Fix the valgrind error

Summary: I this bug from valgrind report and found a place that may potentially leak memory. Test Plan: re-ran the valgrind and no error any more Reviewers: emayanke Reviewed By: emayanke CC: leveldb Differential Revision: https://reviews.facebook.net/D13959
Flush the log outside of lock
2026-11-06 11:02:36 -05:00 · 2013-11-07 15:46:48 -08:00 · 2013-11-07 11:31:56 -08:00 · 2013-11-06 20:45:49 -08:00 · 2013-11-06 18:46:28 -08:00 · 2013-11-06 15:40:26 -08:00
569 changed files with 18272 additions and 111770 deletions
@@ -1,18 +1,23 @@
 build_config.mk
+
 *.a
-*.o
+*.arc
+*.d
 *.dylib*
+*.gcda
+*.gcno
+*.o
 *.so
 *.so.*
 *_test
-*.arc
-*.d
-db_bench
-db_stress
+*_bench
+*_stress
+
 ldb
-leveldb_server
-leveldb_shell
 manifest_dump
 sst_dump
 util/build_version.cc
-db_repl_stress
+build_tools/VALGRIND_LOGS/
+coverage/COVERAGE_REPORT
+util/build_version.cc.tmp
+.gdbhistory
@@ -1,3 +1,11 @@
+BSD License
+
+For rocksdb software
+
+Copyright (c) 2013, Facebook, Inc.
+All rights reserved.
+---------------------------------------------------------------------
+
 Copyright (c) 2011 The LevelDB Authors. All rights reserved.

 Redistribution and use in source and binary forms, with or without
@@ -14,13 +14,13 @@ OPT += -O2 -fno-omit-frame-pointer -momit-leaf-frame-pointer
 #-----------------------------------------------

 # detect what platform we're building on
-$(shell ./build_detect_platform build_config.mk)
+$(shell (export ROCKSDB_ROOT=$(CURDIR); $(CURDIR)/build_tools/build_detect_platform $(CURDIR)/build_config.mk))
 # this file is generated by the previous line to set build flags and sources
 include build_config.mk

 WARNING_FLAGS = -Wall -Werror
 CFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CCFLAGS) $(OPT)
-CXXFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -std=gnu++0x
+CXXFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -std=gnu++0x -Woverloaded-virtual

 LDFLAGS += $(PLATFORM_LDFLAGS)

@@ -31,60 +31,70 @@ MEMENVOBJECTS = $(MEMENV_SOURCES:.cc=.o)
 TESTUTIL = ./util/testutil.o
 TESTHARNESS = ./util/testharness.o $(TESTUTIL)
 VALGRIND_ERROR = 2
-VALGRIND_DIR = VALGRIND_LOGS
+VALGRIND_DIR = build_tools/VALGRIND_LOGS
 VALGRIND_VER := $(join $(VALGRIND_VER),valgrind)
 VALGRIND_OPTS = --error-exitcode=$(VALGRIND_ERROR) --leak-check=full

 TESTS = \
+	table_stats_collector_test \
 	arena_test \
+	auto_roll_logger_test \
+	block_test \
 	bloom_test \
 	c_test \
 	cache_test \
 	coding_test \
-	histogram_test \
 	corruption_test \
 	crc32c_test \
 	db_test \
 	dbformat_test \
 	env_test \
+	blob_store_test \
+	filelock_test \
 	filename_test \
 	filter_block_test \
+	histogram_test \
 	log_test \
+	manual_compaction_test \
 	memenv_test \
-	skiplist_test \
-	table_test \
-	ttl_test \
-	block_test \
-	version_edit_test \
-	version_set_test \
-	reduce_levels_test \
-	write_batch_test \
-	auto_roll_logger_test \
-	filelock_test \
 	merge_test \
 	redis_test \
-	manual_compaction_test \
-	stringappend_test
+	reduce_levels_test \
+	simple_table_db_test \
+	skiplist_test \
+	stringappend_test \
+	table_test \
+	ttl_test \
+	version_edit_test \
+	version_set_test \
+	write_batch_test\
+	deletefile_test

 TOOLS = \
        sst_dump \
        db_stress \
        ldb \
-	db_repl_stress
+	db_repl_stress \
+	blob_store_bench

 PROGRAMS = db_bench signal_test $(TESTS) $(TOOLS)
-BENCHMARKS = db_bench_sqlite3 db_bench_tree_db
+BENCHMARKS = db_bench_sqlite3 db_bench_tree_db table_reader_bench

-LIBRARY = librocksdb.a
+# The library name is configurable since we are maintaining libraries of both
+# debug/release mode.
+LIBNAME = librocksdb
+LIBRARY = ${LIBNAME}.a
 MEMENVLIBRARY = libmemenv.a

 default: all

-# Should we build shared libraries?
+#-----------------------------------------------
+# Create platform independent shared libraries.
+#-----------------------------------------------
 ifneq ($(PLATFORM_SHARED_EXT),)

 ifneq ($(PLATFORM_SHARED_VERSIONED),true)
-SHARED1 = librocksdb.$(PLATFORM_SHARED_EXT)
+SHARED1 = ${LIBNAME}.$(PLATFORM_SHARED_EXT)
 SHARED2 = $(SHARED1)
 SHARED3 = $(SHARED1)
 SHARED = $(SHARED1)
@@ -92,7 +102,7 @@ else
 # Update db.h if you change these.
 SHARED_MAJOR = 2
 SHARED_MINOR = 0
-SHARED1 = librocksdb.$(PLATFORM_SHARED_EXT)
+SHARED1 = ${LIBNAME}.$(PLATFORM_SHARED_EXT)
 SHARED2 = $(SHARED1).$(SHARED_MAJOR)
 SHARED3 = $(SHARED1).$(SHARED_MAJOR).$(SHARED_MINOR)
 SHARED = $(SHARED1) $(SHARED2) $(SHARED3)
@@ -103,15 +113,25 @@ $(SHARED2): $(SHARED3)
 endif

 $(SHARED3):
-	$(CXX) $(LDFLAGS) $(PLATFORM_SHARED_LDFLAGS)$(SHARED2) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) $(SOURCES) -o $(SHARED3)
+	$(CXX) $(LDFLAGS) $(PLATFORM_SHARED_LDFLAGS)$(SHARED2) $(CXXFLAGS) $(COVERAGEFLAGS) $(PLATFORM_SHARED_CFLAGS) $(SOURCES) -o $(SHARED3)

 endif  # PLATFORM_SHARED_EXT

-all: $(SHARED) $(LIBRARY) $(PROGRAMS)
+all: $(LIBRARY) $(PROGRAMS)
+
+.PHONY: blackbox_crash_test check clean coverage crash_test ldb_tests \
+	release tags valgrind_check whitebox_crash_test

 release:
-	make clean
-	OPT=-DNDEBUG make -j32
+	$(MAKE) clean
+	OPT=-DNDEBUG $(MAKE) -j32
+
+coverage:
+	$(MAKE) clean
+	COVERAGEFLAGS="-fprofile-arcs -ftest-coverage" LDFLAGS+="-lgcov" $(MAKE) all check
+	(cd coverage; ./coverage_test.sh)
+	# Delete intermediate files
+	find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" | xargs --no-run-if-empty rm

 check: all $(PROGRAMS) $(TESTS) $(TOOLS) ldb_tests
 	for t in $(TESTS); do echo "***** Running $$t"; ./$$t || exit 1; done
@@ -128,6 +148,7 @@ whitebox_crash_test: db_stress
 	python -u tools/db_crashtest2.py

 valgrind_check: all $(PROGRAMS) $(TESTS)
+	mkdir -p $(VALGRIND_DIR)
 	echo TESTS THAT HAVE VALGRIND ERRORS > $(VALGRIND_DIR)/valgrind_failed_tests; \
 	echo TIMES in seconds TAKEN BY TESTS ON VALGRIND > $(VALGRIND_DIR)/valgrind_tests_times; \
 	for t in $(filter-out skiplist_test,$(TESTS)); do \
@@ -141,140 +162,169 @@ valgrind_check: all $(PROGRAMS) $(TESTS)
 	done

 clean:
-	-rm -f $(PROGRAMS) $(BENCHMARKS) $(LIBRARY) $(SHARED) $(MEMENVLIBRARY) $(THRIFTSERVER) build_config.mk
+	-rm -f $(PROGRAMS) $(BENCHMARKS) $(LIBRARY) $(SHARED) $(MEMENVLIBRARY) build_config.mk
 	-rm -rf ios-x86/* ios-arm/*
-	-for x in `find . -name "*.[od]"`; do rm $$x; done
+	-find . -name "*.[od]" | xargs --no-run-if-empty rm
+	-find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" | xargs --no-run-if-empty rm
+tags:
+	ctags * -R
+	cscope -b `find . -name '*.cc'` `find . -name '*.h'`

+# ---------------------------------------------------------------------------
+# 	Unit tests and tools
+# ---------------------------------------------------------------------------
 $(LIBRARY): $(LIBOBJECTS)
 	rm -f $@
 	$(AR) -rs $@ $(LIBOBJECTS)

-
 db_bench: db/db_bench.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) db/db_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)
+	$(CXX) db/db_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)

 db_stress: tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)
+	$(CXX) tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)

 db_repl_stress: tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)
+	$(CXX) tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+
+blob_store_bench: tools/blob_store_bench.o $(LIBOBJECTS) $(TESTUTIL)
+	$(CXX) tools/blob_store_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)

 db_bench_sqlite3: doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lsqlite3
+	$(CXX) doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lsqlite3 $(COVERAGEFLAGS)

 db_bench_tree_db: doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lkyotocabinet
+	$(CXX) doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lkyotocabinet $(COVERAGEFLAGS)

 signal_test: util/signal_test.o $(LIBOBJECTS)
-	$(CXX) util/signal_test.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/signal_test.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 arena_test: util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+table_stats_collector_test: db/table_stats_collector_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/table_stats_collector_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 bloom_test: util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 c_test: db/c_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 cache_test: util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 coding_test: util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+blob_store_test: util/blob_store_test.o $(LIBOBJECTS) $(TESTHARNESS) $(TESTUTIL)
+	$(CXX) util/blob_store_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)

 stringappend_test: utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 redis_test: utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 histogram_test: util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS)
+	$(CXX) util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)

 corruption_test: db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 crc32c_test: util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 db_test: db/db_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+simple_table_db_test: db/simple_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/simple_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+table_reader_bench: table/table_reader_bench.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) table/table_reader_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+perf_context_test: db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+
+prefix_test: db/prefix_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/prefix_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 ttl_test: utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)
+	$(CXX) utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)

 dbformat_test: db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 env_test: util/env_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/env_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/env_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 filename_test: db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 filter_block_test: table/filter_block_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) table/filter_block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) table/filter_block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 log_test: db/log_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/log_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/log_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 table_test: table/table_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) table/table_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) table/table_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 block_test: table/block_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) table/block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) table/block_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 skiplist_test: db/skiplist_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/skiplist_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/skiplist_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 version_edit_test: db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 version_set_test: db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 reduce_levels_test: tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 write_batch_test: db/write_batch_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/write_batch_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/write_batch_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 merge_test: db/merge_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) db/merge_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) db/merge_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+deletefile_test: db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)

 $(MEMENVLIBRARY) : $(MEMENVOBJECTS)
 	rm -f $@
 	$(AR) -rs $@ $(MEMENVOBJECTS)

 memenv_test : helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS)
-	$(CXX) helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 manual_compaction_test: util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 rocksdb_shell: tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o tools/shell/ShellContext.h tools/shell/ShellState.h tools/shell/DBClientProxy.h $(LIBOBJECTS)
-	$(CXX) tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) tools/shell/ShellContext.o tools/shell/ShellState.o tools/shell/LeveldbShell.o tools/shell/DBClientProxy.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 DBClientProxy_test: tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY)
-	$(CXX) tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY) $(EXEC_LDFLAGS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS)
+	$(CXX) tools/shell/test/DBClientProxyTest.o tools/shell/DBClientProxy.o $(LIBRARY) $(EXEC_LDFLAGS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)

 filelock_test: util/filelock_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/filelock_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/filelock_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 auto_roll_logger_test: util/auto_roll_logger_test.o $(LIBOBJECTS) $(TESTHARNESS)
-	$(CXX) util/auto_roll_logger_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) util/auto_roll_logger_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 sst_dump: tools/sst_dump.o $(LIBOBJECTS)
-	$(CXX) tools/sst_dump.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) tools/sst_dump.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

 ldb: tools/ldb.o $(LIBOBJECTS)
-	$(CXX) tools/ldb.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+	$(CXX) tools/ldb.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)

-.PHONY: tags
-tags:
-	ctags `find . -name '*.cc'` `find . -name '*.h'`
-	cscope -b `find . -name '*.cc'` `find . -name '*.h'`
+# ---------------------------------------------------------------------------
+#  	Platform-specific compilation
+# ---------------------------------------------------------------------------

 ifeq ($(PLATFORM), IOS)
 # For iOS, create universal object files to be used on both the simulator and
@@ -286,9 +336,9 @@ IOSVERSION=$(shell defaults read $(PLATFORMSROOT)/iPhoneOS.platform/versionCFBun

 .cc.o:
 	mkdir -p ios-x86/$(dir $@)
-	$(SIMULATORROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -c $< -o ios-x86/$@
+	$(SIMULATORROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -c $< -o ios-x86/$@ $(COVERAGEFLAGS)
 	mkdir -p ios-arm/$(dir $@)
-	$(DEVICEROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -c $< -o ios-arm/$@
+	$(DEVICEROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -c $< -o ios-arm/$@ $(COVERAGEFLAGS)
 	lipo ios-x86/$@ ios-arm/$@ -create -output $@

 .c.o:
@@ -300,17 +350,26 @@ IOSVERSION=$(shell defaults read $(PLATFORMSROOT)/iPhoneOS.platform/versionCFBun

 else
 .cc.o:
-	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -c $< -o $@
+	$(CXX) $(CXXFLAGS) -c $< -o $@ $(COVERAGEFLAGS)

 .c.o:
-	$(CC) $(CFLAGS) $(PLATFORM_SHARED_CFLAGS) -c $< -o $@
+	$(CC) $(CFLAGS) -c $< -o $@
 endif

+# ---------------------------------------------------------------------------
+#  	Source files dependencies detection
+# ---------------------------------------------------------------------------
+
+# Add proper dependency support so changing a .h file forces a .cc file to
+# rebuild.
+
+# The .d file indicates .cc file's dependencies on .h files. We generate such
+# dependency by g++'s -MM option, whose output is a make dependency rule.
+# The sed command makes sure the "target" file in the generated .d file has
+# the correct path prefix.
 %.d: %.cc
-	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -MM $< -o $*.d
-	@cp -f $*.d $*.d.tmp
-	@sed -e 's|.*:|$*.o:|' < $*.d.tmp > $*.d
-	@rm -f $*.d.tmp
+	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -MM $< -o $@
+	@sed -i -e 's|.*:|$*.o:|' $@

 DEPFILES = $(filter-out util/build_version.d,$(SOURCES:.cc=.d))

@@ -319,4 +378,3 @@ depend: $(DEPFILES)
 ifneq ($(MAKECMDGOALS),clean)
 -include $(DEPFILES)
 endif
-
@@ -0,0 +1,23 @@
+Additional Grant of Patent Rights
+
+“Software” means the rocksdb software distributed by Facebook, Inc.
+
+Facebook hereby grants you a perpetual, worldwide, royalty-free,
+non-exclusive, irrevocable (subject to the termination provision below)
+license under any rights in any patent claims owned by Facebook, to make,
+have made, use, sell, offer to sell, import, and otherwise transfer the
+Software. For avoidance of doubt, no license is granted under Facebook’s
+rights in any patent claims that are infringed by (i) modifications to the
+Software made by you or a third party, or (ii) the Software in combination
+with any software or other technology provided by you or a third party.
+
+The license granted hereunder will terminate, automatically and without
+notice, for anyone that makes any claim (including by filing any lawsuit,
+assertion or other action) alleging (a) direct, indirect, or contributory
+infringement or inducement to infringe any patent: (i) by Facebook or any
+of its subsidiaries or affiliates, whether or not such claim is related
+to the Software, (ii) by any party if such claim arises in whole or in
+part from any software, product or service of Facebook or any of its
+subsidiaries or affiliates, whether or not such claim is related to the
+Software, or (iii) by any party relating to the Software; or (b) that
+any right in any patent claim of Facebook is invalid or unenforceable.
@@ -1,6 +1,6 @@
 rocksdb: A persistent key-value store for flash storage
 Authors: * The Facebook Database Engineering Team
-         * Build on earlier work on leveldb by Sanjay Ghemawat 
+         * Build on earlier work on leveldb by Sanjay Ghemawat
           (sanjay@google.com) and Jeff Dean (jeff@google.com)

 This code is a library that forms the core building block for a fast
@@ -19,64 +19,64 @@ persistent key/value store.
 See doc/index.html for more explanation.
 See doc/impl.html for a brief overview of the implementation.

-The public interface is in include/*.h.  Callers should not include or
+The public interface is in include/*.  Callers should not include or
 rely on the details of any other header files in this package.  Those
 internal APIs may be changed without warning.

 Guide to header files:

-include/db.h
+include/rocksdb/db.h
    Main interface to the DB: Start here

-include/options.h
+include/rocksdb/options.h
    Control over the behavior of an entire database, and also
    control over the behavior of individual reads and writes.

-include/comparator.h
+include/rocksdb/comparator.h
    Abstraction for user-specified comparison function.  If you want
    just bytewise comparison of keys, you can use the default comparator,
    but clients can write their own comparator implementations if they
    want custom ordering (e.g. to handle different character
    encodings, etc.)

-include/iterator.h
+include/rocksdb/iterator.h
    Interface for iterating over data. You can get an iterator
    from a DB object.

-include/write_batch.h
+include/rocksdb/write_batch.h
    Interface for atomically applying multiple updates to a database.

-include/slice.h
+include/rocksdb/slice.h
    A simple module for maintaining a pointer and a length into some
    other byte array.

-include/status.h
+include/rocksdb/status.h
    Status is returned from many of the public interfaces and is used
    to report success and various kinds of errors.

-include/env.h
+include/rocksdb/env.h
    Abstraction of the OS environment.  A posix implementation of
    this interface is in util/env_posix.cc

-include/table_builder.h
+include/rocksdb/table_builder.h
    Lower-level modules that most clients probably won't use directly

-include/cache.h
+include/rocksdb/cache.h
    An API for the block cache.

-include/compaction_filter.h
+include/rocksdb/compaction_filter.h
    An API for a application filter invoked on every compaction.

-include/filter_policy.h
+include/rocksdb/filter_policy.h
    An API for configuring a bloom filter.

-include/memtablerep.h
+include/rocksdb/memtablerep.h
    An API for implementing a memtable.

-include/statistics.h
+include/rocksdb/statistics.h
    An API to retrieve various database statistics.

-include/transaction_log_iterator.h
+include/rocksdb/transaction_log.h
    An API to retrieve transaction logs from a database.


