+    FindObsoleteFiles(&purge_files_job_context, /*force=*/false);
+  }
+  if (purge_files_job_context.HaveSomethingToDelete()) {
+    PurgeObsoleteFiles(purge_files_job_context);
+  }
+  purge_files_job_context.Clean();
  return s;
 }

@@ -583,13 +601,12 @@ Status DB::OpenAsSecondary(
  handles->clear();
  DBImplSecondary* impl = new DBImplSecondary(tmp_opts, dbname);
  impl->versions_.reset(new ReactiveVersionSet(
-      dbname, &impl->immutable_db_options_, impl->env_options_,
+      dbname, &impl->immutable_db_options_, impl->file_options_,
      impl->table_cache_.get(), impl->write_buffer_manager_,
      &impl->write_controller_));
  impl->column_family_memtables_.reset(
      new ColumnFamilyMemTablesImpl(impl->versions_->GetColumnFamilySet()));
-  impl->wal_in_db_path_ =
-      IsWalDirSameAsDBPath(&impl->immutable_db_options_);
+  impl->wal_in_db_path_ = IsWalDirSameAsDBPath(&impl->immutable_db_options_);

  impl->mutex_.Lock();
  s = impl->Recover(column_families, true, false, false);
@@ -172,6 +172,24 @@ class DBImplSecondary : public DBImpl {
    return Status::NotSupported("Not supported operation in secondary mode.");
  }

+  using DBImpl::SetDBOptions;
+  Status SetDBOptions(const std::unordered_map<std::string, std::string>&
+                      /*options_map*/) override {
+    // Currently not supported because changing certain options may cause
+    // flush/compaction.
+    return Status::NotSupported("Not supported operation in secondary mode.");
+  }
+
+  using DBImpl::SetOptions;
+  Status SetOptions(
+      ColumnFamilyHandle* /*cfd*/,
+      const std::unordered_map<std::string, std::string>& /*options_map*/)
+      override {
+    // Currently not supported because changing certain options may cause
+    // flush/compaction and/or write to MANIFEST.
+    return Status::NotSupported("Not supported operation in secondary mode.");
+  }
+
  using DBImpl::SyncWAL;
  Status SyncWAL() override {
    return Status::NotSupported("Not supported operation in secondary mode.");
@@ -269,6 +287,14 @@ class DBImplSecondary : public DBImpl {
    return s;
  }

+  bool OwnTablesAndLogs() const override {
+    // Currently, the secondary instance does not own the database files. It
+    // simply opens the files of the primary instance and tracks their file
+    // descriptors until they become obsolete. In the future, the secondary may
+    // create links to database files. OwnTablesAndLogs will return true then.
+    return false;
+  }
+
 private:
  friend class DB;

@@ -131,6 +131,7 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
                              log_used, log_ref, &seq, sub_batch_cnt,
                              pre_release_callback, kDoAssignOrder,
                              kDoPublishLastSeq, disable_memtable);
+    TEST_SYNC_POINT("DBImpl::WriteImpl:UnorderedWriteAfterWriteWAL");
    if (!status.ok()) {
      return status;
    }
@@ -138,6 +139,7 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
      *seq_used = seq;
    }
    if (!disable_memtable) {
+      TEST_SYNC_POINT("DBImpl::WriteImpl:BeforeUnorderedWriteMemtable");
      status = UnorderedWriteMemtable(write_options, my_batch, callback,
                                      log_ref, seq, sub_batch_cnt);
    }
@@ -171,9 +173,10 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
          versions_->GetColumnFamilySet());
      w.status = WriteBatchInternal::InsertInto(
          &w, w.sequence, &column_family_memtables, &flush_scheduler_,
+          &trim_history_scheduler_,
          write_options.ignore_missing_column_families, 0 /*log_number*/, this,
          true /*concurrent_memtable_writes*/, seq_per_batch_, w.batch_cnt,
-          batch_per_txn_);
+          batch_per_txn_, write_options.memtable_insert_hint_per_batch);