@@ -1,3 +1,3 @@
 * Detailed instructions on how to compile using fbcode and jemalloc

-* Latest release is 2.1.fb
+* Latest release is 2.5.fb
@@ -1,4 +0,0 @@
-This directory stores the tests that failed valgrind and the times associated
-with the failed runs.
-"make valgrind_check" can be invoked to call valgrind on the rocksdb tests and
-generate files in this directory
@@ -1,30 +0,0 @@
-#!/bin/sh
-#
-# Record the version of the source that we are compiling.
-# We keep a record of the git revision in util/version.cc. This source file
-# is then built as a regular source file as part of the compilation process.
-# One can run "strings executable_filename | grep _build_" to find the version of
-# the source that we used to build the executable file.
-#
-
-# create git version file
-VFILE=$(mktemp)
-trap "rm $VFILE" EXIT
-
-# check to see if git is in the path
-which git > /dev/null
-
-if [ "$?" = 0 ]; then
-  env -i git rev-parse HEAD | awk ' BEGIN {print "#include \"build_version.h\""} {print "const char * leveldb_build_git_sha = \"leveldb_build_git_sha:" $0"\";"} END {}' >  ${VFILE}
-else
-  echo "git not found"| awk ' BEGIN {print "#include \"build_version.h\""} {print "const char * leveldb_build_git_sha = \"leveldb_build_git_sha:git not found\";"} END {}' > ${VFILE}
-fi
-
-date | awk 'BEGIN {} {print "const char * leveldb_build_git_datetime = \"leveldb_build_git_datetime:"$0"\";"} END {} ' >> ${VFILE}
-echo "const char * leveldb_build_compile_date = __DATE__;" >> ${VFILE}
-echo "const char * leveldb_build_compile_time = __TIME__;" >> ${VFILE}
-
-OUTFILE=util/build_version.cc
-if [ ! -e $OUTFILE ] || ! cmp -s $VFILE $OUTFILE; then
-    cp $VFILE $OUTFILE
-fi
@@ -1,86 +0,0 @@
-#!/bin/bash -e
-function print_usage {
-  echo "Usage: $0 [build | release | bump_version version ]"
-}
-
-function check_env {
-  if [ -z $LEVELDB_HOME ] ; then
-    echo "Expect LEVELDB_HOME to be SET"
-    exit 1
-  fi
-  if [ -z $JAVA_HOME ] ; then
-    export JAVA_HOME=/usr/local/jdk-6u14-64/
-    echo "JAVA_HOME not set. Assuming JAVA_HOME=$JAVA_HOME"
-  fi
-  if [ -z $LEVELDBJNI_HOME ] ; then
-    export LEVELDBJNI_HOME=$LEVELDB_HOME/java/leveldbjni/
-    echo "LEVELDBJNI_HOME not set. Assuming LEVELDBJNI_HOME=$LEVELDBJNI_HOME"
-  fi
-  if [ -z $SNAPPY_HOME ] ; then
-    export SNAPPY_HOME="/home/dhruba/snappy-1.0.5"
-    echo "SNAPPY_HOME not set. Assuming SNAPPY_HOME=$SNAPPY_HOME"
-  fi
-  if [ -z $LEVELDB_PATCH ] ; then 
-    LEVELDB_PATCH=$LEVELDB_HOME/java/leveldbjni/db.h.patch
-    echo "LEVELDB_PATCH not set. Assuming LEVELDB_PATCH=$LEVELDB_PATCH"
-  fi
-}
-
-function build {
-  cd $LEVELDB_HOME
-  git apply $LEVELDB_PATCH
-  make clean libleveldb.a
-  cd $LEVELDB_HOME/java/leveldb/leveldb-api
-  mvn clean package
-  cd $LEVELDBJNI_HOME
-  mvn clean install -P linux64
-  cd $LEVELDB_HOME
-  git checkout $LEVELDB_HOME/include/leveldb/db.h
-}
-
-function release {
-  cd $LEVELDB_HOME
-  git apply $LEVELDB_PATCH
-  make clean libleveldb.a
-  cd $LEVELDB_HOME/java/leveldb/leveldb-api
-  mvn clean package
-  cd $LEVELDBJNI_HOME
-  mvn deploy -P linux64 -DskipTests
-  cd $LEVELDB_HOME
-  git checkout $LEVELDB_HOME/include/leveldb/db.h
-}
-
-CMD=$1
-if [ -z $CMD ]; then
-  print_usage
-  exit 1
-fi
-
-case "$CMD" in 
-  build) 
-    check_env
-    build
-    ;;
-  bump_version)
-    if [ -z $2 ] ; then
-      echo "bump_version requires a version.no parameter at the end"
-      exit 1
-    fi 
-    check_env
-    VERSION=$2
-    pushd $LEVELDBJNI_HOME
-    mvn versions:set -DnewVersion="$VERSION"
-    popd
-    echo "VERSION SET TO $VERSION"
-    ;;
-  release)
-    check_env
-    pushd $LEVELDBJNI_HOME
-    release
-    popd
-    ;;
-  *)
-    print_usage
-    exit 1
-    ;;
-esac
@@ -31,9 +31,9 @@ fi
 # Default to fbcode gcc on internal fb machines
 if [ -d /mnt/gvfs/third-party -a -z "$CXX" ]; then
    if [ -z "$USE_CLANG" ]; then
-        source ./fbcode.gcc471.sh
+        source $PWD/build_tools/fbcode.gcc471.sh
    else
-        source ./fbcode.clang31.sh
+        source $PWD/build_tools/fbcode.clang31.sh
    fi
 fi

@@ -65,7 +65,7 @@ PLATFORM_SHARED_CFLAGS="-fPIC"
 PLATFORM_SHARED_VERSIONED=true

 # generic port files (working on all platform by #ifdef) go directly in /port
-GENERIC_PORT_FILES=`find port -name '*.cc' | tr "\n" " "`
+GENERIC_PORT_FILES=`find $ROCKSDB_ROOT/port -name '*.cc' | tr "\n" " "`

 # On GCC, we pick libc's memcmp over GCC's memcmp via -fno-builtin-memcmp
 case "$TARGET_OS" in
@@ -78,11 +78,11 @@ case "$TARGET_OS" in
        ;;
    Linux)
        PLATFORM=OS_LINUX
-        COMMON_FLAGS="$COMMON_FLAGS -DOS_LINUX -fPIC"
+        COMMON_FLAGS="$COMMON_FLAGS -DOS_LINUX"
        if [ -z "$USE_CLANG" ]; then
            COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp"
        fi
-        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread"
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lpthread -lrt"
        # PORT_FILES=port/linux/linux_specific.cc
        ;;
    SunOS)
@@ -127,27 +127,19 @@ case "$TARGET_OS" in
        exit 1
 esac

-./build_detect_version
+$PWD/build_tools/build_detect_version

 # We want to make a list of all cc files within util, db, table, and helpers
 # except for the test and benchmark files. By default, find will output a list
 # of all files matching either rule, so we need to append -print to make the
 # prune take effect.
 DIRS="util db table utilities"
-if test "$USE_THRIFT"; then
-  DIRS="$DIRS thrift/server_utils.cpp thrift/gen-cpp "
-  THRIFTSERVER=leveldb_server
-fi
-
-if test "$USE_SCRIBE"; then
-  DIRS="$DIRS scribe "
-fi

 set -f # temporarily disable globbing so that our patterns arent expanded
 PRUNE_TEST="-name *test*.cc -prune"
 PRUNE_BENCH="-name *_bench.cc -prune"
-PORTABLE_FILES=`find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
-PORTABLE_CPP=`find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
+PORTABLE_FILES=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
+PORTABLE_CPP=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
 set +f # re-enable globbing

 # The sources consist of the portable files, plus the platform-specific port
@@ -183,6 +175,17 @@ EOF
        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS ${SNAPPY_LDFLAGS:-./snappy/libs/libsnappy.a}"
    fi

+
+    # Test whether gflags library is installed
+    # http://code.google.com/p/gflags/
+    $CXX $CFLAGS -x c++ - -o /dev/null 2>/dev/null  <<EOF
+      #include <gflags/gflags.h>
+      int main() {}
+EOF
+    if [ "$?" = 0 ]; then
+        COMMON_FLAGS="$COMMON_FLAGS -DGFLAGS"
+    fi
+
    # Test whether zlib library is installed
    $CXX $CFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null  <<EOF
      #include <zlib.h>
@@ -227,14 +230,6 @@ if test "$USE_HDFS"; then
  PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS $HDFS_LDFLAGS"
 fi

-# shall we build thrift server or scribe logger
-if test "$USE_THRIFT" ||  test "$USE_SCRIBE" ; then
-    THRIFT_CCFLAGS=" -I./thrift -I./thrift/gen-cpp -I./thrift/lib/cpp -I/usr/include -std=gnu++0x"
-    THRIFT_LDFLAGS=" -lexample -lserver -lthrift_base -ltransport -lthrift_exception -lutil -L./thrift/libs "
-    COMMON_FLAGS="$COMMON_FLAGS $THRIFT_CCFLAGS"
-    PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS $THRIFT_LDFLAGS"
-fi
-
 # if Intel SSE instruction set is supported, set USE_SSE=" -msse -msse4.2 "
 COMMON_FLAGS="$COMMON_FLAGS $USE_SSE"

@@ -254,5 +249,4 @@ echo "PLATFORM_SHARED_CFLAGS=$PLATFORM_SHARED_CFLAGS" >> $OUTPUT
 echo "PLATFORM_SHARED_EXT=$PLATFORM_SHARED_EXT" >> $OUTPUT
 echo "PLATFORM_SHARED_LDFLAGS=$PLATFORM_SHARED_LDFLAGS" >> $OUTPUT
 echo "PLATFORM_SHARED_VERSIONED=$PLATFORM_SHARED_VERSIONED" >> $OUTPUT
-echo "THRIFTSERVER=$THRIFTSERVER" >> $OUTPUT
 echo "EXEC_LDFLAGS=$EXEC_LDFLAGS" >> $OUTPUT
@@ -0,0 +1,42 @@
+#!/bin/sh
+#
+# Record the version of the source that we are compiling.
+# We keep a record of the git revision in util/version.cc. This source file
+# is then built as a regular source file as part of the compilation process.
+# One can run "strings executable_filename | grep _build_" to find the version of
+# the source that we used to build the executable file.
+#
+
+# create git version file
+VFILE=$ROCKSDB_ROOT/util/build_version.cc.tmp
+trap "rm $VFILE" EXIT
+
+# check to see if git is in the path
+which git > /dev/null
+
+if [ "$?" = 0 ]; then
+  env -i git rev-parse HEAD |
+  awk '
+  BEGIN {
+    print "#include \"build_version.h\"\n"
+  }
+  { print "const char* rocksdb_build_git_sha = \"rocksdb_build_git_sha:" $0"\";" }
+  ' >  ${VFILE}
+else
+  echo "git not found" |
+  awk '
+    BEGIN {
+      print "#include \"build_version.h\""
+    }
+    { print "const char* rocksdb_build_git_sha = \"rocksdb_build_git_sha:git not found\";" }
+    ' > ${VFILE}
+fi
+
+echo "const char* rocksdb_build_git_datetime = \"rocksdb_build_git_datetime:$(date)\";" >> ${VFILE}
+echo "const char* rocksdb_build_compile_date = __DATE__;" >> ${VFILE}
+echo "const char* rocksdb_build_compile_time = __TIME__;" >> ${VFILE}
+
+OUTFILE=$ROCKSDB_ROOT/util/build_version.cc
+if [ ! -e $OUTFILE ] || ! cmp -s $VFILE $OUTFILE; then
+    cp $VFILE $OUTFILE
+fi
@@ -4,30 +4,29 @@
 # fbcode settings.  It uses the latest g++ compiler and also
 # uses jemalloc

-TOOLCHAIN_REV=f365dbeae46a30414a2874a6f45e73e10f1caf7d
+TOOLCHAIN_REV=fbe3b095a4cc4a3713730050d182b7b4a80c342f
 TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos5.2-native"
 TOOLCHAIN_LIB_BASE="/mnt/gvfs/third-party/$TOOLCHAIN_REV/gcc-4.7.1-glibc-2.14.1"
-TOOL_JEMALLOC=jemalloc-3.0.0/2f45f3a
+TOOL_JEMALLOC=jemalloc-3.3.1/9202ce3
 GLIBC_RUNTIME_PATH=/usr/local/fbcode/gcc-4.7.1-glibc-2.14.1

 # location of snappy headers and libraries
 SNAPPY_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/include"
 SNAPPY_LIBS=" $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/lib/libsnappy.a"

-# location of boost headers and libraries
-THRIFT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/bef9365/include -std=gnu++0x"
-THRIFT_INCLUDE+=" -I./thrift -I./thrift/gen-cpp -I./thrift/lib/cpp"
-THRIFT_LIBS=" -L $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/bef9365/lib"
-
 # location of libevent
 LIBEVENT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/include"
 LIBEVENT_LIBS=" -L $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/lib"

+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/include"
+GFLAGS_LIBS=" $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/lib/libgflags.a"
+
 # use Intel SSE support for checksum calculations
 export USE_SSE=" -msse -msse4.2 "

 CC="$TOOLCHAIN_EXECUTABLES/clang/clang-3.1/6ca8a59/bin/clang $CLANG_INCLUDES"
-CXX="$TOOLCHAIN_EXECUTABLES/clang/clang-3.1/6ca8a59/bin/clang++ $CLANG_INCLUDES $JINCLUDE $SNAPPY_INCLUDE $THRIFT_INCLUDE $LIBEVENT_INCLUDE"
+CXX="$TOOLCHAIN_EXECUTABLES/clang/clang-3.1/6ca8a59/bin/clang++ $CLANG_INCLUDES $JINCLUDE $SNAPPY_INCLUDE $LIBEVENT_INCLUDE $GFLAGS_INCLUDE"
 AR=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ar
 RANLIB=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ranlib

@@ -37,8 +36,8 @@ CXXFLAGS="$CFLAGS -nostdinc++ -std=gnu++0x"
 CFLAGS+=" -I $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/include -DHAVE_JEMALLOC"

 EXEC_LDFLAGS=" -Wl,--whole-archive $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/lib/libjemalloc.a"
-EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/91ddd43/lib/libunwind.a"
-EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $THRIFT_LIBS $LIBEVENT_LIBS"
+EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/350336c/lib/libunwind.a"
+EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $LIBEVENT_LIBS $GFLAGS_LIBS"
 EXEC_LDFLAGS+=" -Wl,--dynamic-linker,$GLIBC_RUNTIME_PATH/lib/ld-linux-x86-64.so.2"
 EXEC_LDFLAGS+=" -B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin"

@@ -4,10 +4,10 @@
 # fbcode settings.  It uses the latest g++ compiler and also
 # uses jemalloc

-TOOLCHAIN_REV=83eb773e262fa705eaebbf3de40db71d53fabf2e
+TOOLCHAIN_REV=fbe3b095a4cc4a3713730050d182b7b4a80c342f
 TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos5.2-native"
 TOOLCHAIN_LIB_BASE="/mnt/gvfs/third-party/$TOOLCHAIN_REV/gcc-4.7.1-glibc-2.14.1"
-TOOL_JEMALLOC=jemalloc-3.3.1/2f45f3a
+TOOL_JEMALLOC=jemalloc-3.3.1/9202ce3

 # location of libhdfs libraries
 if test "$USE_HDFS"; then
@@ -15,7 +15,7 @@ if test "$USE_HDFS"; then
  JINCLUDE="-I$JAVA_HOME/include -I$JAVA_HOME/include/linux"
  GLIBC_RUNTIME_PATH="/usr/local/fbcode/gcc-4.7.1-glibc-2.14.1"
  HDFSLIB=" -Wl,--no-whole-archive hdfs/libhdfs.a -L$JAVA_HOME/jre/lib/amd64 "
-  HDFSLIB+=" -L$JAVA_HOME/jre/lib/amd64/server -L$GLIBC_RUNTIME_PATH/lib " 
+  HDFSLIB+=" -L$JAVA_HOME/jre/lib/amd64/server -L$GLIBC_RUNTIME_PATH/lib "
  HDFSLIB+=" -ldl -lverify -ljava -ljvm "
 fi

@@ -27,20 +27,19 @@ SNAPPY_LIBS=" $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/lib/libsnappy.a"
 ZLIB_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/91ddd43/include"
 ZLIB_LIBS=" $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/91ddd43/lib/libz.a"

-# location of boost headers and libraries
-THRIFT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/2a0840d/include"
-THRIFT_INCLUDE+=" -I./thrift -I./thrift/gen-cpp -I./thrift/lib/cpp"
-THRIFT_LIBS=" -L $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/2a0840d/lib"
-
 # location of libevent
 LIBEVENT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/include"
 LIBEVENT_LIBS=" -L $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/lib"

+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/include"
+GFLAGS_LIBS=" $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/lib/libgflags.a"
+
 # use Intel SSE support for checksum calculations
 export USE_SSE=" -msse -msse4.2 "

 CC="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1-glibc-2.14.1/bin/gcc"
-CXX="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1-glibc-2.14.1/bin/g++ $JINCLUDE $SNAPPY_INCLUDE $ZLIB_INCLUDE $THRIFT_INCLUDE $LIBEVENT_INCLUDE"
+CXX="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1-glibc-2.14.1/bin/g++ $JINCLUDE $SNAPPY_INCLUDE $ZLIB_INCLUDE $LIBEVENT_INCLUDE $GFLAGS_INCLUDE"
 AR=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ar
 RANLIB=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ranlib

@@ -48,8 +47,8 @@ CFLAGS="-B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/bin/gold -m64 -mtune=g
 CFLAGS+=" -I $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/include -DHAVE_JEMALLOC"

 EXEC_LDFLAGS=" -Wl,--whole-archive $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/lib/libjemalloc.a"
-EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/91ddd43/lib/libunwind.a"
-EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $ZLIB_LIBS $THRIFT_LIBS $LIBEVENT_LIBS"
+EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/350336c/lib/libunwind.a"
+EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $ZLIB_LIBS $LIBEVENT_LIBS $GFLAGS_LIBS"

 PLATFORM_LDFLAGS="-L$TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/lib -L$TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/lib"

@@ -14,8 +14,8 @@ fi
 # On the production build servers, set data and stat
 # files/directories not in /tmp or else the tempdir cleaning
 # scripts will make you very unhappy.
-DATA_DIR=${DATA_DIR:-$(mktemp --tmpdir -d leveldb_XXXX)}
-STAT_FILE=${STAT_FILE:-$(mktemp --tmpdir -u leveldb_test_stats_XXXX)}
+DATA_DIR=${DATA_DIR:-$(mktemp -t -d rocksdb_XXXX)}
+STAT_FILE=${STAT_FILE:-$(mktemp -t -u rocksdb_test_stats_XXXX)}

 function cleanup {
  rm -rf $DATA_DIR
@@ -34,7 +34,8 @@ function send_to_ods {
    echo >&2 "ERROR: Key $key doesn't have a value."
    return
  fi
-  curl -s "https://www.intern.facebook.com/intern/agent/ods_set.php?entity=rocksdb_build&key=$key&value=$value"
+  curl -s "https://www.intern.facebook.com/intern/agent/ods_set.php?entity=rocksdb_build&key=$key&value=$value" \
+    --connect-timeout 60
 }

 make clean
@@ -2,7 +2,7 @@
 #A shell script for Jenknis to run valgrind on rocksdb tests
 #Returns 0 on success when there are no failed tests 

-VALGRIND_DIR=VALGRIND_LOGS
+VALGRIND_DIR=build_tools/VALGRIND_LOGS
 make clean
 make -j$(nproc) valgrind_check
 NUM_FAILED_TESTS=$((`wc -l $VALGRIND_DIR/valgrind_failed_tests | awk '{print $1}'` - 1))
@@ -0,0 +1,73 @@
+#!/bin/bash
+
+# Exit on error.
+set -e
+
+if [ -n "$USE_CLANG" ]; then
+  echo "Error: Coverage test is supported only for gcc."
+  exit 1
+fi
+
+ROOT=".."
+# Fetch right version of gcov
+if [ -d /mnt/gvfs/third-party -a -z "$CXX" ]; then
+  source $ROOT/build_tools/fbcode.gcc471.sh
+  GCOV=$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1/cc6c9dc/bin/gcov
+else
+  GCOV=$(which gcov)
+fi
+
+COVERAGE_DIR="$PWD/COVERAGE_REPORT"
+mkdir -p $COVERAGE_DIR
+
+# Find all gcno files to generate the coverage report
+
+GCNO_FILES=`find $ROOT -name "*.gcno"`
+$GCOV --preserve-paths --relative-only --no-output $GCNO_FILES 2>/dev/null |
+  # Parse the raw gcov report to more human readable form.
+  python $ROOT/coverage/parse_gcov_output.py |
+  # Write the output to both stdout and report file.
+  tee $COVERAGE_DIR/coverage_report_all.txt &&
+echo -e "Generated coverage report for all files: $COVERAGE_DIR/coverage_report_all.txt\n"
+
+# TODO: we also need to get the files of the latest commits.
+# Get the most recently committed files.
+LATEST_FILES=`
+  git show --pretty="format:" --name-only HEAD |
+  grep -v "^$" |
+  paste -s -d,`
+RECENT_REPORT=$COVERAGE_DIR/coverage_report_recent.txt
+
+echo -e "Recently updated files: $LATEST_FILES\n" > $RECENT_REPORT
+$GCOV --preserve-paths --relative-only --no-output $GCNO_FILES 2>/dev/null |
+  python $ROOT/coverage/parse_gcov_output.py -interested-files $LATEST_FILES |
+  tee -a $RECENT_REPORT &&
+echo -e "Generated coverage report for recently updated files: $RECENT_REPORT\n"
+
+# Generate the html report. If we cannot find lcov in this machine, we'll simply
+# skip this step.
+echo "Generating the html coverage report..."
+
+LCOV=$(which lcov || true 2>/dev/null)
+if [ -z $LCOV ]
+then
+  echo "Skip: Cannot find lcov to generate the html report."
+  exit 0
+fi
+
+LCOV_VERSION=$(lcov -v | grep 1.1 || true)
+if [ $LCOV_VERSION ]
+then
+  echo "Not supported lcov version. Expect lcov 1.1."
+  exit 0
+fi
+
+(cd $ROOT; lcov --no-external \
+     --capture  \
+     --directory $PWD \
+     --gcov-tool $GCOV \
+     --output-file $COVERAGE_DIR/coverage.info)
+
+genhtml $COVERAGE_DIR/coverage.info -o $COVERAGE_DIR
+
+echo "HTML Coverage report is generated in $COVERAGE_DIR"
@@ -0,0 +1,118 @@
+import optparse
+import re
+import sys
+
+from optparse import OptionParser
+
+# the gcov report follows certain pattern. Each file will have two lines
+# of report, from which we can extract the file name, total lines and coverage
+# percentage.
+def parse_gcov_report(gcov_input):
+    per_file_coverage = {}
+    total_coverage = None
+
+    for line in sys.stdin:
+        line = line.strip()
+
+        # --First line of the coverage report (with file name in it)?
+        match_obj = re.match("^File '(.*)'$", line)
+        if match_obj:
+            # fetch the file name from the first line of the report.
+            current_file = match_obj.group(1)
+            continue
+
+        # -- Second line of the file report (with coverage percentage)
+        match_obj = re.match("^Lines executed:(.*)% of (.*)", line)
+
+        if match_obj:
+            coverage = float(match_obj.group(1))
+            lines = int(match_obj.group(2))
+
+            if current_file is not None:
+                per_file_coverage[current_file] = (coverage, lines)
+                current_file = None
+            else:
+                # If current_file is not set, we reach the last line of report,
+                # which contains the summarized coverage percentage.
+                total_coverage = (coverage, lines)
+            continue
+
+        # If the line's pattern doesn't fall into the above categories. We
+        # can simply ignore them since they're either empty line or doesn't
+        # find executable lines of the given file.
+        current_file = None
+
+    return per_file_coverage, total_coverage
+
+def get_option_parser():
+    usage = "Parse the gcov output and generate more human-readable code " +\
+            "coverage report."
+    parser = OptionParser(usage)
+
+    parser.add_option(
+        "--interested-files", "-i",
+        dest="filenames",
+        help="Comma separated files names. if specified, we will display " +
+             "the coverage report only for interested source files. " +
+             "Otherwise we will display the coverage report for all " +
+             "source files."
+    )
+    return parser
+
+def display_file_coverage(per_file_coverage, total_coverage):
+    # To print out auto-adjustable column, we need to know the longest
+    # length of file names.
+    max_file_name_length = max(
+        len(fname) for fname in per_file_coverage.keys()
+    )
+
+    # -- Print header
+    # size of separator is determined by 3 column sizes:
+    # file name, coverage percentage and lines.
+    header_template = \
+        "%" + str(max_file_name_length) + "s\t%s\t%s"
+    separator = "-" * (max_file_name_length + 10 + 20)
+    print header_template % ("Filename", "Coverage", "Lines")
+    print separator
+
+    # -- Print body
+    # template for printing coverage report for each file.
+    record_template = "%" + str(max_file_name_length) + "s\t%5.2f%%\t%10d"
+
+    for fname, coverage_info in per_file_coverage.items():
+        coverage, lines = coverage_info
+        print record_template % (fname, coverage, lines)
+
+    # -- Print footer
+    if total_coverage:
+        print separator
+        print record_template % ("Total", total_coverage[0], total_coverage[1])
+
+def report_coverage():
+    parser = get_option_parser()
+    (options, args) = parser.parse_args()
+
+    interested_files = set()
+    if options.filenames is not None:
+        interested_files = set(f.strip() for f in options.filenames.split(','))
+
+    # To make things simple, right now we only read gcov report from the input
+    per_file_coverage, total_coverage = parse_gcov_report(sys.stdin)
+
+    # Check if we need to display coverage info for interested files.
+    if len(interested_files):
+        per_file_coverage = dict(
+            (fname, per_file_coverage[fname]) for fname in interested_files
+            if fname in per_file_coverage
+        )
+        # If we only interested in several files, it makes no sense to report
+        # the total_coverage
+        total_coverage = None
+
+    if not len(per_file_coverage):
+        print >> sys.stderr, "Cannot find coverage info for the given files."
+        return
+    display_file_coverage(per_file_coverage, total_coverage)
+
+if __name__ == "__main__":
+    report_coverage()
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -9,12 +14,23 @@
 #include "db/merge_helper.h"
 #include "db/table_cache.h"
 #include "db/version_edit.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
-#include "leveldb/iterator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/table.h"
+#include "rocksdb/env.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+#include "table/block_based_table_builder.h"
 #include "util/stop_watch.h"

-namespace leveldb {
+namespace rocksdb {
+
+class TableFactory;
+
+TableBuilder* GetTableBuilder(const Options& options, WritableFile* file,
+                              CompressionType compression_type) {
+  return options.table_factory->GetTableBuilder(options, file,
+                                                compression_type);
+}

 Status BuildTable(const std::string& dbname,
                  Env* env,
@@ -25,9 +41,11 @@ Status BuildTable(const std::string& dbname,
                  FileMetaData* meta,
                  const Comparator* user_comparator,
                  const SequenceNumber newest_snapshot,
-                  const SequenceNumber earliest_seqno_in_memtable) {
+                  const SequenceNumber earliest_seqno_in_memtable,
+                  const bool enable_compression) {
  Status s;
  meta->file_size = 0;
+  meta->smallest_seqno = meta->largest_seqno = 0;
  iter->SeekToFirst();

  // If the sequence number of the smallest entry in the memtable is
@@ -45,12 +63,17 @@ Status BuildTable(const std::string& dbname,
    if (!s.ok()) {
      return s;
    }
-    TableBuilder* builder = new TableBuilder(options, file.get(), 0);
+
+    TableBuilder* builder = GetTableBuilder(options, file.get(),
+                                            options.compression);

    // the first key is the smallest key
-    meta->smallest.DecodeFrom(iter->key());
+    Slice key = iter->key();
+    meta->smallest.DecodeFrom(key);
+    meta->smallest_seqno = GetInternalKeySeqno(key);
+    meta->largest_seqno = meta->smallest_seqno;

-    MergeHelper merge(user_comparator, options.merge_operator,
+    MergeHelper merge(user_comparator, options.merge_operator.get(),
                      options.info_log.get(),
                      true /* internal key corruption is not ok */);

@@ -135,12 +158,18 @@ Status BuildTable(const std::string& dbname,

      // The last key is the largest key
      meta->largest.DecodeFrom(Slice(prev_key));
+      SequenceNumber seqno = GetInternalKeySeqno(Slice(prev_key));
+      meta->smallest_seqno = std::min(meta->smallest_seqno, seqno);
+      meta->largest_seqno = std::max(meta->largest_seqno, seqno);

    } else {
      for (; iter->Valid(); iter->Next()) {
        Slice key = iter->key();
        meta->largest.DecodeFrom(key);
        builder->Add(key, iter->value());
+        SequenceNumber seqno = GetInternalKeySeqno(key);
+        meta->smallest_seqno = std::min(meta->smallest_seqno, seqno);
+        meta->largest_seqno = std::max(meta->largest_seqno, seqno);
      }
    }

@@ -194,4 +223,4 @@ Status BuildTable(const std::string& dbname,
  return s;
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,15 +1,17 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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 "rocksdb/comparator.h"
+#include "rocksdb/status.h"
+#include "rocksdb/types.h"
+#include "rocksdb/options.h"

-#ifndef STORAGE_LEVELDB_DB_BUILDER_H_
-#define STORAGE_LEVELDB_DB_BUILDER_H_
-
-#include "leveldb/comparator.h"
-#include "leveldb/status.h"
-#include "leveldb/types.h"
-
-namespace leveldb {
+namespace rocksdb {

 struct Options;
 struct FileMetaData;
@@ -19,6 +21,12 @@ class EnvOptions;
 class Iterator;
 class TableCache;
 class VersionEdit;
+class TableBuilder;
+class WritableFile;
+
+
+extern TableBuilder* GetTableBuilder(const Options& options, WritableFile* file,
+                                     CompressionType compression_type);

 // Build a Table file from the contents of *iter.  The generated file
 // will be named according to meta->number.  On success, the rest of
@@ -34,8 +42,7 @@ extern Status BuildTable(const std::string& dbname,
                         FileMetaData* meta,
                         const Comparator* user_comparator,
                         const SequenceNumber newest_snapshot,
-                         const SequenceNumber earliest_seqno_in_memtable);
+                         const SequenceNumber earliest_seqno_in_memtable,
+                         const bool enable_compression);

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_BUILDER_H_
+}  // namespace rocksdb
@@ -1,43 +1,48 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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 "leveldb/c.h"
+#include "rocksdb/c.h"

 #include <stdlib.h>
 #include <unistd.h>
-#include "leveldb/cache.h"
-#include "leveldb/comparator.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
-#include "leveldb/filter_policy.h"
-#include "leveldb/iterator.h"
-#include "leveldb/options.h"
-#include "leveldb/status.h"
-#include "leveldb/write_batch.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/filter_policy.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+#include "rocksdb/status.h"
+#include "rocksdb/write_batch.h"

-using leveldb::Cache;
-using leveldb::Comparator;
-using leveldb::CompressionType;
-using leveldb::DB;
-using leveldb::Env;
-using leveldb::FileLock;
-using leveldb::FilterPolicy;
-using leveldb::Iterator;
-using leveldb::Logger;
-using leveldb::NewBloomFilterPolicy;
-using leveldb::NewLRUCache;
-using leveldb::Options;
-using leveldb::RandomAccessFile;
-using leveldb::Range;
-using leveldb::ReadOptions;
-using leveldb::SequentialFile;
-using leveldb::Slice;
-using leveldb::Snapshot;
-using leveldb::Status;
-using leveldb::WritableFile;
-using leveldb::WriteBatch;
-using leveldb::WriteOptions;
+using rocksdb::Cache;
+using rocksdb::Comparator;
+using rocksdb::CompressionType;
+using rocksdb::DB;
+using rocksdb::Env;
+using rocksdb::FileLock;
+using rocksdb::FilterPolicy;
+using rocksdb::Iterator;
+using rocksdb::Logger;
+using rocksdb::NewBloomFilterPolicy;
+using rocksdb::NewLRUCache;
+using rocksdb::Options;
+using rocksdb::RandomAccessFile;
+using rocksdb::Range;
+using rocksdb::ReadOptions;
+using rocksdb::SequentialFile;
+using rocksdb::Slice;
+using rocksdb::Snapshot;
+using rocksdb::Status;
+using rocksdb::WritableFile;
+using rocksdb::WriteBatch;
+using rocksdb::WriteOptions;

 using std::shared_ptr;

@@ -549,6 +554,11 @@ void leveldb_options_set_WAL_ttl_seconds(leveldb_options_t* opt, uint64_t ttl) {
  opt->rep.WAL_ttl_seconds = ttl;
 }

+void leveldb_options_set_WAL_size_limit_MB(
+    leveldb_options_t* opt, uint64_t limit) {
+  opt->rep.WAL_size_limit_MB = limit;
+}
+
 leveldb_comparator_t* leveldb_comparator_create(
    void* state,
    void (*destructor)(void*),
@@ -2,7 +2,7 @@
   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 "leveldb/c.h"
+#include "rocksdb/c.h"

 #include <stddef.h>
 #include <stdio.h>
@@ -296,7 +296,7 @@ int main(int argc, char** argv) {
  {
    char* prop = leveldb_property_value(db, "nosuchprop");
    CheckCondition(prop == NULL);
-    prop = leveldb_property_value(db, "leveldb.stats");
+    prop = leveldb_property_value(db, "rocksdb.stats");
    CheckCondition(prop != NULL);
    Free(&prop);
  }
@@ -1,26 +1,31 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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 "leveldb/db.h"
+#include "rocksdb/db.h"

 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include "leveldb/cache.h"
-#include "leveldb/env.h"
-#include "leveldb/write_batch.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/env.h"
+#include "rocksdb/table.h"
+#include "rocksdb/write_batch.h"
 #include "db/db_impl.h"
 #include "db/filename.h"
 #include "db/log_format.h"
 #include "db/version_set.h"
-#include "table/table.h"
 #include "util/logging.h"
 #include "util/testharness.h"
 #include "util/testutil.h"

-namespace leveldb {
+namespace rocksdb {

 static const int kValueSize = 1000;

@@ -68,7 +73,7 @@ class CorruptionTest {
  void RepairDB() {
    delete db_;
    db_ = nullptr;
-    ASSERT_OK(::leveldb::RepairDB(dbname_, options_));
+    ASSERT_OK(::rocksdb::RepairDB(dbname_, options_));
  }

  void Build(int n) {
@@ -216,10 +221,15 @@ TEST(CorruptionTest, NewFileErrorDuringWrite) {
  const int num = 3 + (Options().write_buffer_size / kValueSize);
  std::string value_storage;
  Status s;
-  for (int i = 0; s.ok() && i < num; i++) {
+  bool failed = false;
+  for (int i = 0; i < num; i++) {
    WriteBatch batch;
    batch.Put("a", Value(100, &value_storage));
    s = db_->Write(WriteOptions(), &batch);
+    if (!s.ok()) {
+      failed = true;
+    }
+    ASSERT_TRUE(!failed || !s.ok());
  }
  ASSERT_TRUE(!s.ok());
  ASSERT_GE(env_.num_writable_file_errors_, 1);
@@ -230,7 +240,7 @@ TEST(CorruptionTest, NewFileErrorDuringWrite) {
 TEST(CorruptionTest, TableFile) {
  Build(100);
  DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
  dbi->TEST_CompactRange(0, nullptr, nullptr);
  dbi->TEST_CompactRange(1, nullptr, nullptr);

@@ -241,7 +251,7 @@ TEST(CorruptionTest, TableFile) {
 TEST(CorruptionTest, TableFileIndexData) {
  Build(10000);  // Enough to build multiple Tables
  DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();

  Corrupt(kTableFile, -2000, 500);
  Reopen();
@@ -279,7 +289,7 @@ TEST(CorruptionTest, SequenceNumberRecovery) {
 TEST(CorruptionTest, CorruptedDescriptor) {
  ASSERT_OK(db_->Put(WriteOptions(), "foo", "hello"));
  DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
  dbi->TEST_CompactRange(0, nullptr, nullptr);

  Corrupt(kDescriptorFile, 0, 1000);
@@ -296,9 +306,9 @@ TEST(CorruptionTest, CorruptedDescriptor) {
 TEST(CorruptionTest, CompactionInputError) {
  Build(10);
  DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
  const int last = dbi->MaxMemCompactionLevel();
-  ASSERT_EQ(1, Property("leveldb.num-files-at-level" + NumberToString(last)));
+  ASSERT_EQ(1, Property("rocksdb.num-files-at-level" + NumberToString(last)));

  Corrupt(kTableFile, 100, 1);
  Check(9, 9);
@@ -319,12 +329,13 @@ TEST(CorruptionTest, CompactionInputErrorParanoid) {
  for (int level = 1; level < dbi->NumberLevels(); level++) {
    dbi->Put(WriteOptions(), "", "begin");
    dbi->Put(WriteOptions(), "~", "end");
-    dbi->TEST_CompactMemTable();
+    dbi->TEST_FlushMemTable();
  }

  Build(10);
-  dbi->TEST_CompactMemTable();
-  ASSERT_EQ(1, Property("leveldb.num-files-at-level0"));
+  dbi->TEST_FlushMemTable();
+  dbi->TEST_WaitForCompact();
+  ASSERT_EQ(1, Property("rocksdb.num-files-at-level0"));

  Corrupt(kTableFile, 100, 1);
  Check(9, 9);
@@ -332,8 +343,14 @@ TEST(CorruptionTest, CompactionInputErrorParanoid) {
  // Write must eventually fail because of corrupted table
  Status s;
  std::string tmp1, tmp2;
+  bool failed = false;
  for (int i = 0; i < 10000 && s.ok(); i++) {
    s = db_->Put(WriteOptions(), Key(i, &tmp1), Value(i, &tmp2));
+    if (!s.ok()) {
+      failed = true;
+    }
+    // if one write failed, every subsequent write must fail, too
+    ASSERT_TRUE(!failed || !s.ok()) << "write did not fail in a corrupted db";
  }
  ASSERT_TRUE(!s.ok()) << "write did not fail in corrupted paranoid db";
 }
@@ -341,7 +358,7 @@ TEST(CorruptionTest, CompactionInputErrorParanoid) {
 TEST(CorruptionTest, UnrelatedKeys) {
  Build(10);
  DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
  Corrupt(kTableFile, 100, 1);

  std::string tmp1, tmp2;
@@ -349,13 +366,13 @@ TEST(CorruptionTest, UnrelatedKeys) {
  std::string v;
  ASSERT_OK(db_->Get(ReadOptions(), Key(1000, &tmp1), &v));
  ASSERT_EQ(Value(1000, &tmp2).ToString(), v);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
  ASSERT_OK(db_->Get(ReadOptions(), Key(1000, &tmp1), &v));
  ASSERT_EQ(Value(1000, &tmp2).ToString(), v);
 }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,18 +1,24 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

-#include "db/db_impl.h"
-#include "db/filename.h"
+#include <algorithm>
 #include <string>
 #include <stdint.h>
+#include "db/db_impl.h"
+#include "db/filename.h"
 #include "db/version_set.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
 #include "port/port.h"
 #include "util/mutexlock.h"

-namespace leveldb {
+namespace rocksdb {

 Status DBImpl::DisableFileDeletions() {
  MutexLock l(&mutex_);
@@ -29,16 +35,19 @@ Status DBImpl::EnableFileDeletions() {
 }

 Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
-                            uint64_t* manifest_file_size) {
+                            uint64_t* manifest_file_size,
+                            bool flush_memtable) {

  *manifest_file_size = 0;

-  // flush all dirty data to disk.
-  Status status =  Flush(FlushOptions());
-  if (!status.ok()) {
-    Log(options_.info_log, "Cannot Flush data %s\n",
-        status.ToString().c_str());
-    return status;
+  if (flush_memtable) {
+    // flush all dirty data to disk.
+    Status status =  Flush(FlushOptions());
+    if (!status.ok()) {
+      Log(options_.info_log, "Cannot Flush data %s\n",
+          status.ToString().c_str());
+      return status;
+    }
  }

  MutexLock l(&mutex_);
@@ -47,18 +56,17 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
  std::set<uint64_t> live;
  versions_->AddLiveFilesCurrentVersion(&live);

-  ret.resize(live.size() + 2); //*.sst + CURRENT + MANIFEST
+  ret.clear();
+  ret.reserve(live.size() + 2); //*.sst + CURRENT + MANIFEST

  // create names of the live files. The names are not absolute
  // paths, instead they are relative to dbname_;
-  std::set<uint64_t>::iterator it = live.begin();
-  for (unsigned int i = 0; i < live.size(); i++, it++) {
-    ret[i] = TableFileName("", *it);
+  for (auto live_file : live) {
+    ret.push_back(TableFileName("", live_file));
  }

-  ret[live.size()] = CurrentFileName("");
-  ret[live.size()+1] = DescriptorFileName("",
-                                          versions_->ManifestFileNumber());
+  ret.push_back(CurrentFileName(""));
+  ret.push_back(DescriptorFileName("", versions_->ManifestFileNumber()));

  // find length of manifest file while holding the mutex lock
  *manifest_file_size = versions_->ManifestFileSize();
@@ -66,4 +74,21 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
  return Status::OK();
 }

+Status DBImpl::GetSortedWalFiles(VectorLogPtr& files) {
+  // First get sorted files in archive dir, then append sorted files from main
+  // dir to maintain sorted order
+
+  // list wal files in archive dir.
+  Status s;
+  std::string archivedir = ArchivalDirectory(options_.wal_dir);
+  if (env_->FileExists(archivedir)) {
+    s = AppendSortedWalsOfType(archivedir, files, kArchivedLogFile);
+    if (!s.ok()) {
+      return s;
+    }
+  }
+  // list wal files in main db dir.
+  return AppendSortedWalsOfType(options_.wal_dir, files, kAliveLogFile);
+}
+
 }
@@ -1,30 +1,28 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
-
-#ifndef STORAGE_LEVELDB_DB_DB_IMPL_H_
-#define STORAGE_LEVELDB_DB_DB_IMPL_H_
-
+#pragma once
 #include <atomic>
 #include <deque>
 #include <set>
 #include <vector>
 #include "db/dbformat.h"
-#include "db/log_file.h"
 #include "db/log_writer.h"
 #include "db/snapshot.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/memtablerep.h"
+#include "rocksdb/transaction_log.h"
 #include "port/port.h"
 #include "util/stats_logger.h"
 #include "memtablelist.h"
-#include "leveldb/memtablerep.h"

-#ifdef USE_SCRIBE
-#include "scribe/scribe_logger.h"
-#endif
-
-namespace leveldb {
+namespace rocksdb {

 class MemTable;
 class TableCache;
@@ -64,7 +62,7 @@ class DBImpl : public DB {
  virtual bool GetProperty(const Slice& property, std::string* value);
  virtual void GetApproximateSizes(const Range* range, int n, uint64_t* sizes);
  virtual void CompactRange(const Slice* begin, const Slice* end,
-                            bool reduce_level = false);
+                            bool reduce_level = false, int target_level = -1);
  virtual int NumberLevels();
  virtual int MaxMemCompactionLevel();
  virtual int Level0StopWriteTrigger();
@@ -72,21 +70,27 @@ class DBImpl : public DB {
  virtual Status DisableFileDeletions();
  virtual Status EnableFileDeletions();
  virtual Status GetLiveFiles(std::vector<std::string>&,
-                              uint64_t* manifest_file_size);
-  virtual SequenceNumber GetLatestSequenceNumber();
+                              uint64_t* manifest_file_size,
+                              bool flush_memtable = true);
+  virtual Status GetSortedWalFiles(VectorLogPtr& files);
+  virtual SequenceNumber GetLatestSequenceNumber() const;
  virtual Status GetUpdatesSince(SequenceNumber seq_number,
                                 unique_ptr<TransactionLogIterator>* iter);
+  virtual Status DeleteFile(std::string name);
+
+  virtual void GetLiveFilesMetaData(
+    std::vector<LiveFileMetaData> *metadata);

  // Extra methods (for testing) that are not in the public DB interface

  // Compact any files in the named level that overlap [*begin, *end]
  void TEST_CompactRange(int level, const Slice* begin, const Slice* end);

-  // Force current memtable contents to be compacted.
-  Status TEST_CompactMemTable();
+  // Force current memtable contents to be flushed.
+  Status TEST_FlushMemTable();

  // Wait for memtable compaction
-  Status TEST_WaitForCompactMemTable();
+  Status TEST_WaitForFlushMemTable();

  // Wait for any compaction
  Status TEST_WaitForCompact();
@@ -109,6 +113,14 @@ class DBImpl : public DB {
  // Trigger's a background call for testing.
  void TEST_PurgeObsoleteteWAL();

+  // get total level0 file size. Only for testing.
+  uint64_t TEST_GetLevel0TotalSize() { return versions_->NumLevelBytes(0);}
+
+  void TEST_SetDefaultTimeToCheck(uint64_t default_interval_to_delete_obsolete_WAL)
+  {
+    default_interval_to_delete_obsolete_WAL_ = default_interval_to_delete_obsolete_WAL;
+  }
+
 protected:
  Env* const env_;
  const std::string dbname_;
@@ -148,9 +160,9 @@ class DBImpl : public DB {
  // Delete any unneeded files and stale in-memory entries.
  void DeleteObsoleteFiles();

-  // Compact the in-memory write buffer to disk.  Switches to a new
+  // Flush the in-memory write buffer to storage.  Switches to a new
  // log-file/memtable and writes a new descriptor iff successful.
-  Status CompactMemTable(bool* madeProgress = nullptr);
+  Status FlushMemTableToOutputFile(bool* madeProgress = nullptr);

  Status RecoverLogFile(uint64_t log_number,
                        VersionEdit* edit,
@@ -173,18 +185,21 @@ class DBImpl : public DB {
  // Force current memtable contents to be flushed.
  Status FlushMemTable(const FlushOptions& options);

-  // Wait for memtable compaction
-  Status WaitForCompactMemTable();
+  // Wait for memtable flushed
+  Status WaitForFlushMemTable();

  void MaybeScheduleLogDBDeployStats();
  static void BGLogDBDeployStats(void* db);
  void LogDBDeployStats();