      PERF_TIMER_START(write_pre_and_post_process_time);
    }
@@ -293,18 +296,19 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
    // We're optimistic, updating the stats before we successfully
    // commit.  That lets us release our leader status early.
    auto stats = default_cf_internal_stats_;
-    stats->AddDBStats(InternalStats::NUMBER_KEYS_WRITTEN, total_count,
+    stats->AddDBStats(InternalStats::kIntStatsNumKeysWritten, total_count,
                      concurrent_update);
    RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
-    stats->AddDBStats(InternalStats::BYTES_WRITTEN, total_byte_size,
+    stats->AddDBStats(InternalStats::kIntStatsBytesWritten, total_byte_size,
                      concurrent_update);
    RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
-    stats->AddDBStats(InternalStats::WRITE_DONE_BY_SELF, 1, concurrent_update);
+    stats->AddDBStats(InternalStats::kIntStatsWriteDoneBySelf, 1,
+                      concurrent_update);
    RecordTick(stats_, WRITE_DONE_BY_SELF);
    auto write_done_by_other = write_group.size - 1;
    if (write_done_by_other > 0) {
-      stats->AddDBStats(InternalStats::WRITE_DONE_BY_OTHER, write_done_by_other,
-                        concurrent_update);
+      stats->AddDBStats(InternalStats::kIntStatsWriteDoneByOther,
+                        write_done_by_other, concurrent_update);
      RecordTick(stats_, WRITE_DONE_BY_OTHER, write_done_by_other);
    }
    RecordInHistogram(stats_, BYTES_PER_WRITE, total_byte_size);
@@ -375,7 +379,8 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
        // w.sequence will be set inside InsertInto
        w.status = WriteBatchInternal::InsertInto(
            write_group, current_sequence, column_family_memtables_.get(),
-            &flush_scheduler_, write_options.ignore_missing_column_families,
+            &flush_scheduler_, &trim_history_scheduler_,
+            write_options.ignore_missing_column_families,
            0 /*recovery_log_number*/, this, parallel, seq_per_batch_,
            batch_per_txn_);
      } else {
@@ -391,9 +396,11 @@ Status DBImpl::WriteImpl(const WriteOptions& write_options,
          assert(w.sequence == current_sequence);
          w.status = WriteBatchInternal::InsertInto(
              &w, w.sequence, &column_family_memtables, &flush_scheduler_,
+              &trim_history_scheduler_,
              write_options.ignore_missing_column_families, 0 /*log_number*/,
              this, true /*concurrent_memtable_writes*/, seq_per_batch_,
-              w.batch_cnt, batch_per_txn_);
+              w.batch_cnt, batch_per_txn_,
+              write_options.memtable_insert_hint_per_batch);
        }
      }
      if (seq_used != nullptr) {
@@ -500,9 +507,9 @@ Status DBImpl::PipelinedWriteImpl(const WriteOptions& write_options,
    }

    auto stats = default_cf_internal_stats_;
-    stats->AddDBStats(InternalStats::NUMBER_KEYS_WRITTEN, total_count);
+    stats->AddDBStats(InternalStats::kIntStatsNumKeysWritten, total_count);
    RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
-    stats->AddDBStats(InternalStats::BYTES_WRITTEN, total_byte_size);
+    stats->AddDBStats(InternalStats::kIntStatsBytesWritten, total_byte_size);
    RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
    RecordInHistogram(stats_, BYTES_PER_WRITE, total_byte_size);

@@ -510,10 +517,10 @@ Status DBImpl::PipelinedWriteImpl(const WriteOptions& write_options,