-  void MaybeScheduleCompaction();
-  static void BGWork(void* db);
-  void BackgroundCall();
-  Status BackgroundCompaction(bool* madeProgress, DeletionState& deletion_state);
-  void CleanupCompaction(CompactionState* compact);
+  void MaybeScheduleFlushOrCompaction();
+  static void BGWorkCompaction(void* db);
+  static void BGWorkFlush(void* db);
+  void BackgroundCallCompaction();
+  void BackgroundCallFlush();
+  Status BackgroundCompaction(bool* madeProgress,DeletionState& deletion_state);
+  Status BackgroundFlush(bool* madeProgress);
+  void CleanupCompaction(CompactionState* compact, Status status);
  Status DoCompactionWork(CompactionState* compact);

  Status OpenCompactionOutputFile(CompactionState* compact);
@@ -206,36 +221,41 @@ class DBImpl : public DB {
  // Removes the file listed in files_to_evict from the table_cache
  void EvictObsoleteFiles(DeletionState& deletion_state);

+  Status DeleteLogFile(uint64_t number);
+
  void PurgeObsoleteWALFiles();

-  Status ListAllWALFiles(const std::string& path,
-                         std::vector<LogFile>* logFiles,
-                         WalFileType type);
+  Status AppendSortedWalsOfType(const std::string& path,
+                                VectorLogPtr& log_files,
+                                WalFileType type);

-  //  Find's all the log files which contain updates with seq no.
-  //  Greater Than or Equal to the requested SequenceNumber
-  Status FindProbableWALFiles(std::vector<LogFile>* const allLogs,
-                              std::vector<LogFile>* const result,
-                              const SequenceNumber target);
+  // Requires: all_logs should be sorted with earliest log file first
+  // Retains all log files in all_logs which contain updates with seq no.
+  // Greater Than or Equal to the requested SequenceNumber.
+  Status RetainProbableWalFiles(VectorLogPtr& all_logs,
+                                const SequenceNumber target);
  //  return true if
-  bool CheckFileExistsAndEmpty(const LogFile& file);
+  bool CheckWalFileExistsAndEmpty(const WalFileType type,
+                                  const uint64_t number);

-  Status ReadFirstRecord(const LogFile& file, WriteBatch* const result);
+  Status ReadFirstRecord(const WalFileType type, const uint64_t number,
+                         WriteBatch* const result);

  Status ReadFirstLine(const std::string& fname, WriteBatch* const batch);

  void PrintStatistics();

-  // dump leveldb.stats to LOG
+  // dump rocksdb.stats to LOG
  void MaybeDumpStats();

  // Return the minimum empty level that could hold the total data in the
  // input level. Return the input level, if such level could not be found.
  int FindMinimumEmptyLevelFitting(int level);

-  // Move the files in the input level to the minimum level that could hold
-  // the data set.
-  void ReFitLevel(int level);
+  // Move the files in the input level to the target level.
+  // If target_level < 0, automatically calculate the minimum level that could
+  // hold the data set.
+  void ReFitLevel(int level, int target_level = -1);

  // Constant after construction
  const InternalFilterPolicy internal_filter_policy_;
@@ -272,6 +292,9 @@ class DBImpl : public DB {
  // count how many background compaction been scheduled or is running?
  int bg_compaction_scheduled_;

+  // number of background memtable flush jobs, submitted to the HIGH pool
+  int bg_flush_scheduled_;
+
  // Has a background stats log thread scheduled?
  bool bg_logstats_scheduled_;

@@ -305,6 +328,10 @@ class DBImpl : public DB {
  // last time stats were dumped to LOG
  std::atomic<uint64_t> last_stats_dump_time_microsec_;

+  // obsolete files will be deleted every this seconds if ttl deletion is
+  // enabled and archive size_limit is disabled.
+  uint64_t default_interval_to_delete_obsolete_WAL_;
+
  // These count the number of microseconds for which MakeRoomForWrite stalls.
  uint64_t stall_level0_slowdown_;
  uint64_t stall_memtable_compaction_;
@@ -384,10 +411,6 @@ class DBImpl : public DB {
  // count of the number of contiguous delaying writes
  int delayed_writes_;

-  // store the last flushed sequence.
-  // Used by transaction log iterator.
-  SequenceNumber last_flushed_sequence_;
-
  // The options to access storage files
  const EnvOptions storage_options_;

@@ -416,7 +439,6 @@ class DBImpl : public DB {
  Status GetImpl(const ReadOptions& options,
                 const Slice& key,
                 std::string* value,
-                 const bool no_io = false,
                 bool* value_found = nullptr);
 };

@@ -427,6 +449,13 @@ extern Options SanitizeOptions(const std::string& db,
                               const InternalFilterPolicy* ipolicy,
                               const Options& src);

-}  // namespace leveldb

-#endif  // STORAGE_LEVELDB_DB_DB_IMPL_H_
+// Determine compression type, based on user options, level of the output
+// file and whether compression is disabled.
+// If enable_compression is false, then compression is always disabled no
+// matter what the values of the other two parameters are.
+// Otherwise, the compression type is determined based on options and level.
+CompressionType GetCompressionType(const Options& options, int level,
+                                   const bool enable_compression);
+
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -21,20 +26,19 @@
 #include "db/table_cache.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
-#include "leveldb/status.h"
-#include "leveldb/table_builder.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/status.h"
+#include "rocksdb/table.h"
 #include "port/port.h"
 #include "table/block.h"
 #include "table/merger.h"
-#include "table/table.h"
 #include "table/two_level_iterator.h"
 #include "util/coding.h"
 #include "util/logging.h"
 #include "util/build_version.h"

-namespace leveldb {
+namespace rocksdb {

 DBImplReadOnly::DBImplReadOnly(const Options& options,
    const std::string& dbname)
@@ -1,10 +1,13 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

-#ifndef STORAGE_LEVELDB_DB_DB_IMPL_READONLY_H_
-#define STORAGE_LEVELDB_DB_DB_IMPL_READONLY_H_
-
+#pragma once
 #include "db/db_impl.h"

 #include <deque>
@@ -12,16 +15,12 @@
 #include "db/dbformat.h"
 #include "db/log_writer.h"
 #include "db/snapshot.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
 #include "port/port.h"
 #include "util/stats_logger.h"

-#ifdef USE_SCRIBE
-#include "scribe/scribe_logger.h"
-#endif
-
-namespace leveldb {
+namespace rocksdb {

 class DBImplReadOnly : public DBImpl {
 public:
@@ -51,7 +50,7 @@ public:
   return Status::NotSupported("Not supported operation in read only mode.");
 }
 virtual void CompactRange(const Slice* begin, const Slice* end,
-                           bool reduce_level = false) {
+                           bool reduce_level = false, int target_level = -1) {
 }
 virtual Status DisableFileDeletions() {
   return Status::NotSupported("Not supported operation in read only mode.");
@@ -60,7 +59,8 @@ public:
   return Status::NotSupported("Not supported operation in read only mode.");
 }
 virtual Status GetLiveFiles(std::vector<std::string>&,
-                             uint64_t* manifest_file_size) {
+                             uint64_t* manifest_file_size,
+                             bool flush_memtable = true) {
   return Status::NotSupported("Not supported operation in read only mode.");
 }
 virtual Status Flush(const FlushOptions& options) {
@@ -76,5 +76,3 @@ private:
 };

 }
-
-#endif
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -8,15 +13,16 @@

 #include "db/filename.h"
 #include "db/dbformat.h"
-#include "leveldb/env.h"
-#include "leveldb/options.h"
-#include "leveldb/iterator.h"
-#include "leveldb/merge_operator.h"
+#include "rocksdb/env.h"
+#include "rocksdb/options.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/merge_operator.h"
 #include "port/port.h"
 #include "util/logging.h"
 #include "util/mutexlock.h"
+#include "util/perf_context_imp.h"

-namespace leveldb {
+namespace rocksdb {

 #if 0
 static void DumpInternalIter(Iterator* iter) {
@@ -57,7 +63,7 @@ class DBIter: public Iterator {
        env_(env),
        logger_(options.info_log),
        user_comparator_(cmp),
-        user_merge_operator_(options.merge_operator),
+        user_merge_operator_(options.merge_operator.get()),
        iter_(iter),
        sequence_(s),
        direction_(kForward),
@@ -65,6 +71,7 @@ class DBIter: public Iterator {
        current_entry_is_merged_(false),
        statistics_(options.statistics) {
    RecordTick(statistics_, NO_ITERATORS, 1);
+    max_skip_ = options.max_sequential_skip_in_iterations;
  }
  virtual ~DBIter() {
    RecordTick(statistics_, NO_ITERATORS, -1);
@@ -129,6 +136,7 @@ class DBIter: public Iterator {
  bool valid_;
  bool current_entry_is_merged_;
  std::shared_ptr<Statistics> statistics_;
+  uint64_t max_skip_;

  // No copying allowed
  DBIter(const DBIter&);
@@ -188,12 +196,14 @@ void DBIter::FindNextUserEntry(bool skipping) {
  assert(iter_->Valid());
  assert(direction_ == kForward);
  current_entry_is_merged_ = false;
+  uint64_t num_skipped = 0;
  do {
    ParsedInternalKey ikey;
    if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
      if (skipping &&
          user_comparator_->Compare(ikey.user_key, saved_key_) <= 0) {
-        // skip this entry
+        num_skipped++; // skip this entry
+        BumpPerfCount(&perf_context.internal_key_skipped_count);
      } else {
        skipping = false;
        switch (ikey.type) {
@@ -202,6 +212,8 @@ void DBIter::FindNextUserEntry(bool skipping) {
            // they are hidden by this deletion.
            SaveKey(ikey.user_key, &saved_key_);
            skipping = true;
+            num_skipped = 0;
+            BumpPerfCount(&perf_context.internal_delete_skipped_count);
            break;
          case kTypeValue:
            valid_ = true;
@@ -212,15 +224,28 @@ void DBIter::FindNextUserEntry(bool skipping) {
            SaveKey(ikey.user_key, &saved_key_);
            current_entry_is_merged_ = true;
            valid_ = true;
-            // Go to a different state machine
-            MergeValuesNewToOld();
-            // TODO: what if !iter_->Valid()
+            MergeValuesNewToOld();  // Go to a different state machine
            return;
+          case kTypeLogData:
+            assert(false);
            break;
        }
      }
    }
-    iter_->Next();
+    // If we have sequentially iterated via numerous keys and still not
+    // found the next user-key, then it is better to seek so that we can
+    // avoid too many key comparisons. We seek to the last occurence of
+    // our current key by looking for sequence number 0.
+    if (skipping && num_skipped > max_skip_) {
+      num_skipped = 0;
+      std::string last_key;
+      AppendInternalKey(&last_key,
+        ParsedInternalKey(Slice(saved_key_), 0, kValueTypeForSeek));
+      iter_->Seek(last_key);
+      RecordTick(statistics_, NUMBER_OF_RESEEKS_IN_ITERATION);
+    } else {
+      iter_->Next();
+    }
  } while (iter_->Valid());
  valid_ = false;
 }
@@ -232,7 +257,11 @@ void DBIter::FindNextUserEntry(bool skipping) {
 // POST: saved_value_ has the merged value for the user key
 //       iter_ points to the next entry (or invalid)
 void DBIter::MergeValuesNewToOld() {
-  // TODO: Is there a way to unite with MergeHelper or other similar code?
+  if (!user_merge_operator_) {
+    Log(logger_, "Options::merge_operator is null.");
+    throw std::logic_error("DBIter::MergeValuesNewToOld() with"
+                           " Options::merge_operator null");
+  }

  // Start the merge process by pushing the first operand
  std::deque<std::string> operands;
@@ -263,8 +292,8 @@ void DBIter::MergeValuesNewToOld() {
      // final result in saved_value_. We are done!
      // ignore corruption if there is any.
      const Slice value = iter_->value();
-      user_merge_operator_->Merge(ikey.user_key, &value, operands,
-                                  &saved_value_, logger_.get());
+      user_merge_operator_->FullMerge(ikey.user_key, &value, operands,
+                                      &saved_value_, logger_.get());
      // iter_ is positioned after put
      iter_->Next();
      return;
@@ -297,8 +326,8 @@ void DBIter::MergeValuesNewToOld() {
  // a deletion marker.
  // feed null as the existing value to the merge operator, such that
  // client can differentiate this scenario and do things accordingly.
-  user_merge_operator_->Merge(ikey.user_key, nullptr, operands,
-                              &saved_value_, logger_.get());
+  user_merge_operator_->FullMerge(saved_key_, nullptr, operands,
+                                  &saved_value_, logger_.get());
 }

 void DBIter::Prev() {
@@ -338,11 +367,13 @@ void DBIter::Prev() {

 void DBIter::FindPrevUserEntry() {
  assert(direction_ == kReverse);
+  uint64_t num_skipped = 0;

  ValueType value_type = kTypeDeletion;
  if (iter_->Valid()) {
    do {
      ParsedInternalKey ikey;
+      bool saved_key_cleared = false;
      if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
        if ((value_type != kTypeDeletion) &&
            user_comparator_->Compare(ikey.user_key, saved_key_) < 0) {
@@ -353,6 +384,7 @@ void DBIter::FindPrevUserEntry() {
        if (value_type == kTypeDeletion) {
          saved_key_.clear();
          ClearSavedValue();
+          saved_key_cleared = true;
        } else {
          Slice raw_value = iter_->value();
          if (saved_value_.capacity() > raw_value.size() + 1048576) {
@@ -363,7 +395,22 @@ void DBIter::FindPrevUserEntry() {
          saved_value_.assign(raw_value.data(), raw_value.size());
        }
      }
-      iter_->Prev();
+      num_skipped++;
+      // If we have sequentially iterated via numerous keys and still not
+      // found the prev user-key, then it is better to seek so that we can
+      // avoid too many key comparisons. We seek to the first occurence of
+      // our current key by looking for max sequence number.
+      if (!saved_key_cleared && num_skipped > max_skip_) {
+        num_skipped = 0;
+        std::string last_key;
+        AppendInternalKey(&last_key,
+          ParsedInternalKey(Slice(saved_key_), kMaxSequenceNumber,
+                            kValueTypeForSeek));
+        iter_->Seek(last_key);
+        RecordTick(statistics_, NUMBER_OF_RESEEKS_IN_ITERATION);
+      } else {
+        iter_->Prev();
+      }
    } while (iter_->Valid());
  }

@@ -431,4 +478,4 @@ Iterator* NewDBIterator(
                    internal_iter, sequence);
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,15 +1,18 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_DB_ITER_H_
-#define STORAGE_LEVELDB_DB_DB_ITER_H_
-
+#pragma once
 #include <stdint.h>
-#include "leveldb/db.h"
+#include "rocksdb/db.h"
 #include "db/dbformat.h"

-namespace leveldb {
+namespace rocksdb {

 // Return a new iterator that converts internal keys (yielded by
 // "*internal_iter") that were live at the specified "sequence" number
@@ -22,6 +25,4 @@ extern Iterator* NewDBIterator(
    Iterator* internal_iter,
    const SequenceNumber& sequence);

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_DB_ITER_H_
+}  // namespace rocksdb
@@ -1,22 +1,25 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef LEVELDB_STORAGE_DB_DB_STATISTICS_H_
-#define LEVELDB_STORAGE_DB_DB_STATISTICS_H_
-
+#pragma once
 #include <cassert>
 #include <stdlib.h>
 #include <vector>
 #include <memory>

-#include "leveldb/statistics.h"
+#include "rocksdb/statistics.h"
 #include "util/histogram.h"
 #include "port/port.h"
 #include "util/mutexlock.h"


-namespace leveldb {
+namespace rocksdb {

 class DBStatistics: public Statistics {
 public:
@@ -30,6 +33,11 @@ class DBStatistics: public Statistics {
    return allTickers_[tickerType].getCount();
  }

+  virtual void setTickerCount(Tickers tickerType, uint64_t count) {
+    assert(tickerType < TICKER_ENUM_MAX);
+    allTickers_[tickerType].setTickerCount(count);
+  }
+
  virtual void recordTick(Tickers tickerType, uint64_t count) {
    assert(tickerType < TICKER_ENUM_MAX);
    allTickers_[tickerType].recordTick(count);
@@ -54,8 +62,4 @@ std::shared_ptr<Statistics> CreateDBStatistics() {
  return std::make_shared<DBStatistics>();
 }

-} // namespace leveldb
-
-#endif // LEVELDB_STORAGE_DB_DB_STATISTICS_H_
-
-
+} // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -7,12 +12,12 @@
 #include <stdint.h>
 #include <stdio.h>
 #include "db/version_set.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
 #include "port/port.h"
 #include "util/mutexlock.h"

-namespace leveldb {
+namespace rocksdb {

 void DBImpl::MaybeScheduleLogDBDeployStats() {

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -6,8 +11,9 @@
 #include "db/dbformat.h"
 #include "port/port.h"
 #include "util/coding.h"
+#include "util/perf_context_imp.h"

-namespace leveldb {
+namespace rocksdb {

 static uint64_t PackSequenceAndType(uint64_t seq, ValueType t) {
  assert(seq <= kMaxSequenceNumber);
@@ -53,6 +59,7 @@ int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
  //    decreasing sequence number
  //    decreasing type (though sequence# should be enough to disambiguate)
  int r = user_comparator_->Compare(ExtractUserKey(akey), ExtractUserKey(bkey));
+  BumpPerfCount(&perf_context.user_key_comparison_count);
  if (r == 0) {
    const uint64_t anum = DecodeFixed64(akey.data() + akey.size() - 8);
    const uint64_t bnum = DecodeFixed64(bkey.data() + bkey.size() - 8);
@@ -137,4 +144,4 @@ LookupKey::LookupKey(const Slice& user_key, SequenceNumber s) {
  end_ = dst;
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,21 +1,24 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_FORMAT_H_
-#define STORAGE_LEVELDB_DB_FORMAT_H_
-
+#pragma once
 #include <stdio.h>
-#include "leveldb/comparator.h"
-#include "leveldb/db.h"
-#include "leveldb/filter_policy.h"
-#include "leveldb/slice.h"
-#include "leveldb/table_builder.h"
-#include "leveldb/types.h"
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/filter_policy.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/table.h"
+#include "rocksdb/types.h"
 #include "util/coding.h"
 #include "util/logging.h"

-namespace leveldb {
+namespace rocksdb {

 class InternalKey;

@@ -25,7 +28,8 @@ class InternalKey;
 enum ValueType {
  kTypeDeletion = 0x0,
  kTypeValue = 0x1,
-  kTypeMerge = 0x2
+  kTypeMerge = 0x2,
+  kTypeLogData = 0x3
 };
 // kValueTypeForSeek defines the ValueType that should be passed when
 // constructing a ParsedInternalKey object for seeking to a particular
@@ -89,7 +93,7 @@ class InternalKeyComparator : public Comparator {
  std::string name_;
 public:
  explicit InternalKeyComparator(const Comparator* c) : user_comparator_(c),
-    name_("leveldb.InternalKeyComparator:" +
+    name_("rocksdb.InternalKeyComparator:" +
          std::string(user_comparator_->Name())) {
  }

@@ -173,6 +177,15 @@ inline void UpdateInternalKey(char* internal_key,
  EncodeFixed64(seqtype, newval);
 }

+// Get the sequence number from the internal key
+inline uint64_t GetInternalKeySeqno(const Slice& internal_key) {
+  const size_t n = internal_key.size();
+  assert(n >= 8);
+  uint64_t num = DecodeFixed64(internal_key.data() + n - 8);
+  return num >> 8;
+}
+
+
 // A helper class useful for DBImpl::Get()
 class LookupKey {
 public:
@@ -213,6 +226,4 @@ inline LookupKey::~LookupKey() {
  if (start_ != space_) delete[] start_;
 }

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_FORMAT_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -6,7 +11,7 @@
 #include "util/logging.h"
 #include "util/testharness.h"

-namespace leveldb {
+namespace rocksdb {

 static std::string IKey(const std::string& user_key,
                        uint64_t seq,
@@ -105,8 +110,8 @@ TEST(FormatTest, InternalKeyShortestSuccessor) {
            ShortSuccessor(IKey("\xff\xff", 100, kTypeValue)));
 }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -0,0 +1,230 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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 "rocksdb/db.h"
+#include "db/db_impl.h"
+#include "db/filename.h"
+#include "db/version_set.h"
+#include "db/write_batch_internal.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+#include "rocksdb/env.h"
+#include "rocksdb/transaction_log.h"
+#include <vector>
+#include <stdlib.h>
+#include <map>
+#include <string>
+
+namespace rocksdb {
+
+class DeleteFileTest {
+ public:
+  std::string dbname_;
+  Options options_;
+  DB* db_;
+  Env* env_;
+  int numlevels_;
+
+  DeleteFileTest() {
+    db_ = nullptr;
+    env_ = Env::Default();
+    options_.write_buffer_size = 1024*1024*1000;
+    options_.target_file_size_base = 1024*1024*1000;
+    options_.max_bytes_for_level_base = 1024*1024*1000;
+    options_.WAL_ttl_seconds = 300; // Used to test log files
+    options_.WAL_size_limit_MB = 1024; // Used to test log files
+    dbname_ = test::TmpDir() + "/deletefile_test";
+    DestroyDB(dbname_, options_);
+    numlevels_ = 7;
+    ASSERT_OK(ReopenDB(true));
+  }
+
+  Status ReopenDB(bool create) {
+    delete db_;
+    if (create) {
+      DestroyDB(dbname_, options_);
+    }
+    db_ = nullptr;
+    options_.create_if_missing = create;
+    return DB::Open(options_, dbname_, &db_);
+  }
+
+  void CloseDB() {
+    delete db_;
+  }
+
+  void AddKeys(int numkeys, int startkey = 0) {
+    WriteOptions options;
+    options.sync = false;
+    ReadOptions roptions;
+    for (int i = startkey; i < (numkeys + startkey) ; i++) {
+      std::string temp = std::to_string(i);
+      Slice key(temp);
+      Slice value(temp);
+      ASSERT_OK(db_->Put(options, key, value));
+    }
+  }
+
+  int numKeysInLevels(
+    std::vector<LiveFileMetaData> &metadata,
+    std::vector<int> *keysperlevel = nullptr) {
+
+    if (keysperlevel != nullptr) {
+      keysperlevel->resize(numlevels_);
+    }
+
+    int numKeys = 0;
+    for (size_t i = 0; i < metadata.size(); i++) {
+      int startkey = atoi(metadata[i].smallestkey.c_str());
+      int endkey = atoi(metadata[i].largestkey.c_str());
+      int numkeysinfile = (endkey - startkey + 1);
+      numKeys += numkeysinfile;
+      if (keysperlevel != nullptr) {
+        (*keysperlevel)[(int)metadata[i].level] += numkeysinfile;
+      }
+      fprintf(stderr, "level %d name %s smallest %s largest %s\n",
+              metadata[i].level, metadata[i].name.c_str(),
+              metadata[i].smallestkey.c_str(),
+              metadata[i].largestkey.c_str());
+    }
+    return numKeys;
+  }
+
+  void CreateTwoLevels() {
+    AddKeys(50000, 10000);
+    DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
+    ASSERT_OK(dbi->TEST_FlushMemTable());
+    ASSERT_OK(dbi->TEST_WaitForFlushMemTable());
+
+    AddKeys(50000, 10000);
+    ASSERT_OK(dbi->TEST_FlushMemTable());
+    ASSERT_OK(dbi->TEST_WaitForFlushMemTable());
+  }
+
+};
+
+TEST(DeleteFileTest, AddKeysAndQueryLevels) {
+  CreateTwoLevels();
+  std::vector<LiveFileMetaData> metadata;
+  std::vector<int> keysinlevel;
+  db_->GetLiveFilesMetaData(&metadata);
+
+  std::string level1file = "";
+  int level1keycount = 0;
+  std::string level2file = "";
+  int level2keycount = 0;
+  int level1index = 0;
+  int level2index = 1;
+
+  ASSERT_EQ((int)metadata.size(), 2);
+  if (metadata[0].level == 2) {
+    level1index = 1;
+    level2index = 0;
+  }
+
+  level1file = metadata[level1index].name;
+  int startkey = atoi(metadata[level1index].smallestkey.c_str());
+  int endkey = atoi(metadata[level1index].largestkey.c_str());
+  level1keycount = (endkey - startkey + 1);
+  level2file = metadata[level2index].name;
+  startkey = atoi(metadata[level2index].smallestkey.c_str());
+  endkey = atoi(metadata[level2index].largestkey.c_str());
+  level2keycount = (endkey - startkey + 1);
+
+  // COntrolled setup. Levels 1 and 2 should both have 50K files.
+  // This is a little fragile as it depends on the current
+  // compaction heuristics.
+  ASSERT_EQ(level1keycount, 50000);
+  ASSERT_EQ(level2keycount, 50000);
+
+  Status status = db_->DeleteFile("0.sst");
+  ASSERT_TRUE(status.IsInvalidArgument());
+
+  // intermediate level files cannot be deleted.
+  status = db_->DeleteFile(level1file);
+  ASSERT_TRUE(status.IsInvalidArgument());
+
+  // Lowest level file deletion should succeed.
+  ASSERT_OK(db_->DeleteFile(level2file));
+
+  CloseDB();
+}
+
+TEST(DeleteFileTest, DeleteFileWithIterator) {
+  CreateTwoLevels();
+  ReadOptions options;
+  Iterator* it = db_->NewIterator(options);
+  std::vector<LiveFileMetaData> metadata;
+  db_->GetLiveFilesMetaData(&metadata);
+
+  std::string level2file = "";
+
+  ASSERT_EQ((int)metadata.size(), 2);
+  if (metadata[0].level == 1) {
+    level2file = metadata[1].name;
+  } else {
+    level2file = metadata[0].name;
+  }
+
+  Status status = db_->DeleteFile(level2file);
+  fprintf(stdout, "Deletion status %s: %s\n",
+          level2file.c_str(), status.ToString().c_str());
+  ASSERT_TRUE(status.ok());
+  it->SeekToFirst();
+  int numKeysIterated = 0;
+  while(it->Valid()) {
+    numKeysIterated++;
+    it->Next();
+  }
+  ASSERT_EQ(numKeysIterated, 50000);
+  delete it;
+  CloseDB();
+}
+
+TEST(DeleteFileTest, DeleteLogFiles) {
+  AddKeys(10, 0);
+  VectorLogPtr logfiles;
+  db_->GetSortedWalFiles(logfiles);
+  ASSERT_GT(logfiles.size(), 0UL);
+  // Take the last log file which is expected to be alive and try to delete it
+  // Should not succeed because live logs are not allowed to be deleted
+  std::unique_ptr<LogFile> alive_log = std::move(logfiles.back());
+  ASSERT_EQ(alive_log->Type(), kAliveLogFile);
+  ASSERT_TRUE(env_->FileExists(dbname_ + "/" + alive_log->PathName()));
+  fprintf(stdout, "Deleting alive log file %s\n",
+          alive_log->PathName().c_str());
+  ASSERT_TRUE(!db_->DeleteFile(alive_log->PathName()).ok());
+  ASSERT_TRUE(env_->FileExists(dbname_ + "/" + alive_log->PathName()));
+  logfiles.clear();
+
+  // Call Flush to bring about a new working log file and add more keys
+  // Call Flush again to flush out memtable and move alive log to archived log
+  // and try to delete the archived log file
+  FlushOptions fopts;
+  db_->Flush(fopts);
+  AddKeys(10, 0);
+  db_->Flush(fopts);
+  db_->GetSortedWalFiles(logfiles);
+  ASSERT_GT(logfiles.size(), 0UL);
+  std::unique_ptr<LogFile> archived_log = std::move(logfiles.front());
+  ASSERT_EQ(archived_log->Type(), kArchivedLogFile);
+  ASSERT_TRUE(env_->FileExists(dbname_ + "/" + archived_log->PathName()));
+  fprintf(stdout, "Deleting archived log file %s\n",
+          archived_log->PathName().c_str());
+  ASSERT_OK(db_->DeleteFile(archived_log->PathName()));
+  ASSERT_TRUE(!env_->FileExists(dbname_ + "/" + archived_log->PathName()));
+  CloseDB();
+}
+
+} //namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}
+
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -7,10 +12,10 @@
 #include <ctype.h>
 #include <stdio.h>
 #include "db/dbformat.h"
-#include "leveldb/env.h"
+#include "rocksdb/env.h"
 #include "util/logging.h"

-namespace leveldb {
+namespace rocksdb {

 // Given a path, flatten the path name by replacing all chars not in
 // {[0-9,a-z,A-Z,-,_,.]} with _. And append '\0' at the end.
@@ -57,12 +62,12 @@ std::string LogFileName(const std::string& name, uint64_t number) {
  return MakeFileName(name, number, "log");
 }

-std::string ArchivalDirectory(const std::string& dbname) {
-  return dbname + "/" + ARCHIVAL_DIR;
+std::string ArchivalDirectory(const std::string& dir) {
+  return dir + "/" + ARCHIVAL_DIR;
 }
 std::string ArchivedLogFileName(const std::string& name, uint64_t number) {
  assert(number > 0);
-  return MakeFileName(name + "/archive", number, "log");
+  return MakeFileName(name + "/" + ARCHIVAL_DIR, number, "log");
 }

 std::string TableFileName(const std::string& name, uint64_t number) {
@@ -87,7 +92,7 @@ std::string LockFileName(const std::string& dbname) {
 }

 std::string TempFileName(const std::string& dbname, uint64_t number) {
-  assert(number > 0);
+  assert(number >= 0);
  return MakeFileName(dbname, number, "dbtmp");
 }

@@ -122,7 +127,12 @@ std::string MetaDatabaseName(const std::string& dbname, uint64_t number) {
  return dbname + buf;
 }

+std::string IdentityFileName(const std::string& dbname) {
+  return dbname + "/IDENTITY";
+}
+
 // Owned filenames have the form:
+//    dbname/IDENTITY
 //    dbname/CURRENT
 //    dbname/LOCK
 //    dbname/LOG
@@ -130,11 +140,19 @@ std::string MetaDatabaseName(const std::string& dbname, uint64_t number) {
 //    dbname/MANIFEST-[0-9]+
 //    dbname/[0-9]+.(log|sst)
 //    dbname/METADB-[0-9]+
+//    Disregards / at the beginning
 bool ParseFileName(const std::string& fname,
                   uint64_t* number,
-                   FileType* type) {
+                   FileType* type,
+                   WalFileType* log_type) {
  Slice rest(fname);
-  if (rest == "CURRENT") {
+  if (fname.length() > 1 && fname[0] == '/') {
+    rest.remove_prefix(1);
+  }
+  if (rest == "IDENTITY") {
+    *number = 0;
+    *type = kIdentityFile;
+  } else if (rest == "CURRENT") {
    *number = 0;
    *type = kCurrentFile;
  } else if (rest == "LOCK") {
@@ -177,6 +195,17 @@ bool ParseFileName(const std::string& fname,
  } else {
    // Avoid strtoull() to keep filename format independent of the
    // current locale
+    bool archive_dir_found = false;
+    if (rest.starts_with(ARCHIVAL_DIR)) {
+      if (rest.size() <= ARCHIVAL_DIR.size()) {
+        return false;
+      }
+      rest.remove_prefix(ARCHIVAL_DIR.size() + 1); // Add 1 to remove / also
+      if (log_type) {
+        *log_type = kArchivedLogFile;
+      }
+      archive_dir_found = true;
+    }
    uint64_t num;
    if (!ConsumeDecimalNumber(&rest, &num)) {
      return false;
@@ -184,6 +213,11 @@ bool ParseFileName(const std::string& fname,
    Slice suffix = rest;
    if (suffix == Slice(".log")) {
      *type = kLogFile;
+      if (log_type && !archive_dir_found) {
+        *log_type = kAliveLogFile;
+      }
+    } else if (archive_dir_found) {
+      return false; // Archive dir can contain only log files
    } else if (suffix == Slice(".sst")) {
      *type = kTableFile;
    } else if (suffix == Slice(".dbtmp")) {
@@ -214,4 +248,19 @@ Status SetCurrentFile(Env* env, const std::string& dbname,
  return s;
 }

-}  // namespace leveldb
+Status SetIdentityFile(Env* env, const std::string& dbname) {
+  std::string id = env->GenerateUniqueId();
+  assert(!id.empty());
+  // Reserve the filename dbname/000000.dbtmp for the temporary identity file
+  std::string tmp = TempFileName(dbname, 0);
+  Status s = WriteStringToFileSync(env, id, tmp);
+  if (s.ok()) {
+    s = env->RenameFile(tmp, IdentityFileName(dbname));
+  }
+  if (!s.ok()) {
+    env->DeleteFile(tmp);
+  }
+  return s;
+}
+
+}  // namespace rocksdb
@@ -1,19 +1,23 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
 //
 // File names used by DB code

-#ifndef STORAGE_LEVELDB_DB_FILENAME_H_
-#define STORAGE_LEVELDB_DB_FILENAME_H_
-
+#pragma once
 #include <stdint.h>
 #include <string>
-#include "leveldb/slice.h"
-#include "leveldb/status.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/status.h"
+#include "rocksdb/transaction_log.h"
 #include "port/port.h"

-namespace leveldb {
+namespace rocksdb {

 class Env;

@@ -25,7 +29,8 @@ enum FileType {
  kCurrentFile,
  kTempFile,
  kInfoLogFile,  // Either the current one, or an old one
-  kMetaDatabase
+  kMetaDatabase,
+  kIdentityFile
 };

 // Return the name of the log file with the specified number
@@ -79,19 +84,25 @@ extern std::string OldInfoLogFileName(const std::string& dbname, uint64_t ts,
 extern std::string MetaDatabaseName(const std::string& dbname,
                                    uint64_t number);

-// If filename is a leveldb file, store the type of the file in *type.
+// Return the name of the Identity file which stores a unique number for the db
+// that will get regenerated if the db loses all its data and is recreated fresh
+// either from a backup-image or empty
+extern std::string IdentityFileName(const std::string& dbname);
+
+// If filename is a rocksdb file, store the type of the file in *type.
 // The number encoded in the filename is stored in *number.  If the
 // filename was successfully parsed, returns true.  Else return false.
 extern bool ParseFileName(const std::string& filename,
                          uint64_t* number,
-                          FileType* type);
+                          FileType* type,
+                          WalFileType* log_type = nullptr);

 // Make the CURRENT file point to the descriptor file with the
 // specified number.
 extern Status SetCurrentFile(Env* env, const std::string& dbname,
                             uint64_t descriptor_number);

+// Make the IDENTITY file for the db
+extern Status SetIdentityFile(Env* env, const std::string& dbname);

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_FILENAME_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -9,7 +14,7 @@
 #include "util/logging.h"
 #include "util/testharness.h"

-namespace leveldb {
+namespace rocksdb {

 class FileNameTest { };

@@ -128,8 +133,8 @@ TEST(FileNameTest, Construction) {
  ASSERT_EQ(kMetaDatabase, type);
 }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,48 +0,0 @@
-// Copyright 2008-present Facebook. All Rights Reserved.
-
-#ifndef STORAGE_LEVELDB_DB_LOG_FILE_H_
-#define STORAGE_LEVELDB_DB_LOG_FILE_H_
-
-namespace leveldb {
-
-enum  WalFileType {
-  kArchivedLogFile = 0,
-  kAliveLogFile = 1
-} ;
-
-class LogFile {
-
- public:
-  uint64_t logNumber;
-  WalFileType type;
-
-  LogFile(uint64_t logNum,WalFileType logType) :
-    logNumber(logNum),
-    type(logType) {}
-
-  LogFile(const LogFile& that) {
-   logNumber = that.logNumber;
-   type = that.type;
-  }
-
-  bool operator < (const LogFile& that) const {
-    return logNumber < that.logNumber;
-  }
-
-  std::string ToString() const {
-    char response[100];
-    const char* typeOfLog;
-    if (type == kAliveLogFile) {
-      typeOfLog = "Alive Log";
-    } else {
-      typeOfLog = "Archived Log";
-    }
-    sprintf(response,
-            "LogNumber  : %ld LogType : %s",
-            logNumber,
-            typeOfLog);
-    return std::string(response);
-  }
-};
-}  //  namespace leveldb
-#endif  // STORAGE_LEVELDB_DB_LOG_FILE_H_
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -5,10 +10,8 @@
 // Log format information shared by reader and writer.
 // See ../doc/log_format.txt for more detail.

-#ifndef STORAGE_LEVELDB_DB_LOG_FORMAT_H_
-#define STORAGE_LEVELDB_DB_LOG_FORMAT_H_
-
-namespace leveldb {
+#pragma once
+namespace rocksdb {
 namespace log {

 enum RecordType {
@@ -30,6 +33,4 @@ static const unsigned int kBlockSize = 32768;
 static const int kHeaderSize = 4 + 1 + 2;

 }  // namespace log
-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_LOG_FORMAT_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -5,11 +10,11 @@
 #include "db/log_reader.h"

 #include <stdio.h>
-#include "leveldb/env.h"
+#include "rocksdb/env.h"
 #include "util/coding.h"
 #include "util/crc32c.h"

-namespace leveldb {
+namespace rocksdb {
 namespace log {

 Reader::Reporter::~Reporter() {
@@ -256,4 +261,4 @@ unsigned int Reader::ReadPhysicalRecord(Slice* result) {
 }

 }  // namespace log
-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,18 +1,21 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_LOG_READER_H_
-#define STORAGE_LEVELDB_DB_LOG_READER_H_
-
+#pragma once
 #include <memory>
 #include <stdint.h>

 #include "db/log_format.h"
-#include "leveldb/slice.h"
-#include "leveldb/status.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/status.h"

-namespace leveldb {
+namespace rocksdb {

 class SequentialFile;
 using std::unique_ptr;
@@ -118,6 +121,4 @@ class Reader {
 };

 }  // namespace log
-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_LOG_READER_H_
+}  // namespace rocksdb
@@ -1,16 +1,21 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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/log_reader.h"
 #include "db/log_writer.h"
-#include "leveldb/env.h"
+#include "rocksdb/env.h"
 #include "util/coding.h"
 #include "util/crc32c.h"
 #include "util/random.h"
 #include "util/testharness.h"

-namespace leveldb {
+namespace rocksdb {
 namespace log {

 // Construct a string of the specified length made out of the supplied
@@ -516,8 +521,8 @@ TEST(LogTest, ReadPastEnd) {
 }

 }  // namespace log
-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -5,11 +10,11 @@
 #include "db/log_writer.h"

 #include <stdint.h>
-#include "leveldb/env.h"
+#include "rocksdb/env.h"
 #include "util/coding.h"
 #include "util/crc32c.h"

-namespace leveldb {
+namespace rocksdb {
 namespace log {

 Writer::Writer(unique_ptr<WritableFile>&& dest)
@@ -100,4 +105,4 @@ Status Writer::EmitPhysicalRecord(RecordType t, const char* ptr, size_t n) {
 }

 }  // namespace log
-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,17 +1,20 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_LOG_WRITER_H_
-#define STORAGE_LEVELDB_DB_LOG_WRITER_H_
-
+#pragma once
 #include <memory>
 #include <stdint.h>
 #include "db/log_format.h"
-#include "leveldb/slice.h"
-#include "leveldb/status.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/status.h"

-namespace leveldb {
+namespace rocksdb {

 class WritableFile;

@@ -49,6 +52,4 @@ class Writer {
 };

 }  // namespace log
-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_LOG_WRITER_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -7,21 +12,25 @@
 #include <memory>

 #include "db/dbformat.h"
-#include "leveldb/comparator.h"
-#include "leveldb/env.h"
-#include "leveldb/iterator.h"
-#include "leveldb/merge_operator.h"
+#include "rocksdb/comparator.h"
+#include "rocksdb/env.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/merge_operator.h"
 #include "util/coding.h"
+#include "util/mutexlock.h"
+#include "util/murmurhash.h"

-namespace leveldb {
-
-static Slice GetLengthPrefixedSlice(const char* data) {
-  uint32_t len;
-  const char* p = data;
-  p = GetVarint32Ptr(p, p + 5, &len);  // +5: we assume "p" is not corrupted
-  return Slice(p, len);
+namespace std {
+template <>
+struct hash<rocksdb::Slice> {
+  size_t operator()(const rocksdb::Slice& slice) const {
+    return MurmurHash(slice.data(), slice.size(), 0);
+  }
+};
 }

+namespace rocksdb {
+
 MemTable::MemTable(const InternalKeyComparator& cmp,
                   std::shared_ptr<MemTableRepFactory> table_factory,
                   int numlevel,
@@ -35,14 +44,19 @@ MemTable::MemTable(const InternalKeyComparator& cmp,
      file_number_(0),
      edit_(numlevel),
      first_seqno_(0),
-      mem_logfile_number_(0) { }
+      mem_next_logfile_number_(0),
+      mem_logfile_number_(0),
+      locks_(options.inplace_update_support
+             ? options.inplace_update_num_locks
+             : 0) { }

 MemTable::~MemTable() {
  assert(refs_ == 0);
 }

 size_t MemTable::ApproximateMemoryUsage() {
-  return arena_impl_.ApproximateMemoryUsage();
+  return arena_impl_.ApproximateMemoryUsage() +
+    table_->ApproximateMemoryUsage();
 }

 int MemTable::KeyComparator::operator()(const char* aptr, const char* bptr)
@@ -53,6 +67,11 @@ int MemTable::KeyComparator::operator()(const char* aptr, const char* bptr)
  return comparator.Compare(a, b);
 }

+Slice MemTableRep::UserKey(const char* key) const {
+  Slice slice = GetLengthPrefixedSlice(key);
+  return Slice(slice.data(), slice.size() - 8);
+}
+
 // Encode a suitable internal key target for "target" and return it.
 // Uses *scratch as scratch space, and the returned pointer will point
 // into this scratch space.
@@ -65,8 +84,16 @@ static const char* EncodeKey(std::string* scratch, const Slice& target) {

 class MemTableIterator: public Iterator {
 public:
-  explicit MemTableIterator(MemTableRep* table)
-    : iter_(table->GetIterator()) { }
+  MemTableIterator(MemTableRep* table, const ReadOptions& options)
+    : iter_() {
+    if (options.prefix) {
+      iter_ = table->GetPrefixIterator(*options.prefix);
+    } else if (options.prefix_seek) {
+      iter_ = table->GetDynamicPrefixIterator();
+    } else {
+      iter_ = table->GetIterator();
+    }
+  }

  virtual bool Valid() const { return iter_->Valid(); }
  virtual void Seek(const Slice& k) { iter_->Seek(EncodeKey(&tmp_, k)); }
@@ -93,8 +120,12 @@ class MemTableIterator: public Iterator {
  void operator=(const MemTableIterator&);
 };

-Iterator* MemTable::NewIterator() {
-  return new MemTableIterator(table_.get());
+Iterator* MemTable::NewIterator(const ReadOptions& options) {
+  return new MemTableIterator(table_.get(), options);
+}
+
+port::RWMutex* MemTable::GetLock(const Slice& key) {
+  return &locks_[std::hash<Slice>()(key) % locks_.size()];
 }

 void MemTable::Add(SequenceNumber s, ValueType type,
@@ -132,14 +163,15 @@ void MemTable::Add(SequenceNumber s, ValueType type,
 bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
                   std::deque<std::string>* operands, const Options& options) {
  Slice memkey = key.memtable_key();
-  std::shared_ptr<MemTableRep::Iterator> iter(table_.get()->GetIterator());
+  std::shared_ptr<MemTableRep::Iterator> iter(
+    table_->GetIterator(key.user_key()));
  iter->Seek(memkey.data());