    if (w.status.ok() && !write_options.disableWAL) {
      PERF_TIMER_GUARD(write_wal_time);
-      stats->AddDBStats(InternalStats::WRITE_DONE_BY_SELF, 1);
+      stats->AddDBStats(InternalStats::kIntStatsWriteDoneBySelf, 1);
      RecordTick(stats_, WRITE_DONE_BY_SELF, 1);
      if (wal_write_group.size > 1) {
-        stats->AddDBStats(InternalStats::WRITE_DONE_BY_OTHER,
+        stats->AddDBStats(InternalStats::kIntStatsWriteDoneByOther,
                          wal_write_group.size - 1);
        RecordTick(stats_, WRITE_DONE_BY_OTHER, wal_write_group.size - 1);
      }
@@ -545,9 +552,9 @@ Status DBImpl::PipelinedWriteImpl(const WriteOptions& write_options,
    } else {
      memtable_write_group.status = WriteBatchInternal::InsertInto(
          memtable_write_group, w.sequence, column_family_memtables_.get(),
-          &flush_scheduler_, write_options.ignore_missing_column_families,
-          0 /*log_number*/, this, false /*concurrent_memtable_writes*/,
-          seq_per_batch_, batch_per_txn_);
+          &flush_scheduler_, &trim_history_scheduler_,
+          write_options.ignore_missing_column_families, 0 /*log_number*/, this,
+          false /*concurrent_memtable_writes*/, seq_per_batch_, batch_per_txn_);
      versions_->SetLastSequence(memtable_write_group.last_sequence);
      write_thread_.ExitAsMemTableWriter(&w, memtable_write_group);
    }
@@ -559,8 +566,10 @@ Status DBImpl::PipelinedWriteImpl(const WriteOptions& write_options,
        versions_->GetColumnFamilySet());
    w.status = WriteBatchInternal::InsertInto(
        &w, w.sequence, &column_family_memtables, &flush_scheduler_,
-        write_options.ignore_missing_column_families, 0 /*log_number*/, this,
-        true /*concurrent_memtable_writes*/);
+        &trim_history_scheduler_, write_options.ignore_missing_column_families,
+        0 /*log_number*/, this, true /*concurrent_memtable_writes*/,
+        false /*seq_per_batch*/, 0 /*batch_cnt*/, true /*batch_per_txn*/,
+        write_options.memtable_insert_hint_per_batch);
    if (write_thread_.CompleteParallelMemTableWriter(&w)) {
      MemTableInsertStatusCheck(w.status);
      versions_->SetLastSequence(w.write_group->last_sequence);
@@ -590,15 +599,17 @@ Status DBImpl::UnorderedWriteMemtable(const WriteOptions& write_options,
    w.sequence = seq;
    size_t total_count = WriteBatchInternal::Count(my_batch);
    InternalStats* stats = default_cf_internal_stats_;
-    stats->AddDBStats(InternalStats::NUMBER_KEYS_WRITTEN, total_count);
+    stats->AddDBStats(InternalStats::kIntStatsNumKeysWritten, total_count);
    RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);

    ColumnFamilyMemTablesImpl column_family_memtables(
        versions_->GetColumnFamilySet());
    w.status = WriteBatchInternal::InsertInto(
        &w, w.sequence, &column_family_memtables, &flush_scheduler_,
-        write_options.ignore_missing_column_families, 0 /*log_number*/, this,
-        true /*concurrent_memtable_writes*/, seq_per_batch_, sub_batch_cnt);
+        &trim_history_scheduler_, write_options.ignore_missing_column_families,
+        0 /*log_number*/, this, true /*concurrent_memtable_writes*/,
+        seq_per_batch_, sub_batch_cnt, true /*batch_per_txn*/,
+        write_options.memtable_insert_hint_per_batch);

    WriteStatusCheck(w.status);
    if (write_options.disableWAL) {
@@ -699,15 +710,16 @@ Status DBImpl::WriteImplWALOnly(
  // We're optimistic, updating the stats before we successfully
  // commit.  That lets us release our leader status early.
  auto stats = default_cf_internal_stats_;
-  stats->AddDBStats(InternalStats::BYTES_WRITTEN, total_byte_size,
+  stats->AddDBStats(InternalStats::kIntStatsBytesWritten, total_byte_size,
                    concurrent_update);
  RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
-  stats->AddDBStats(InternalStats::WRITE_DONE_BY_SELF, 1, concurrent_update);
+  stats->AddDBStats(InternalStats::kIntStatsWriteDoneBySelf, 1,
+                    concurrent_update);
  RecordTick(stats_, WRITE_DONE_BY_SELF);
  auto write_done_by_other = write_group.size - 1;
  if (write_done_by_other > 0) {
-    stats->AddDBStats(InternalStats::WRITE_DONE_BY_OTHER, write_done_by_other,
-                      concurrent_update);
+    stats->AddDBStats(InternalStats::kIntStatsWriteDoneByOther,
+                      write_done_by_other, concurrent_update);
    RecordTick(stats_, WRITE_DONE_BY_OTHER, write_done_by_other);
  }
  RecordInHistogram(stats_, BYTES_PER_WRITE, total_byte_size);
@@ -856,6 +868,10 @@ Status DBImpl::PreprocessWrite(const WriteOptions& write_options,
    status = HandleWriteBufferFull(write_context);
  }

+  if (UNLIKELY(status.ok() && !trim_history_scheduler_.Empty())) {
+    status = TrimMemtableHistory(write_context);
+  }
+
  if (UNLIKELY(status.ok() && !flush_scheduler_.Empty())) {
    WaitForPendingWrites();
    status = ScheduleFlushes(write_context);
@@ -1035,12 +1051,12 @@ Status DBImpl::WriteToWAL(const WriteThread::WriteGroup& write_group,
  if (status.ok()) {
    auto stats = default_cf_internal_stats_;
    if (need_log_sync) {
-      stats->AddDBStats(InternalStats::WAL_FILE_SYNCED, 1);
+      stats->AddDBStats(InternalStats::kIntStatsWalFileSynced, 1);
      RecordTick(stats_, WAL_FILE_SYNCED);
    }
-    stats->AddDBStats(InternalStats::WAL_FILE_BYTES, log_size);
+    stats->AddDBStats(InternalStats::kIntStatsWalFileBytes, log_size);
    RecordTick(stats_, WAL_FILE_BYTES, log_size);
-    stats->AddDBStats(InternalStats::WRITE_WITH_WAL, write_with_wal);
+    stats->AddDBStats(InternalStats::kIntStatsWriteWithWal, write_with_wal);
    RecordTick(stats_, WRITE_WITH_WAL, write_with_wal);
  }
  return status;
@@ -1086,9 +1102,10 @@ Status DBImpl::ConcurrentWriteToWAL(const WriteThread::WriteGroup& write_group,
  if (status.ok()) {
    const bool concurrent = true;
    auto stats = default_cf_internal_stats_;
-    stats->AddDBStats(InternalStats::WAL_FILE_BYTES, log_size, concurrent);
+    stats->AddDBStats(InternalStats::kIntStatsWalFileBytes, log_size,
+                      concurrent);
    RecordTick(stats_, WAL_FILE_BYTES, log_size);
-    stats->AddDBStats(InternalStats::WRITE_WITH_WAL, write_with_wal,
+    stats->AddDBStats(InternalStats::kIntStatsWriteWithWal, write_with_wal,
                      concurrent);
    RecordTick(stats_, WRITE_WITH_WAL, write_with_wal);
  }
@@ -1112,9 +1129,9 @@ Status DBImpl::WriteRecoverableState() {
    WriteBatchInternal::SetSequence(&cached_recoverable_state_, seq + 1);
    auto status = WriteBatchInternal::InsertInto(
        &cached_recoverable_state_, column_family_memtables_.get(),
-        &flush_scheduler_, true, 0 /*recovery_log_number*/, this,
-        false /* concurrent_memtable_writes */, &next_seq, &dont_care_bool,
-        seq_per_batch_);
+        &flush_scheduler_, &trim_history_scheduler_, true,
+        0 /*recovery_log_number*/, this, false /* concurrent_memtable_writes */,
+        &next_seq, &dont_care_bool, seq_per_batch_);
    auto last_seq = next_seq - 1;
    if (two_write_queues_) {
      versions_->FetchAddLastAllocatedSequence(last_seq - seq);
@@ -1231,14 +1248,23 @@ Status DBImpl::SwitchWAL(WriteContext* write_context) {
    }
    MaybeFlushStatsCF(&cfds);
  }
+  WriteThread::Writer nonmem_w;
+  if (two_write_queues_) {
+    nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
+  }
+
  for (const auto cfd : cfds) {
    cfd->Ref();
    status = SwitchMemtable(cfd, write_context);
-    cfd->Unref();
+    cfd->UnrefAndTryDelete();
    if (!status.ok()) {
      break;
    }
  }
+  if (two_write_queues_) {
+    nonmem_write_thread_.ExitUnbatched(&nonmem_w);
+  }
+
  if (status.ok()) {
    if (immutable_db_options_.atomic_flush) {
      AssignAtomicFlushSeq(cfds);
@@ -1299,17 +1325,25 @@ Status DBImpl::HandleWriteBufferFull(WriteContext* write_context) {
    MaybeFlushStatsCF(&cfds);
  }