  // It is the caller's responsibility to allocate/delete operands list
  assert(operands != nullptr);

  bool merge_in_progress = s->IsMergeInProgress();
-  auto merge_operator = options.merge_operator;
+  auto merge_operator = options.merge_operator.get();
  auto logger = options.info_log;
  std::string merge_result;

@@ -155,33 +187,40 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
    // all entries with overly large sequence numbers.
    const char* entry = iter->key();
    uint32_t key_length;
-    const char* key_ptr = GetVarint32Ptr(entry, entry+5, &key_length);
+    const char* key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length);
    if (comparator_.comparator.user_comparator()->Compare(
-            Slice(key_ptr, key_length - 8),
-            key.user_key()) == 0) {
+        Slice(key_ptr, key_length - 8), key.user_key()) == 0) {
      // Correct user key
      const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8);
      switch (static_cast<ValueType>(tag & 0xff)) {
        case kTypeValue: {
+          if (options.inplace_update_support) {
+            GetLock(key.user_key())->ReadLock();
+          }
          Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
          *s = Status::OK();
          if (merge_in_progress) {
            assert(merge_operator);
-            if (!merge_operator->Merge(key.user_key(), &v, *operands,
-                                       value, logger.get())) {
+            if (!merge_operator->FullMerge(key.user_key(), &v, *operands,
+                                           value, logger.get())) {
+              RecordTick(options.statistics, NUMBER_MERGE_FAILURES);
              *s = Status::Corruption("Error: Could not perform merge.");
            }
          } else {
            value->assign(v.data(), v.size());
          }
+          if (options.inplace_update_support) {
+            GetLock(key.user_key())->Unlock();
+          }
          return true;
        }
        case kTypeDeletion: {
          if (merge_in_progress) {
            assert(merge_operator);
            *s = Status::OK();
-            if (!merge_operator->Merge(key.user_key(), nullptr, *operands,
-                                       value, logger.get())) {
+            if (!merge_operator->FullMerge(key.user_key(), nullptr, *operands,
+                                           value, logger.get())) {
+              RecordTick(options.statistics, NUMBER_MERGE_FAILURES);
              *s = Status::Corruption("Error: Could not perform merge.");
            }
          } else {
@@ -209,6 +248,9 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
          }
          break;
        }
+        case kTypeLogData:
+          assert(false);
+          break;
      }
    } else {
      // exit loop if user key does not match
@@ -224,4 +266,65 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
  return false;
 }

-}  // namespace leveldb
+bool MemTable::Update(SequenceNumber seq, ValueType type,
+                      const Slice& key,
+                      const Slice& value) {
+  LookupKey lkey(key, seq);
+  Slice memkey = lkey.memtable_key();
+
+  std::shared_ptr<MemTableRep::Iterator> iter(
+    table_.get()->GetIterator(lkey.user_key()));
+  iter->Seek(memkey.data());
+
+  if (iter->Valid()) {
+    // entry format is:
+    //    klength  varint32
+    //    userkey  char[klength-8]
+    //    tag      uint64
+    //    vlength  varint32
+    //    value    char[vlength]
+    // Check that it belongs to same user key.  We do not check the
+    // sequence number since the Seek() call above should have skipped
+    // all entries with overly large sequence numbers.
+    const char* entry = iter->key();
+    uint32_t key_length;
+    const char* key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length);
+    if (comparator_.comparator.user_comparator()->Compare(
+        Slice(key_ptr, key_length - 8), lkey.user_key()) == 0) {
+      // Correct user key
+      const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8);
+      switch (static_cast<ValueType>(tag & 0xff)) {
+        case kTypeValue: {
+          uint32_t vlength;
+          GetVarint32Ptr(key_ptr + key_length,
+                         key_ptr + key_length+5, &vlength);
+          // Update value, if newValue size  <= curValue size
+          if (value.size() <= vlength) {
+            char* p = EncodeVarint32(const_cast<char*>(key_ptr) + key_length,
+                                     value.size());
+            WriteLock wl(GetLock(lkey.user_key()));
+            memcpy(p, value.data(), value.size());
+            assert(
+              (p + value.size()) - entry ==
+              (unsigned) (VarintLength(key_length) +
+                          key_length +
+                          VarintLength(value.size()) +
+                          value.size())
+            );
+            return true;
+          }
+        }
+        default:
+          // If the latest value is kTypeDeletion, kTypeMerge or kTypeLogData
+          // then we probably don't have enough space to update in-place
+          // Maybe do something later
+          // Return false, and do normal Add()
+          return false;
+      }
+    }
+  }
+
+  // Key doesn't exist
+  return false;
+}
+}  // namespace rocksdb
@@ -1,21 +1,24 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_MEMTABLE_H_
-#define STORAGE_LEVELDB_DB_MEMTABLE_H_
-
+#pragma once
 #include <string>
 #include <memory>
 #include <deque>
-#include "leveldb/db.h"
 #include "db/dbformat.h"
 #include "db/skiplist.h"
 #include "db/version_set.h"
-#include "leveldb/memtablerep.h"
+#include "rocksdb/db.h"
+#include "rocksdb/memtablerep.h"
 #include "util/arena_impl.h"

-namespace leveldb {
+namespace rocksdb {

 class Mutex;
 class MemTableIterator;
@@ -61,7 +64,15 @@ class MemTable {
  // while the returned iterator is live.  The keys returned by this
  // iterator are internal keys encoded by AppendInternalKey in the
  // db/dbformat.{h,cc} module.
-  Iterator* NewIterator();
+  //
+  // If options.prefix is supplied, it is passed to the underlying MemTableRep
+  // as a hint that the iterator only need to support access to keys with that
+  // specific prefix.
+  // If options.prefix is not supplied and options.prefix_seek is set, the
+  // iterator is not bound to a specific prefix. However, the semantics of
+  // Seek is changed - the result might only include keys with the same prefix
+  // as the seek-key.
+  Iterator* NewIterator(const ReadOptions& options = ReadOptions());

  // Add an entry into memtable that maps key to value at the
  // specified sequence number and with the specified type.
@@ -81,6 +92,16 @@ class MemTable {
  bool Get(const LookupKey& key, std::string* value, Status* s,
           std::deque<std::string>* operands, const Options& options);

+  // Update the value and return status ok,
+  //   if key exists in current memtable
+  //     if new sizeof(new_value) <= sizeof(old_value) &&
+  //       old_value for that key is a put i.e. kTypeValue
+  //     else return false, and status - NotUpdatable()
+  //   else return false, and status - NotFound()
+  bool Update(SequenceNumber seq, ValueType type,
+              const Slice& key,
+              const Slice& value);
+
  // Returns the edits area that is needed for flushing the memtable
  VersionEdit* GetEdits() { return &edit_; }

@@ -88,6 +109,14 @@ class MemTable {
  // into the memtable
  SequenceNumber GetFirstSequenceNumber() { return first_seqno_; }

+  // Returns the next active logfile number when this memtable is about to
+  // be flushed to storage
+  uint64_t GetNextLogNumber() { return mem_next_logfile_number_; }
+
+  // Sets the next active logfile number when this memtable is about to
+  // be flushed to storage
+  void SetNextLogNumber(uint64_t num) { mem_next_logfile_number_ = num; }
+
  // Returns the logfile number that can be safely deleted when this
  // memstore is flushed to storage
  uint64_t GetLogNumber() { return mem_logfile_number_; }
@@ -96,6 +125,9 @@ class MemTable {
  // memstore is flushed to storage
  void SetLogNumber(uint64_t num) { mem_logfile_number_ = num; }

+  // Notify the underlying storage that no more items will be added
+  void MarkImmutable() { table_->MarkReadOnly(); }
+
 private:
  ~MemTable();  // Private since only Unref() should be used to delete it
  friend class MemTableIterator;
@@ -120,13 +152,21 @@ class MemTable {
  SequenceNumber first_seqno_;

  // The log files earlier than this number can be deleted.
+  uint64_t mem_next_logfile_number_;
+
+  // The log file that backs this memtable (to be deleted when
+  // memtable flush is done)
  uint64_t mem_logfile_number_;

+  // rw locks for inplace updates
+  std::vector<port::RWMutex> locks_;
+
  // No copying allowed
  MemTable(const MemTable&);
  void operator=(const MemTable&);
+
+  // Get the lock associated for the key
+  port::RWMutex* GetLock(const Slice& key);
 };

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_MEMTABLE_H_
+}  // namespace rocksdb
@@ -1,16 +1,18 @@
-// Copyright (c) 2012 Facebook.
-
-
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #include "db/memtablelist.h"

 #include <string>
-#include "leveldb/db.h"
+#include "rocksdb/db.h"
 #include "db/memtable.h"
-#include "leveldb/env.h"
-#include "leveldb/iterator.h"
+#include "rocksdb/env.h"
+#include "rocksdb/iterator.h"
 #include "util/coding.h"

-namespace leveldb {
+namespace rocksdb {

 class InternalKeyComparator;
 class Mutex;
@@ -21,17 +23,15 @@ using std::list;

 // Increase reference count on all underling memtables
 void MemTableList::RefAll() {
-  for (list<MemTable*>::iterator it = memlist_.begin();
-       it != memlist_.end() ; ++it) {
-    (*it)->Ref();
+  for (auto &memtable : memlist_) {
+    memtable->Ref();
  }
 }

 // Drop reference count on all underling memtables
 void MemTableList::UnrefAll() {
-  for (list<MemTable*>::iterator it = memlist_.begin();
-       it != memlist_.end() ; ++it) {
-    (*it)->Unref();
+  for (auto &memtable : memlist_) {
+    memtable->Unref();
  }
 }

@@ -44,7 +44,8 @@ int MemTableList::size() {
 // Returns true if there is at least one memtable on which flush has
 // not yet started.
 bool MemTableList::IsFlushPending(int min_write_buffer_number_to_merge) {
-  if (num_flush_not_started_ >= min_write_buffer_number_to_merge) {
+  if ((flush_requested_ && num_flush_not_started_ >= 1) ||
+      (num_flush_not_started_ >= min_write_buffer_number_to_merge)) {
    assert(imm_flush_needed.NoBarrier_Load() != nullptr);
    return true;
  }
@@ -53,8 +54,7 @@ bool MemTableList::IsFlushPending(int min_write_buffer_number_to_merge) {

 // Returns the memtables that need to be flushed.
 void MemTableList::PickMemtablesToFlush(std::vector<MemTable*>* ret) {
-  for (list<MemTable*>::reverse_iterator it = memlist_.rbegin();
-       it != memlist_.rend(); it++) {
+  for (auto it = memlist_.rbegin(); it != memlist_.rend(); it++) {
    MemTable* m = *it;
    if (!m->flush_in_progress_) {
      assert(!m->flush_completed_);
@@ -66,6 +66,7 @@ void MemTableList::PickMemtablesToFlush(std::vector<MemTable*>* ret) {
      ret->push_back(m);
    }
  }
+  flush_requested_ = false; // start-flush request is complete
 }

 // Record a successful flush in the manifest file
@@ -95,15 +96,12 @@ Status MemTableList::InstallMemtableFlushResults(
  }

  // flush was sucessful
-  bool first = true;
-  for (MemTable* m : mems) {
-
+  for (size_t i = 0; i < mems.size(); ++i) {
    // All the edits are associated with the first memtable of this batch.
-    assert(first || m->GetEdits()->NumEntries() == 0);
-    first = false;
+    assert(i == 0 || mems[i]->GetEdits()->NumEntries() == 0);

-    m->flush_completed_ = true;
-    m->file_number_ = file_number;
+    mems[i]->flush_completed_ = true;
+    mems[i]->file_number_ = file_number;
  }

  // if some other thread is already commiting, then return
@@ -123,22 +121,21 @@ Status MemTableList::InstallMemtableFlushResults(
    if (!m->flush_completed_) {
      break;
    }
-    first = true;

-    Log(info_log,
-        "Level-0 commit table #%llu: started",
-        (unsigned long long)m->file_number_);
+    Log(info_log, "Level-0 commit table #%lu started", m->file_number_);

    // this can release and reacquire the mutex.
    s = vset->LogAndApply(&m->edit_, mu);

    // All the later memtables that have the same filenum
    // are part of the same batch. They can be committed now.
+    uint64_t mem_id = 1;  // how many memtables has been flushed.
    do {
      if (s.ok()) { // commit new state
-        Log(info_log, "Level-0 commit table #%llu: done %s",
-                       (unsigned long long)m->file_number_,
-                       first ? "": "bulk");
+        Log(info_log,
+            "Level-0 commit table #%lu: memtable #%lu done",
+            m->file_number_,
+            mem_id);
        memlist_.remove(m);
        assert(m->file_number_ > 0);

@@ -151,8 +148,10 @@ Status MemTableList::InstallMemtableFlushResults(
        size_--;
      } else {
        //commit failed. setup state so that we can flush again.
-        Log(info_log, "Level-0 commit table #%llu: failed",
-                       (unsigned long long)m->file_number_);
+        Log(info_log,
+            "Level-0 commit table #%lu: memtable #%lu failed",
+            m->file_number_,
+            mem_id);
        m->flush_completed_ = false;
        m->flush_in_progress_ = false;
        m->edit_.Clear();
@@ -162,7 +161,7 @@ Status MemTableList::InstallMemtableFlushResults(
        imm_flush_needed.Release_Store((void *)1);
        s = Status::IOError("Unable to commit flushed memtable");
      }
-      first = false;
+      ++mem_id;
    } while (!memlist_.empty() && (m = memlist_.back()) &&
             m->file_number_ == file_number);
  }
@@ -175,6 +174,7 @@ void MemTableList::Add(MemTable* m) {
  assert(size_ >= num_flush_not_started_);
  size_++;
  memlist_.push_front(m);
+  m->MarkImmutable();
  num_flush_not_started_++;
  if (num_flush_not_started_ == 1) {
    imm_flush_needed.Release_Store((void *)1);
@@ -184,9 +184,8 @@ void MemTableList::Add(MemTable* m) {
 // Returns an estimate of the number of bytes of data in use.
 size_t MemTableList::ApproximateMemoryUsage() {
  size_t size = 0;
-  for (list<MemTable*>::iterator it = memlist_.begin();
-       it != memlist_.end(); ++it) {
-    size += (*it)->ApproximateMemoryUsage();
+  for (auto &memtable : memlist_) {
+    size += memtable->ApproximateMemoryUsage();
  }
  return size;
 }
@@ -197,9 +196,8 @@ size_t MemTableList::ApproximateMemoryUsage() {
 bool MemTableList::Get(const LookupKey& key, std::string* value, Status* s,
                       std::deque<std::string>* operands,
                       const Options& options) {
-  for (list<MemTable*>::iterator it = memlist_.begin();
-       it != memlist_.end(); ++it) {
-    if ((*it)->Get(key, value, s, operands, options)) {
+  for (auto &memtable : memlist_) {
+    if (memtable->Get(key, value, s, operands, options)) {
      return true;
    }
  }
@@ -207,10 +205,9 @@ bool MemTableList::Get(const LookupKey& key, std::string* value, Status* s,
 }

 void MemTableList::GetMemTables(std::vector<MemTable*>* output) {
-  for (list<MemTable*>::iterator it = memlist_.begin();
-       it != memlist_.end(); ++it) {
-    output->push_back(*it);
+  for (auto &memtable : memlist_) {
+    output->push_back(memtable);
  }
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,17 +1,19 @@
-// Copyright (c) 2012 Facebook.
-
-#ifndef STORAGE_LEVELDB_DB_MEMTABLELIST_H_
-#define STORAGE_LEVELDB_DB_MEMTABLELIST_H_
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//

+#pragma once
 #include <string>
 #include <list>
 #include <deque>
-#include "leveldb/db.h"
+#include "rocksdb/db.h"
 #include "db/dbformat.h"
 #include "db/skiplist.h"
 #include "memtable.h"

-namespace leveldb {
+namespace rocksdb {

 class InternalKeyComparator;
 class Mutex;
@@ -29,7 +31,8 @@ class MemTableList {
 public:
  // A list of memtables.
  MemTableList() : size_(0), num_flush_not_started_(0),
-    commit_in_progress_(false) {
+    commit_in_progress_(false),
+    flush_requested_(false) {
    imm_flush_needed.Release_Store(nullptr);
  }
  ~MemTableList() {};
@@ -51,7 +54,8 @@ class MemTableList {
  // not yet started.
  bool IsFlushPending(int min_write_buffer_number_to_merge);

-  // Returns the earliest memtables that needs to be flushed.
+  // Returns the earliest memtables that needs to be flushed. The returned
+  // memtables are guaranteed to be in the ascending order of created time.
  void PickMemtablesToFlush(std::vector<MemTable*>* mems);

  // Commit a successful flush in the manifest file
@@ -76,6 +80,9 @@ class MemTableList {
  // Returns the list of underlying memtables.
  void GetMemTables(std::vector<MemTable*>* list);

+  // Request a flush of all existing memtables to storage
+  void FlushRequested() { flush_requested_ = true; }
+
  // Copying allowed
  // MemTableList(const MemTableList&);
  // void operator=(const MemTableList&);
@@ -90,8 +97,9 @@ class MemTableList {
  // committing in progress
  bool commit_in_progress_;

+  // Requested a flush of all memtables to storage
+  bool flush_requested_;
+
 };

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_MEMTABLELIST_H_
+}  // namespace rocksdb
@@ -1,12 +1,17 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #include "merge_helper.h"
 #include "db/dbformat.h"
-#include "leveldb/comparator.h"
-#include "leveldb/db.h"
-#include "leveldb/merge_operator.h"
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/merge_operator.h"
 #include <string>
 #include <stdio.h>

-namespace leveldb {
+namespace rocksdb {

 // PRE:  iter points to the first merge type entry
 // POST: iter points to the first entry beyond the merge process (or the end)
@@ -15,7 +20,7 @@ namespace leveldb {
 //       operands_ stores the list of merge operands encountered while merging.
 //       keys_[i] corresponds to operands_[i] for each i.
 void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
-                             bool at_bottom) {
+                             bool at_bottom, shared_ptr<Statistics> stats) {
  // Get a copy of the internal key, before it's invalidated by iter->Next()
  // Also maintain the list of merge operands seen.
  keys_.clear();
@@ -67,9 +72,9 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
      //   => store result in operands_.back() (and update keys_.back())
      //   => change the entry type to kTypeValue for keys_.back()
      // We are done! Return a success if the merge passes.
-      success_ = user_merge_operator_->Merge(ikey.user_key, nullptr,
-                                             operands_, &merge_result,
-                                             logger_);
+      success_ = user_merge_operator_->FullMerge(ikey.user_key, nullptr,
+                                                 operands_, &merge_result,
+                                                 logger_);

      // We store the result in keys_.back() and operands_.back()
      // if nothing went wrong (i.e.: no operand corruption on disk)
@@ -79,6 +84,8 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
        UpdateInternalKey(&key[0], key.size(),
                          orig_ikey.sequence, orig_ikey.type);
        swap(operands_.back(), merge_result);
+      } else {
+        RecordTick(stats, NUMBER_MERGE_FAILURES);
      }

      // move iter to the next entry (before doing anything else)
@@ -93,9 +100,9 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
      //   => change the entry type to kTypeValue for keys_.back()
      // We are done! Success!
      const Slice value = iter->value();
-      success_ = user_merge_operator_->Merge(ikey.user_key, &value,
-                                             operands_, &merge_result,
-                                             logger_);
+      success_ = user_merge_operator_->FullMerge(ikey.user_key, &value,
+                                                 operands_, &merge_result,
+                                                 logger_);

      // We store the result in keys_.back() and operands_.back()
      // if nothing went wrong (i.e.: no operand corruption on disk)
@@ -105,6 +112,8 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
        UpdateInternalKey(&key[0], key.size(),
                          orig_ikey.sequence, orig_ikey.type);
        swap(operands_.back(), merge_result);
+      } else {
+        RecordTick(stats, NUMBER_MERGE_FAILURES);
      }

      // move iter to the next entry
@@ -166,9 +175,9 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
    assert(kTypeMerge == orig_ikey.type);
    assert(operands_.size() >= 1);
    assert(operands_.size() == keys_.size());
-    success_ = user_merge_operator_->Merge(ikey.user_key, nullptr,
-                                           operands_, &merge_result,
-                                           logger_);
+    success_ = user_merge_operator_->FullMerge(ikey.user_key, nullptr,
+                                               operands_, &merge_result,
+                                               logger_);

    if (success_) {
      std::string& key = keys_.back();  // The original key encountered
@@ -179,9 +188,10 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
      // The final value() is always stored in operands_.back()
      swap(operands_.back(),merge_result);
    } else {
+      RecordTick(stats, NUMBER_MERGE_FAILURES);
      // Do nothing if not success_. Leave keys() and operands() as they are.
    }
  }
 }

-} // namespace leveldb
+} // namespace rocksdb
@@ -1,12 +1,18 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #ifndef MERGE_HELPER_H
 #define MERGE_HELPER_H

 #include "db/dbformat.h"
-#include "leveldb/slice.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/statistics.h"
 #include <string>
 #include <deque>

-namespace leveldb {
+namespace rocksdb {

 class Comparator;
 class Iterator;
@@ -40,7 +46,7 @@ class MergeHelper {
  // at_bottom:   (IN) true if the iterator covers the bottem level, which means
  //                   we could reach the start of the history of this user key.
  void MergeUntil(Iterator* iter, SequenceNumber stop_before = 0,
-                  bool at_bottom = false);
+                  bool at_bottom = false, shared_ptr<Statistics> stats=nullptr);

  // Query the merge result
  // These are valid until the next MergeUntil call
@@ -92,6 +98,6 @@ class MergeHelper {
  bool success_;
 };

-} // namespace leveldb
+} // namespace rocksdb

 #endif
@@ -1,18 +1,20 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 /**
 * Back-end implementation details specific to the Merge Operator.
- *
- * @author Deon Nicholas (dnicholas@fb.com)
- * Copyright 2013 Facebook
 */