+  WriteThread::Writer nonmem_w;
+  if (two_write_queues_) {
+    nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
+  }
  for (const auto cfd : cfds) {
    if (cfd->mem()->IsEmpty()) {
      continue;
    }
    cfd->Ref();
    status = SwitchMemtable(cfd, write_context);
-    cfd->Unref();
+    cfd->UnrefAndTryDelete();
    if (!status.ok()) {
      break;
    }
  }
+  if (two_write_queues_) {
+    nonmem_write_thread_.ExitUnbatched(&nonmem_w);
+  }
+
  if (status.ok()) {
    if (immutable_db_options_.atomic_flush) {
      AssignAtomicFlushSeq(cfds);
@@ -1390,8 +1424,8 @@ Status DBImpl::DelayWrite(uint64_t num_bytes,
  }
  assert(!delayed || !write_options.no_slowdown);
  if (delayed) {
-    default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_STALL_MICROS,
-                                           time_delayed);
+    default_cf_internal_stats_->AddDBStats(
+        InternalStats::kIntStatsWriteStallMicros, time_delayed);
    RecordTick(stats_, STALL_MICROS, time_delayed);
  }

@@ -1474,6 +1508,32 @@ void DBImpl::MaybeFlushStatsCF(autovector<ColumnFamilyData*>* cfds) {
  }
 }

+Status DBImpl::TrimMemtableHistory(WriteContext* context) {
+  autovector<ColumnFamilyData*> cfds;
+  ColumnFamilyData* tmp_cfd;
+  while ((tmp_cfd = trim_history_scheduler_.TakeNextColumnFamily()) !=
+         nullptr) {
+    cfds.push_back(tmp_cfd);
+  }
+  for (auto& cfd : cfds) {
+    autovector<MemTable*> to_delete;
+    cfd->imm()->TrimHistory(&to_delete, cfd->mem()->ApproximateMemoryUsage());
+    if (!to_delete.empty()) {
+      for (auto m : to_delete) {
+        delete m;
+      }
+      context->superversion_context.NewSuperVersion();
+      assert(context->superversion_context.new_superversion.get() != nullptr);
+      cfd->InstallSuperVersion(&context->superversion_context, &mutex_);
+    }
+
+    if (cfd->UnrefAndTryDelete()) {
+      cfd = nullptr;
+    }
+  }
+  return Status::OK();
+}
+
 Status DBImpl::ScheduleFlushes(WriteContext* context) {
  autovector<ColumnFamilyData*> cfds;
  if (immutable_db_options_.atomic_flush) {
@@ -1490,18 +1550,27 @@ Status DBImpl::ScheduleFlushes(WriteContext* context) {
    MaybeFlushStatsCF(&cfds);
  }
  Status status;
+  WriteThread::Writer nonmem_w;
+  if (two_write_queues_) {
+    nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
+  }
+
  for (auto& cfd : cfds) {
    if (!cfd->mem()->IsEmpty()) {
      status = SwitchMemtable(cfd, context);
    }
-    if (cfd->Unref()) {
-      delete cfd;
+    if (cfd->UnrefAndTryDelete()) {
      cfd = nullptr;
    }
    if (!status.ok()) {
      break;
    }
  }
+
+  if (two_write_queues_) {
+    nonmem_write_thread_.ExitUnbatched(&nonmem_w);
+  }
+
  if (status.ok()) {
    if (immutable_db_options_.atomic_flush) {
      AssignAtomicFlushSeq(cfds);
@@ -1532,15 +1601,11 @@ void DBImpl::NotifyOnMemTableSealed(ColumnFamilyData* /*cfd*/,

 // REQUIRES: mutex_ is held
 // REQUIRES: this thread is currently at the front of the writer queue
+// REQUIRES: this thread is currently at the front of the 2nd writer queue if
+// two_write_queues_ is true (This is to simplify the reasoning.)
 Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
  mutex_.AssertHeld();
  WriteThread::Writer nonmem_w;
-  if (two_write_queues_) {
-    // SwitchMemtable is a rare event. To simply the reasoning, we make sure
-    // that there is no concurrent thread writing to WAL.
-    nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
-  }
-
  std::unique_ptr<WritableFile> lfile;
  log::Writer* new_log = nullptr;
  MemTable* new_mem = nullptr;
@@ -1552,16 +1617,6 @@ Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
    return s;
  }

-  // In case of pipelined write is enabled, wait for all pending memtable
-  // writers.
-  if (immutable_db_options_.enable_pipelined_write) {
-    // Memtable writers may call DB::Get in case max_successive_merges > 0,
-    // which may lock mutex. Unlocking mutex here to avoid deadlock.
-    mutex_.Unlock();
-    write_thread_.WaitForMemTableWriters();
-    mutex_.Lock();
-  }
-
  // Attempt to switch to a new memtable and trigger flush of old.
  // Do this without holding the dbmutex lock.
  assert(versions_->prev_log_number() == 0);
@@ -1657,10 +1712,6 @@ Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
    error_handler_.SetBGError(s, BackgroundErrorReason::kMemTable);
    // Read back bg_error in order to get the right severity
    s = error_handler_.GetBGError();
-
-    if (two_write_queues_) {
-      nonmem_write_thread_.ExitUnbatched(&nonmem_w);
-    }
    return s;
  }

@@ -1691,9 +1742,6 @@ Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
  NotifyOnMemTableSealed(cfd, memtable_info);
  mutex_.Lock();
 #endif  // ROCKSDB_LITE
-  if (two_write_queues_) {
-    nonmem_write_thread_.ExitUnbatched(&nonmem_w);
-  }
  return s;
 }

@@ -195,6 +195,90 @@ TEST_F(DBSecondaryTest, OpenAsSecondary) {
  verify_db_func("new_foo_value", "new_bar_value");
 }