-#include "leveldb/merge_operator.h"
+#include "rocksdb/merge_operator.h"

-namespace leveldb {
+namespace rocksdb {

 // Given a "real" merge from the library, call the user's
 // associative merge function one-by-one on each of the operands.
 // NOTE: It is assumed that the client's merge-operator will handle any errors.
-bool AssociativeMergeOperator::Merge(
+bool AssociativeMergeOperator::FullMerge(
    const Slice& key,
    const Slice* existing_value,
    const std::deque<std::string>& operand_list,
@@ -48,4 +50,4 @@ bool AssociativeMergeOperator::PartialMerge(
  return Merge(key, &left_operand, right_operand, new_value, logger);
 }

-} // namespace leveldb
+} // namespace rocksdb
@@ -1,12 +1,17 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #include <assert.h>
 #include <memory>
 #include <iostream>

-#include "leveldb/cache.h"
-#include "leveldb/comparator.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
-#include "leveldb/merge_operator.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/merge_operator.h"
 #include "db/dbformat.h"
 #include "db/db_impl.h"
 #include "utilities/merge_operators.h"
@@ -14,16 +19,15 @@
 #include "utilities/utility_db.h"

 using namespace std;
-using namespace leveldb;
+using namespace rocksdb;

-auto mergeOperator = MergeOperators::CreateUInt64AddOperator();

 std::shared_ptr<DB> OpenDb(const string& dbname, const bool ttl = false) {
  DB* db;
  StackableDB* sdb;
  Options options;
  options.create_if_missing = true;
-  options.merge_operator = mergeOperator.get();
+  options.merge_operator = MergeOperators::CreateUInt64AddOperator();
  Status s;
  DestroyDB(dbname, Options());
  if (ttl) {
@@ -86,7 +90,7 @@ class Counters {
    }
  }

-  // mapped to a leveldb Delete
+  // mapped to a rocksdb Delete
  bool remove(const string& key) {
    auto s = db_->Delete(delete_option_, key);

@@ -98,7 +102,7 @@ class Counters {
    }
  }

-  // mapped to a leveldb Get
+  // mapped to a rocksdb Get
  bool get(const string& key, uint64_t *value) {
    string str;
    auto s = db_->Get(get_option_, key, &str);
@@ -160,7 +164,7 @@ class MergeBasedCounters : public Counters {
        merge_option_() {
  }

-  // mapped to a leveldb Merge operation
+  // mapped to a rocksdb Merge operation
  virtual bool add(const string& key, uint64_t value) override {
    char encoded[sizeof(uint64_t)];
    EncodeFixed64(encoded, value);
@@ -0,0 +1,328 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+#include <algorithm>
+#include <iostream>
+#include <vector>
+#include "/usr/include/valgrind/callgrind.h"
+
+#include "rocksdb/db.h"
+#include "rocksdb/perf_context.h"
+#include "util/histogram.h"
+#include "util/stop_watch.h"
+#include "util/testharness.h"
+
+
+bool FLAGS_random_key = false;
+bool FLAGS_use_set_based_memetable = false;
+int FLAGS_total_keys = 100;
+int FLAGS_write_buffer_size = 1000000000;
+int FLAGS_max_write_buffer_number = 8;
+int FLAGS_min_write_buffer_number_to_merge = 7;
+
+// Path to the database on file system
+const std::string kDbName = rocksdb::test::TmpDir() + "/perf_context_test";
+
+namespace rocksdb {
+
+std::shared_ptr<DB> OpenDb() {
+    DB* db;
+    Options options;
+    options.create_if_missing = true;
+    options.write_buffer_size = FLAGS_write_buffer_size;
+    options.max_write_buffer_number = FLAGS_max_write_buffer_number;
+    options.min_write_buffer_number_to_merge =
+      FLAGS_min_write_buffer_number_to_merge;
+
+    if (FLAGS_use_set_based_memetable) {
+      auto prefix_extractor = rocksdb::NewFixedPrefixTransform(0);
+      options.memtable_factory =
+        std::make_shared<rocksdb::PrefixHashRepFactory>(prefix_extractor);
+    }
+
+    Status s = DB::Open(options, kDbName,  &db);
+    ASSERT_OK(s);
+    return std::shared_ptr<DB>(db);
+}
+
+class PerfContextTest { };
+
+TEST(PerfContextTest, SeekIntoDeletion) {
+  DestroyDB(kDbName, Options());
+  auto db = OpenDb();
+  WriteOptions write_options;
+  ReadOptions read_options;
+
+  for (int i = 0; i < FLAGS_total_keys; ++i) {
+    std::string key = "k" + std::to_string(i);
+    std::string value = "v" + std::to_string(i);
+
+    db->Put(write_options, key, value);
+  }
+
+  for (int i = 0; i < FLAGS_total_keys -1 ; ++i) {
+    std::string key = "k" + std::to_string(i);
+    db->Delete(write_options, key);
+  }
+
+  HistogramImpl hist_get;
+  HistogramImpl hist_get_time;
+  for (int i = 0; i < FLAGS_total_keys - 1; ++i) {
+    std::string key = "k" + std::to_string(i);
+    std::string value;
+
+    perf_context.Reset();
+    StopWatchNano timer(Env::Default(), true);
+    auto status = db->Get(read_options, key, &value);
+    auto elapsed_nanos = timer.ElapsedNanos();
+    ASSERT_TRUE(status.IsNotFound());
+    hist_get.Add(perf_context.user_key_comparison_count);
+    hist_get_time.Add(elapsed_nanos);
+  }
+
+  std::cout << "Get uesr key comparison: \n" << hist_get.ToString()
+            << "Get time: \n" << hist_get_time.ToString();
+
+  HistogramImpl hist_seek_to_first;
+  std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+
+  perf_context.Reset();
+  StopWatchNano timer(Env::Default(), true);
+  iter->SeekToFirst();
+  hist_seek_to_first.Add(perf_context.user_key_comparison_count);
+  auto elapsed_nanos = timer.ElapsedNanos();
+
+  std::cout << "SeekToFirst uesr key comparison: \n" << hist_seek_to_first.ToString()
+            << "ikey skipped: " << perf_context.internal_key_skipped_count << "\n"
+            << "idelete skipped: " << perf_context.internal_delete_skipped_count << "\n"
+            << "elapsed: " << elapsed_nanos << "\n";
+
+  HistogramImpl hist_seek;
+  for (int i = 0; i < FLAGS_total_keys; ++i) {
+    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+    std::string key = "k" + std::to_string(i);
+
+    perf_context.Reset();
+    StopWatchNano timer(Env::Default(), true);
+    iter->Seek(key);
+    auto elapsed_nanos = timer.ElapsedNanos();
+    hist_seek.Add(perf_context.user_key_comparison_count);
+    std::cout << "seek cmp: " << perf_context.user_key_comparison_count
+              << " ikey skipped " << perf_context.internal_key_skipped_count
+              << " idelete skipped " << perf_context.internal_delete_skipped_count
+              << " elapsed: " << elapsed_nanos << "ns\n";
+
+    perf_context.Reset();
+    ASSERT_TRUE(iter->Valid());
+    StopWatchNano timer2(Env::Default(), true);
+    iter->Next();
+    auto elapsed_nanos2 = timer2.ElapsedNanos();
+    std::cout << "next cmp: " << perf_context.user_key_comparison_count
+              << "elapsed: " << elapsed_nanos2 << "ns\n";
+  }
+
+  std::cout << "Seek uesr key comparison: \n" << hist_seek.ToString();
+}
+
+TEST(PerfContextTest, StopWatchNanoOverhead) {
+  // profile the timer cost by itself!
+  const int kTotalIterations = 1000000;
+  std::vector<uint64_t> timings(kTotalIterations);
+
+  StopWatchNano timer(Env::Default(), true);
+  for (auto& timing : timings) {
+    timing = timer.ElapsedNanos(true /* reset */);
+  }
+
+  HistogramImpl histogram;
+  for (const auto timing : timings) {
+    histogram.Add(timing);
+  }
+
+  std::cout << histogram.ToString();
+}
+
+TEST(PerfContextTest, StopWatchOverhead) {
+  // profile the timer cost by itself!
+  const int kTotalIterations = 1000000;
+  std::vector<uint64_t> timings(kTotalIterations);
+
+  StopWatch timer(Env::Default());
+  for (auto& timing : timings) {
+    timing = timer.ElapsedMicros();
+  }
+
+  HistogramImpl histogram;
+  uint64_t prev_timing = 0;
+  for (const auto timing : timings) {
+    histogram.Add(timing - prev_timing);
+    prev_timing = timing;
+  }
+
+  std::cout << histogram.ToString();
+}
+
+void ProfileKeyComparison() {
+  DestroyDB(kDbName, Options());    // Start this test with a fresh DB
+
+  auto db = OpenDb();
+
+  WriteOptions write_options;
+  ReadOptions read_options;
+
+  HistogramImpl hist_put;
+  HistogramImpl hist_get;
+
+  std::cout << "Inserting " << FLAGS_total_keys << " key/value pairs\n...\n";
+
+  std::vector<int> keys;
+  for (int i = 0; i < FLAGS_total_keys; ++i) {
+    keys.push_back(i);
+  }
+
+  if (FLAGS_random_key) {
+    std::random_shuffle(keys.begin(), keys.end());
+  }
+
+  for (const int i : keys) {
+    std::string key = "k" + std::to_string(i);
+    std::string value = "v" + std::to_string(i);
+
+    perf_context.Reset();
+    db->Put(write_options, key, value);
+    hist_put.Add(perf_context.user_key_comparison_count);
+
+    perf_context.Reset();
+    db->Get(read_options, key, &value);
+    hist_get.Add(perf_context.user_key_comparison_count);
+  }
+
+  std::cout << "Put uesr key comparison: \n" << hist_put.ToString()
+            << "Get uesr key comparison: \n" << hist_get.ToString();
+
+}
+
+TEST(PerfContextTest, KeyComparisonCount) {
+  SetPerfLevel(kEnableCount);
+  ProfileKeyComparison();
+
+  SetPerfLevel(kDisable);
+  ProfileKeyComparison();
+
+  SetPerfLevel(kEnableTime);
+  ProfileKeyComparison();
+}
+
+// make perf_context_test
+// export ROCKSDB_TESTS=PerfContextTest.SeekKeyComparison
+// For one memtable:
+// ./perf_context_test --write_buffer_size=500000 --total_keys=10000
+// For two memtables:
+// ./perf_context_test --write_buffer_size=250000 --total_keys=10000
+// Specify --random_key=1 to shuffle the key before insertion
+// Results show that, for sequential insertion, worst-case Seek Key comparison
+// is close to the total number of keys (linear), when there is only one
+// memtable. When there are two memtables, even the avg Seek Key comparison
+// starts to become linear to the input size.
+
+TEST(PerfContextTest, SeekKeyComparison) {
+  DestroyDB(kDbName, Options());
+  auto db = OpenDb();
+  WriteOptions write_options;
+  ReadOptions read_options;
+
+  std::cout << "Inserting " << FLAGS_total_keys << " key/value pairs\n...\n";
+
+  std::vector<int> keys;
+  for (int i = 0; i < FLAGS_total_keys; ++i) {
+    keys.push_back(i);
+  }
+
+  if (FLAGS_random_key) {
+    std::random_shuffle(keys.begin(), keys.end());
+  }
+
+  HistogramImpl hist_put_time;
+  HistogramImpl hist_wal_time;
+  HistogramImpl hist_time_diff;
+
+  SetPerfLevel(kEnableTime);
+  StopWatchNano timer(Env::Default());
+  for (const int i : keys) {
+    std::string key = "k" + std::to_string(i);
+    std::string value = "v" + std::to_string(i);
+
+    perf_context.Reset();
+    timer.Start();
+    db->Put(write_options, key, value);
+    auto put_time = timer.ElapsedNanos();
+    hist_put_time.Add(put_time);
+    hist_wal_time.Add(perf_context.wal_write_time);
+    hist_time_diff.Add(put_time - perf_context.wal_write_time);
+  }
+
+  std::cout << "Put time:\n" << hist_put_time.ToString()
+            << "WAL time:\n" << hist_wal_time.ToString()
+            << "time diff:\n" << hist_time_diff.ToString();
+
+  HistogramImpl hist_seek;
+  HistogramImpl hist_next;
+
+  for (int i = 0; i < FLAGS_total_keys; ++i) {
+    std::string key = "k" + std::to_string(i);
+    std::string value = "v" + std::to_string(i);
+
+    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+    perf_context.Reset();
+    iter->Seek(key);
+    ASSERT_TRUE(iter->Valid());
+    ASSERT_EQ(iter->value().ToString(), value);
+    hist_seek.Add(perf_context.user_key_comparison_count);
+  }
+
+  std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+  for (iter->SeekToFirst(); iter->Valid();) {
+    perf_context.Reset();
+    iter->Next();
+    hist_next.Add(perf_context.user_key_comparison_count);
+  }
+
+  std::cout << "Seek:\n" << hist_seek.ToString()
+            << "Next:\n" << hist_next.ToString();
+}
+
+}
+
+int main(int argc, char** argv) {
+
+  for (int i = 1; i < argc; i++) {
+    int n;
+    char junk;
+
+    if (sscanf(argv[i], "--write_buffer_size=%d%c", &n, &junk) == 1) {
+      FLAGS_write_buffer_size = n;
+    }
+
+    if (sscanf(argv[i], "--total_keys=%d%c", &n, &junk) == 1) {
+      FLAGS_total_keys = n;
+    }
+
+    if (sscanf(argv[i], "--random_key=%d%c", &n, &junk) == 1 &&
+        (n == 0 || n == 1)) {
+      FLAGS_random_key = n;
+    }
+
+    if (sscanf(argv[i], "--use_set_based_memetable=%d%c", &n, &junk) == 1 &&
+        (n == 0 || n == 1)) {
+      FLAGS_use_set_based_memetable = n;
+    }
+
+  }
+
+  std::cout << kDbName << "\n";
+
+  rocksdb::test::RunAllTests();
+  return 0;
+}
@@ -0,0 +1,73 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Wrap an underlying iterator, but exclude any results not starting
+// with a given prefix.  Seeking to keys not beginning with the prefix
+// is invalid, and SeekToLast is not implemented (that would be
+// non-trivial), but otherwise this iterator will behave just like the
+// underlying iterator would if there happened to be no non-matching
+// keys in the dataset.
+
+#pragma once
+#include "rocksdb/iterator.h"
+
+namespace rocksdb {
+
+class PrefixFilterIterator : public Iterator {
+ private:
+  Iterator* iter_;
+  const Slice &prefix_;
+  const SliceTransform *prefix_extractor_;
+  Status status_;
+
+ public:
+  PrefixFilterIterator(Iterator* iter,
+                       const Slice &prefix,
+                       const SliceTransform* prefix_extractor)
+                             : iter_(iter), prefix_(prefix),
+                               prefix_extractor_(prefix_extractor),
+                               status_(Status::OK()) {
+    if (prefix_extractor == nullptr) {
+      status_ = Status::InvalidArgument("A prefix filter may not be used "
+                                        "unless a function is also defined "
+                                        "for extracting prefixes");
+    } else if (!prefix_extractor_->InRange(prefix)) {
+      status_ = Status::InvalidArgument("Must provide a slice for prefix which"
+                                        "is a prefix for some key");
+    }
+  }
+  ~PrefixFilterIterator() {
+    delete iter_;
+  }
+  Slice key() const { return iter_->key(); }
+  Slice value() const { return iter_->value(); }
+  Status status() const {
+    if (!status_.ok()) {
+      return status_;
+    }
+    return iter_->status();
+  }
+  void Next() { iter_->Next(); }
+  void Prev() { iter_->Prev(); }
+  void Seek(const Slice& k) {
+    if (prefix_extractor_->Transform(k) == prefix_) {
+      iter_->Seek(k);
+    } else {
+      status_ = Status::InvalidArgument("Seek must begin with target prefix");
+    }
+  }
+  void SeekToFirst() {
+    Seek(prefix_);
+  }
+  void SeekToLast() {
+    status_ = Status::NotSupported("SeekToLast is incompatible with prefixes");
+  }
+  bool Valid() const {
+    return (status_.ok() && iter_->Valid() &&
+            prefix_extractor_->Transform(iter_->key()) == prefix_);
+  }
+};
+
+}  // namespace rocksdb
@@ -0,0 +1,320 @@
+#include <algorithm>
+#include <iostream>
+#include <vector>
+
+#include <gflags/gflags.h>
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/perf_context.h"
+#include "util/histogram.h"
+#include "util/stop_watch.h"
+#include "util/testharness.h"
+
+DEFINE_bool(use_prefix_hash_memtable, true, "");
+DEFINE_bool(use_nolock_version, true, "");
+DEFINE_bool(trigger_deadlock, false,
+            "issue delete in range scan to trigger PrefixHashMap deadlock");
+DEFINE_uint64(bucket_count, 100000, "number of buckets");
+DEFINE_uint64(num_locks, 10001, "number of locks");
+DEFINE_bool(random_prefix, false, "randomize prefix");
+DEFINE_uint64(total_prefixes, 1000, "total number of prefixes");
+DEFINE_uint64(items_per_prefix, 10, "total number of values per prefix");
+DEFINE_int64(write_buffer_size, 1000000000, "");
+DEFINE_int64(max_write_buffer_number, 8, "");
+DEFINE_int64(min_write_buffer_number_to_merge, 7, "");
+
+// Path to the database on file system
+const std::string kDbName = rocksdb::test::TmpDir() + "/prefix_test";
+
+namespace rocksdb {
+
+struct TestKey {
+  uint64_t prefix;
+  uint64_t sorted;
+
+  TestKey(uint64_t prefix, uint64_t sorted) : prefix(prefix), sorted(sorted) {}
+};
+
+// return a slice backed by test_key
+inline Slice TestKeyToSlice(const TestKey& test_key) {
+  return Slice((const char*)&test_key, sizeof(test_key));
+}
+
+inline const TestKey* SliceToTestKey(const Slice& slice) {
+  assert(slice.size() == sizeof(TestKey));
+  return (const TestKey*)slice.data();
+}
+
+class TestKeyComparator : public Comparator {
+ public:
+  virtual int Compare(const Slice& a, const Slice& b) const {
+    const TestKey* key_a = SliceToTestKey(a);
+    const TestKey* key_b = SliceToTestKey(b);
+    if (key_a->prefix != key_b->prefix) {
+      if (key_a->prefix < key_b->prefix) return -1;
+      if (key_a->prefix > key_b->prefix) return 1;
+      assert(false);
+    } else {
+      if (key_a->sorted < key_b->sorted) return -1;
+      if (key_a->sorted > key_b->sorted) return 1;
+      if (key_a->sorted == key_b->sorted) return 0;
+      assert(false);
+    }
+    assert(false);
+    return 0;
+  }
+
+  virtual const char* Name() const override {
+    return "TestKeyComparator";
+  }
+
+  virtual void FindShortestSeparator(
+      std::string* start,
+      const Slice& limit) const {
+  }
+
+  virtual void FindShortSuccessor(std::string* key) const {}
+
+};
+
+class PrefixTest {
+ public:
+  std::shared_ptr<DB> OpenDb() {
+    DB* db;
+
+    options.create_if_missing = true;
+    options.write_buffer_size = FLAGS_write_buffer_size;
+    options.max_write_buffer_number = FLAGS_max_write_buffer_number;
+    options.min_write_buffer_number_to_merge =
+      FLAGS_min_write_buffer_number_to_merge;
+
+    options.comparator = new TestKeyComparator();
+    if (FLAGS_use_prefix_hash_memtable) {
+      auto prefix_extractor = NewFixedPrefixTransform(8);
+      options.prefix_extractor = prefix_extractor;
+      if (FLAGS_use_nolock_version) {
+        options.memtable_factory =
+          std::make_shared<rocksdb::PrefixHashRepNoLockFactory>(
+            prefix_extractor, FLAGS_bucket_count);
+      } else {
+        options.memtable_factory =
+          std::make_shared<rocksdb::PrefixHashRepFactory>(
+            prefix_extractor, FLAGS_bucket_count, FLAGS_num_locks);
+      }
+    }
+
+    Status s = DB::Open(options, kDbName,  &db);
+    ASSERT_OK(s);
+    return std::shared_ptr<DB>(db);
+  }
+  ~PrefixTest() {
+    delete options.comparator;
+  }
+ protected:
+  Options options;
+};
+
+TEST(PrefixTest, DynamicPrefixIterator) {
+
+  DestroyDB(kDbName, Options());
+  auto db = OpenDb();
+  WriteOptions write_options;
+  ReadOptions read_options;
+
+  std::vector<uint64_t> prefixes;
+  for (uint64_t i = 0; i < FLAGS_total_prefixes; ++i) {
+    prefixes.push_back(i);
+  }
+
+  if (FLAGS_random_prefix) {
+    std::random_shuffle(prefixes.begin(), prefixes.end());
+  }
+
+  // insert x random prefix, each with y continuous element.
+  for (auto prefix : prefixes) {
+     for (uint64_t sorted = 0; sorted < FLAGS_items_per_prefix; sorted++) {
+      TestKey test_key(prefix, sorted);
+
+      Slice key = TestKeyToSlice(test_key);
+      std::string value = "v" + std::to_string(sorted);
+
+      ASSERT_OK(db->Put(write_options, key, value));
+    }
+  }
+
+  // test seek existing keys
+  HistogramImpl hist_seek_time;
+  HistogramImpl hist_seek_comparison;
+
+  if (FLAGS_use_prefix_hash_memtable) {
+    read_options.prefix_seek = true;
+  }
+  std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+
+  for (auto prefix : prefixes) {
+    TestKey test_key(prefix, FLAGS_items_per_prefix / 2);
+    Slice key = TestKeyToSlice(test_key);
+    std::string value = "v" + std::to_string(0);
+
+    perf_context.Reset();
+    StopWatchNano timer(Env::Default(), true);
+    uint64_t total_keys = 0;
+    for (iter->Seek(key); iter->Valid(); iter->Next()) {
+      if (FLAGS_trigger_deadlock) {
+        std::cout << "Behold the deadlock!\n";
+        db->Delete(write_options, iter->key());
+      }
+      auto test_key = SliceToTestKey(iter->key());
+      if (test_key->prefix != prefix) break;
+      total_keys++;
+    }
+    hist_seek_time.Add(timer.ElapsedNanos());
+    hist_seek_comparison.Add(perf_context.user_key_comparison_count);
+    ASSERT_EQ(total_keys, FLAGS_items_per_prefix - FLAGS_items_per_prefix/2);
+  }
+
+  std::cout << "Seek key comparison: \n"
+            << hist_seek_comparison.ToString()
+            << "Seek time: \n"
+            << hist_seek_time.ToString();
+
+  // test non-existing keys
+  HistogramImpl hist_no_seek_time;
+  HistogramImpl hist_no_seek_comparison;
+
+  for (auto prefix = FLAGS_total_prefixes;
+       prefix < FLAGS_total_prefixes + 100;
+       prefix++) {
+    TestKey test_key(prefix, 0);
+    Slice key = TestKeyToSlice(test_key);
+
+    perf_context.Reset();
+    StopWatchNano timer(Env::Default(), true);
+    iter->Seek(key);
+    hist_no_seek_time.Add(timer.ElapsedNanos());
+    hist_no_seek_comparison.Add(perf_context.user_key_comparison_count);
+    ASSERT_TRUE(!iter->Valid());
+  }
+
+  std::cout << "non-existing Seek key comparison: \n"
+            << hist_no_seek_comparison.ToString()
+            << "non-existing Seek time: \n"
+            << hist_no_seek_time.ToString();
+}
+
+TEST(PrefixTest, PrefixHash) {
+
+  DestroyDB(kDbName, Options());
+  auto db = OpenDb();
+  WriteOptions write_options;
+  ReadOptions read_options;
+
+  std::vector<uint64_t> prefixes;
+  for (uint64_t i = 0; i < FLAGS_total_prefixes; ++i) {
+    prefixes.push_back(i);
+  }
+
+  if (FLAGS_random_prefix) {
+    std::random_shuffle(prefixes.begin(), prefixes.end());
+  }
+
+  // insert x random prefix, each with y continuous element.
+  HistogramImpl hist_put_time;
+  HistogramImpl hist_put_comparison;
+
+  for (auto prefix : prefixes) {
+     for (uint64_t sorted = 0; sorted < FLAGS_items_per_prefix; sorted++) {
+      TestKey test_key(prefix, sorted);
+
+      Slice key = TestKeyToSlice(test_key);
+      std::string value = "v" + std::to_string(sorted);
+
+      perf_context.Reset();
+      StopWatchNano timer(Env::Default(), true);
+      ASSERT_OK(db->Put(write_options, key, value));
+      hist_put_time.Add(timer.ElapsedNanos());
+      hist_put_comparison.Add(perf_context.user_key_comparison_count);
+    }
+  }
+
+  std::cout << "Put key comparison: \n" << hist_put_comparison.ToString()
+            << "Put time: \n" << hist_put_time.ToString();
+
+
+  // test seek existing keys
+  HistogramImpl hist_seek_time;
+  HistogramImpl hist_seek_comparison;
+
+  for (auto prefix : prefixes) {
+    TestKey test_key(prefix, 0);
+    Slice key = TestKeyToSlice(test_key);
+    std::string value = "v" + std::to_string(0);
+
+    Slice key_prefix;
+    if (FLAGS_use_prefix_hash_memtable) {
+      key_prefix = options.prefix_extractor->Transform(key);
+      read_options.prefix = &key_prefix;
+    }
+    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+
+    perf_context.Reset();
+    StopWatchNano timer(Env::Default(), true);
+    uint64_t total_keys = 0;
+    for (iter->Seek(key); iter->Valid(); iter->Next()) {
+      if (FLAGS_trigger_deadlock) {
+        std::cout << "Behold the deadlock!\n";
+        db->Delete(write_options, iter->key());
+      }
+      auto test_key = SliceToTestKey(iter->key());
+      if (test_key->prefix != prefix) break;
+      total_keys++;
+    }
+    hist_seek_time.Add(timer.ElapsedNanos());
+    hist_seek_comparison.Add(perf_context.user_key_comparison_count);
+    ASSERT_EQ(total_keys, FLAGS_items_per_prefix);
+  }
+
+  std::cout << "Seek key comparison: \n"
+            << hist_seek_comparison.ToString()
+            << "Seek time: \n"
+            << hist_seek_time.ToString();
+
+  // test non-existing keys
+  HistogramImpl hist_no_seek_time;
+  HistogramImpl hist_no_seek_comparison;
+
+  for (auto prefix = FLAGS_total_prefixes;
+       prefix < FLAGS_total_prefixes + 100;
+       prefix++) {
+    TestKey test_key(prefix, 0);
+    Slice key = TestKeyToSlice(test_key);
+
+    if (FLAGS_use_prefix_hash_memtable) {
+      Slice key_prefix = options.prefix_extractor->Transform(key);
+      read_options.prefix = &key_prefix;
+    }
+    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+
+    perf_context.Reset();
+    StopWatchNano timer(Env::Default(), true);
+    iter->Seek(key);
+    hist_no_seek_time.Add(timer.ElapsedNanos());
+    hist_no_seek_comparison.Add(perf_context.user_key_comparison_count);
+    ASSERT_TRUE(!iter->Valid());
+  }
+
+  std::cout << "non-existing Seek key comparison: \n"
+            << hist_no_seek_comparison.ToString()
+            << "non-existing Seek time: \n"
+            << hist_no_seek_time.ToString();
+}
+
+}
+
+int main(int argc, char** argv) {
+  google::ParseCommandLineFlags(&argc, &argv, true);
+  std::cout << kDbName << "\n";
+
+  rocksdb::test::RunAllTests();
+  return 0;
+}
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -34,11 +39,11 @@
 #include "db/table_cache.h"
 #include "db/version_edit.h"
 #include "db/write_batch_internal.h"
-#include "leveldb/comparator.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"