+namespace {
+class TraceFileEnv : public EnvWrapper {
+ public:
+  explicit TraceFileEnv(Env* _target) : EnvWrapper(_target) {}
+  Status NewRandomAccessFile(const std::string& f,
+                             std::unique_ptr<RandomAccessFile>* r,
+                             const EnvOptions& env_options) override {
+    class TracedRandomAccessFile : public RandomAccessFile {
+     public:
+      TracedRandomAccessFile(std::unique_ptr<RandomAccessFile>&& target,
+                             std::atomic<int>& counter)
+          : target_(std::move(target)), files_closed_(counter) {}
+      ~TracedRandomAccessFile() override {
+        files_closed_.fetch_add(1, std::memory_order_relaxed);
+      }
+      Status Read(uint64_t offset, size_t n, Slice* result,
+                  char* scratch) const override {
+        return target_->Read(offset, n, result, scratch);
+      }
+
+     private:
+      std::unique_ptr<RandomAccessFile> target_;
+      std::atomic<int>& files_closed_;
+    };
+    Status s = target()->NewRandomAccessFile(f, r, env_options);
+    if (s.ok()) {
+      r->reset(new TracedRandomAccessFile(std::move(*r), files_closed_));
+    }
+    return s;
+  }
+
+  int files_closed() const {
+    return files_closed_.load(std::memory_order_relaxed);
+  }
+
+ private:
+  std::atomic<int> files_closed_{0};
+};
+}  // namespace
+
+TEST_F(DBSecondaryTest, SecondaryCloseFiles) {
+  Options options;
+  options.env = env_;
+  options.max_open_files = 1;
+  options.disable_auto_compactions = true;
+  Reopen(options);
+  Options options1;
+  std::unique_ptr<Env> traced_env(new TraceFileEnv(env_));
+  options1.env = traced_env.get();
+  OpenSecondary(options1);
+
+  static const auto verify_db = [&]() {
+    std::unique_ptr<Iterator> iter1(dbfull()->NewIterator(ReadOptions()));
+    std::unique_ptr<Iterator> iter2(db_secondary_->NewIterator(ReadOptions()));
+    for (iter1->SeekToFirst(), iter2->SeekToFirst();
+         iter1->Valid() && iter2->Valid(); iter1->Next(), iter2->Next()) {
+      ASSERT_EQ(iter1->key(), iter2->key());
+      ASSERT_EQ(iter1->value(), iter2->value());
+    }
+    ASSERT_FALSE(iter1->Valid());
+    ASSERT_FALSE(iter2->Valid());
+  };
+
+  ASSERT_OK(Put("a", "value"));
+  ASSERT_OK(Put("c", "value"));
+  ASSERT_OK(Flush());
+  ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
+  verify_db();
+
+  ASSERT_OK(Put("b", "value"));
+  ASSERT_OK(Put("d", "value"));
+  ASSERT_OK(Flush());
+  ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
+  verify_db();
+
+  ASSERT_OK(dbfull()->CompactRange(CompactRangeOptions(), nullptr, nullptr));
+  ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
+  ASSERT_EQ(2, static_cast<TraceFileEnv*>(traced_env.get())->files_closed());
+
+  Status s = db_secondary_->SetDBOptions({{"max_open_files", "-1"}});
+  ASSERT_TRUE(s.IsNotSupported());
+  CloseSecondary();
+}
+
 TEST_F(DBSecondaryTest, OpenAsSecondaryWALTailing) {
  Options options;
  options.env = env_;
@@ -605,9 +689,9 @@ TEST_F(DBSecondaryTest, SwitchWAL) {
 TEST_F(DBSecondaryTest, SwitchWALMultiColumnFamilies) {
  const int kNumKeysPerMemtable = 1;
  SyncPoint::GetInstance()->DisableProcessing();
-  SyncPoint::GetInstance()->LoadDependency({
-      {"DBImpl::BackgroundCallFlush:ContextCleanedUp",
-       "DBSecondaryTest::SwitchWALMultipleColumnFamilies:BeforeCatchUp"}});
+  SyncPoint::GetInstance()->LoadDependency(
+      {{"DBImpl::BackgroundCallFlush:ContextCleanedUp",
+        "DBSecondaryTest::SwitchWALMultipleColumnFamilies:BeforeCatchUp"}});
  SyncPoint::GetInstance()->EnableProcessing();
  const std::string kCFName1 = "pikachu";
  Options options;
@@ -662,7 +746,8 @@ TEST_F(DBSecondaryTest, SwitchWALMultiColumnFamilies) {
        Put(0 /*cf*/, "key" + std::to_string(k), "value" + std::to_string(k)));
    ASSERT_OK(
        Put(1 /*cf*/, "key" + std::to_string(k), "value" + std::to_string(k)));
-    TEST_SYNC_POINT("DBSecondaryTest::SwitchWALMultipleColumnFamilies:BeforeCatchUp");
+    TEST_SYNC_POINT(
+        "DBSecondaryTest::SwitchWALMultipleColumnFamilies:BeforeCatchUp");
    ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
    verify_db(dbfull(), handles_, db_secondary_, handles_secondary_);
    SyncPoint::GetInstance()->ClearTrace();
@@ -5,10 +5,10 @@

 #include "db/db_info_dumper.h"

-#include <cinttypes>
 #include <stdio.h>
-#include <string>
 #include <algorithm>
+#include <cinttypes>
+#include <string>
 #include <vector>

 #include "file/filename.h"