-namespace leveldb {
+namespace rocksdb {

 namespace {

@@ -74,7 +79,7 @@ class Repairer {
        bytes += tables_[i].meta.file_size;
      }
      Log(options_.info_log,
-          "**** Repaired leveldb %s; "
+          "**** Repaired rocksdb %s; "
          "recovered %d files; %llu bytes. "
          "Some data may have been lost. "
          "****",
@@ -88,6 +93,7 @@ class Repairer {
 private:
  struct TableInfo {
    FileMetaData meta;
+    SequenceNumber min_sequence;
    SequenceNumber max_sequence;
  };

@@ -202,7 +208,7 @@ class Repairer {
        continue;
      }
      WriteBatchInternal::SetContents(&batch, record);
-      status = WriteBatchInternal::InsertInto(&batch, mem);
+      status = WriteBatchInternal::InsertInto(&batch, mem, &options_);
      if (status.ok()) {
        counter += WriteBatchInternal::Count(&batch);
      } else {
@@ -220,7 +226,7 @@ class Repairer {
    Iterator* iter = mem->NewIterator();
    status = BuildTable(dbname_, env_, options_, storage_options_,
                        table_cache_, iter, &meta,
-                        icmp_.user_comparator(), 0, 0);
+                        icmp_.user_comparator(), 0, 0, true);
    delete iter;
    mem->Unref();
    mem = nullptr;
@@ -264,6 +270,7 @@ class Repairer {
          ReadOptions(), storage_options_, t->meta.number, t->meta.file_size);
      bool empty = true;
      ParsedInternalKey parsed;
+      t->min_sequence = 0;
      t->max_sequence = 0;
      for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
        Slice key = iter->key();
@@ -280,6 +287,9 @@ class Repairer {
          t->meta.smallest.DecodeFrom(key);
        }
        t->meta.largest.DecodeFrom(key);
+        if (parsed.sequence < t->min_sequence) {
+          t->min_sequence = parsed.sequence;
+        }
        if (parsed.sequence > t->max_sequence) {
          t->max_sequence = parsed.sequence;
        }
@@ -320,7 +330,8 @@ class Repairer {
      // TODO(opt): separate out into multiple levels
      const TableInfo& t = tables_[i];
      edit_->AddFile(0, t.meta.number, t.meta.file_size,
-                    t.meta.smallest, t.meta.largest);
+                    t.meta.smallest, t.meta.largest,
+                    t.min_sequence, t.max_sequence);
    }

    //fprintf(stderr, "NewDescriptor:\n%s\n", edit_.DebugString().c_str());
@@ -377,4 +388,4 @@ Status RepairDB(const std::string& dbname, const Options& options) {
  return repairer.Run();
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -0,0 +1,793 @@
+// 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.
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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 <algorithm>
+#include <set>
+
+#include "rocksdb/db.h"
+#include "rocksdb/filter_policy.h"
+#include "db/db_impl.h"
+#include "db/filename.h"
+#include "db/version_set.h"
+#include "db/write_batch_internal.h"
+#include "db/db_statistics.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/compaction_filter.h"
+#include "rocksdb/env.h"
+#include "rocksdb/table.h"
+#include "util/hash.h"
+#include "util/logging.h"
+#include "util/mutexlock.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+#include "utilities/merge_operators.h"
+
+using std::unique_ptr;
+
+namespace rocksdb {
+
+// SimpleTable is a simple table format for UNIT TEST ONLY. It is not built
+// as production quality.
+// SimpleTable requires the input key size to be fixed 16 bytes, value cannot
+// be longer than 150000 bytes and stored data on disk in this format:
+// +--------------------------------------------+  <= key1 offset
+// | key1            | value_size (4 bytes) |   |
+// +----------------------------------------+   |
+// | value1                                     |
+// |                                            |
+// +----------------------------------------+---+  <= key2 offset
+// | key2            | value_size (4 bytes) |   |
+// +----------------------------------------+   |
+// | value2                                     |
+// |                                            |
+// |        ......                              |
+// +-----------------+--------------------------+   <= index_block_offset
+// | key1            | key1 offset (8 bytes)    |
+// +-----------------+--------------------------+
+// | key2            | key2 offset (8 bytes)    |
+// +-----------------+--------------------------+
+// | key3            | key3 offset (8 bytes)    |
+// +-----------------+--------------------------+
+// |        ......                              |
+// +-----------------+------------+-------------+
+// | index_block_offset (8 bytes) |
+// +------------------------------+
+
+// SimpleTable is a simple table format for UNIT TEST ONLY. It is not built
+// as production quality.
+class SimpleTableReader: public TableReader {
+public:
+  // Attempt to open the table that is stored in bytes [0..file_size)
+  // of "file", and read the metadata entries necessary to allow
+  // retrieving data from the table.
+  //
+  // If successful, returns ok and sets "*table" to the newly opened
+  // table.  The client should delete "*table" when no longer needed.
+  // If there was an error while initializing the table, sets "*table"
+  // to nullptr and returns a non-ok status.  Does not take ownership of
+  // "*source", but the client must ensure that "source" remains live
+  // for the duration of the returned table's lifetime.
+  //
+  // *file must remain live while this Table is in use.
+  static Status Open(const Options& options, const EnvOptions& soptions,
+                     unique_ptr<RandomAccessFile> && file, uint64_t file_size,
+                     unique_ptr<TableReader>* table_reader);
+
+  bool PrefixMayMatch(const Slice& internal_prefix) override;
+
+  Iterator* NewIterator(const ReadOptions&) override;
+
+  Status Get(
+      const ReadOptions&, const Slice& key, void* arg,
+      bool (*handle_result)(void* arg, const Slice& k, const Slice& v, bool),
+      void (*mark_key_may_exist)(void*) = nullptr) override;
+
+  uint64_t ApproximateOffsetOf(const Slice& key) override;
+
+  bool TEST_KeyInCache(const ReadOptions& options, const Slice& key) override;
+
+  void SetupForCompaction() override;
+
+  TableStats& GetTableStats() override;
+
+  ~SimpleTableReader();
+
+private:
+  struct Rep;
+  Rep* rep_;
+
+  explicit SimpleTableReader(Rep* rep) {
+    rep_ = rep;
+  }
+  friend class TableCache;
+  friend class SimpleTableIterator;
+
+  Status GetOffset(const Slice& target, uint64_t* offset);
+
+  // No copying allowed
+  explicit SimpleTableReader(const TableReader&) = delete;
+  void operator=(const TableReader&) = delete;
+};
+
+// Iterator to iterate SimpleTable
+class SimpleTableIterator: public Iterator {
+public:
+  explicit SimpleTableIterator(SimpleTableReader* table);
+  ~SimpleTableIterator();
+
+  bool Valid() const;
+
+  void SeekToFirst();
+
+  void SeekToLast();
+
+  void Seek(const Slice& target);
+
+  void Next();
+
+  void Prev();
+
+  Slice key() const;
+
+  Slice value() const;
+
+  Status status() const;
+
+private:
+  SimpleTableReader* table_;
+  uint64_t offset_;
+  uint64_t next_offset_;
+  Slice key_;
+  Slice value_;
+  char tmp_str_[4];
+  char* key_str_;
+  char* value_str_;
+  int value_str_len_;
+  Status status_;
+  // No copying allowed
+  SimpleTableIterator(const SimpleTableIterator&) = delete;
+  void operator=(const Iterator&) = delete;
+};
+
+struct SimpleTableReader::Rep {
+  ~Rep() {
+  }
+  Rep(const EnvOptions& storage_options, uint64_t index_start_offset,
+      int num_entries) :
+      soptions(storage_options), index_start_offset(index_start_offset),
+      num_entries(num_entries) {
+  }
+
+  Options options;
+  const EnvOptions& soptions;
+  Status status;
+  unique_ptr<RandomAccessFile> file;
+  uint64_t index_start_offset;
+  int num_entries;
+  TableStats table_stats;
+
+  const static int user_key_size = 16;
+  const static int offset_length = 8;
+  const static int key_footer_len = 8;
+
+  static int GetInternalKeyLength() {
+    return user_key_size + key_footer_len;
+  }
+};
+
+SimpleTableReader::~SimpleTableReader() {
+  delete rep_;
+}
+
+Status SimpleTableReader::Open(const Options& options,
+                               const EnvOptions& soptions,
+                               unique_ptr<RandomAccessFile> && file,
+                               uint64_t size,
+                               unique_ptr<TableReader>* table_reader) {
+  char footer_space[Rep::offset_length];
+  Slice footer_input;
+  Status s = file->Read(size - Rep::offset_length, Rep::offset_length,
+                        &footer_input, footer_space);
+  if (s.ok()) {
+    uint64_t index_start_offset = DecodeFixed64(footer_space);
+
+    int num_entries = (size - Rep::offset_length - index_start_offset)
+        / (Rep::GetInternalKeyLength() + Rep::offset_length);
+    SimpleTableReader::Rep* rep = new SimpleTableReader::Rep(soptions,
+                                                             index_start_offset,
+                                                             num_entries);
+
+    rep->file = std::move(file);
+    rep->options = options;
+    table_reader->reset(new SimpleTableReader(rep));
+  }
+  return s;
+}
+
+void SimpleTableReader::SetupForCompaction() {
+}
+
+TableStats& SimpleTableReader::GetTableStats() {
+  return rep_->table_stats;
+}
+
+bool SimpleTableReader::PrefixMayMatch(const Slice& internal_prefix) {
+  return true;
+}
+
+Iterator* SimpleTableReader::NewIterator(const ReadOptions& options) {
+  return new SimpleTableIterator(this);
+}
+
+Status SimpleTableReader::GetOffset(const Slice& target, uint64_t* offset) {
+  uint32_t left = 0;
+  uint32_t right = rep_->num_entries - 1;
+  char key_chars[Rep::GetInternalKeyLength()];
+  Slice tmp_slice;
+
+  uint32_t target_offset = 0;
+  while (left <= right) {
+    uint32_t mid = (left + right + 1) / 2;
+
+    uint64_t offset_to_read = rep_->index_start_offset
+        + (Rep::GetInternalKeyLength() + Rep::offset_length) * mid;
+    Status s = rep_->file->Read(offset_to_read, Rep::GetInternalKeyLength(),
+                                &tmp_slice, key_chars);
+    if (!s.ok()) {
+      return s;
+    }
+
+    int compare_result = rep_->options.comparator->Compare(tmp_slice, target);
+
+    if (compare_result < 0) {
+      if (left == right) {
+        target_offset = right + 1;
+        break;
+      }
+      left = mid;
+    } else {
+      if (left == right) {
+        target_offset = left;
+        break;
+      }
+      right = mid - 1;
+    }
+  }
+
+  if (target_offset >= (uint32_t) rep_->num_entries) {
+    *offset = rep_->index_start_offset;
+    return Status::OK();
+  }
+
+  char value_offset_chars[Rep::offset_length];
+
+  int64_t offset_for_value_offset = rep_->index_start_offset
+      + (Rep::GetInternalKeyLength() + Rep::offset_length) * target_offset
+      + Rep::GetInternalKeyLength();
+  Status s = rep_->file->Read(offset_for_value_offset, Rep::offset_length,
+                              &tmp_slice, value_offset_chars);
+  if (s.ok()) {
+    *offset = DecodeFixed64(value_offset_chars);
+  }
+  return s;
+}
+
+Status SimpleTableReader::Get(
+    const ReadOptions& options, const Slice& k, void* arg,
+    bool (*saver)(void*, const Slice&, const Slice&, bool),
+    void (*mark_key_may_exist)(void*)) {
+  Status s;
+  SimpleTableIterator* iter = new SimpleTableIterator(this);
+  for (iter->Seek(k); iter->Valid(); iter->Next()) {
+    if (!(*saver)(arg, iter->key(), iter->value(), true)) {
+      break;
+    }
+  }
+  s = iter->status();
+  delete iter;
+  return s;
+}
+
+bool SimpleTableReader::TEST_KeyInCache(const ReadOptions& options,
+                                        const Slice& key) {
+  return false;
+}
+
+uint64_t SimpleTableReader::ApproximateOffsetOf(const Slice& key) {
+  return 0;
+}
+
+SimpleTableIterator::SimpleTableIterator(SimpleTableReader* table) :
+    table_(table) {
+  key_str_ = new char[SimpleTableReader::Rep::GetInternalKeyLength()];
+  value_str_len_ = -1;
+  SeekToFirst();
+}
+
+SimpleTableIterator::~SimpleTableIterator() {
+ delete[] key_str_;
+ if (value_str_len_ >= 0) {
+   delete[] value_str_;
+ }
+}
+
+bool SimpleTableIterator::Valid() const {
+  return offset_ < table_->rep_->index_start_offset && offset_ >= 0;
+}
+
+void SimpleTableIterator::SeekToFirst() {
+  next_offset_ = 0;
+  Next();
+}
+
+void SimpleTableIterator::SeekToLast() {
+  assert(false);
+}
+
+void SimpleTableIterator::Seek(const Slice& target) {
+  Status s = table_->GetOffset(target, &next_offset_);
+  if (!s.ok()) {
+    status_ = s;
+  }
+  Next();
+}
+
+void SimpleTableIterator::Next() {
+  offset_ = next_offset_;
+  if (offset_ >= table_->rep_->index_start_offset) {
+    return;
+  }
+  Slice result;
+  int internal_key_size = SimpleTableReader::Rep::GetInternalKeyLength();
+
+  Status s = table_->rep_->file->Read(next_offset_, internal_key_size, &result,
+                                      key_str_);
+  next_offset_ += internal_key_size;
+  key_ = result;
+
+  Slice value_size_slice;
+  s = table_->rep_->file->Read(next_offset_, 4, &value_size_slice, tmp_str_);
+  next_offset_ += 4;
+  uint32_t value_size = DecodeFixed32(tmp_str_);
+
+  Slice value_slice;
+  if ((int) value_size > value_str_len_) {
+    if (value_str_len_ >= 0) {
+      delete[] value_str_;
+    }
+    value_str_ = new char[value_size];
+    value_str_len_ = value_size;
+  }
+  s = table_->rep_->file->Read(next_offset_, value_size, &value_slice,
+                               value_str_);
+  next_offset_ += value_size;
+  value_ = value_slice;
+}
+
+void SimpleTableIterator::Prev() {
+  assert(false);
+}
+
+Slice SimpleTableIterator::key() const {
+  Log(table_->rep_->options.info_log, "key!!!!");
+  return key_;
+}
+
+Slice SimpleTableIterator::value() const {
+  return value_;
+}
+
+Status SimpleTableIterator::status() const {
+  return status_;
+}
+
+class SimpleTableBuilder: public TableBuilder {
+public:
+  // Create a builder that will store the contents of the table it is
+  // building in *file.  Does not close the file.  It is up to the
+  // caller to close the file after calling Finish(). The output file
+  // will be part of level specified by 'level'.  A value of -1 means
+  // that the caller does not know which level the output file will reside.
+  SimpleTableBuilder(const Options& options, WritableFile* file,
+                     CompressionType compression_type);
+
+  // REQUIRES: Either Finish() or Abandon() has been called.
+  ~SimpleTableBuilder();
+
+  // Add key,value to the table being constructed.
+  // REQUIRES: key is after any previously added key according to comparator.
+  // REQUIRES: Finish(), Abandon() have not been called
+  void Add(const Slice& key, const Slice& value) override;
+
+  // Return non-ok iff some error has been detected.
+  Status status() const override;
+
+  // Finish building the table.  Stops using the file passed to the
+  // constructor after this function returns.
+  // REQUIRES: Finish(), Abandon() have not been called
+  Status Finish() override;
+
+  // Indicate that the contents of this builder should be abandoned.  Stops
+  // using the file passed to the constructor after this function returns.
+  // If the caller is not going to call Finish(), it must call Abandon()
+  // before destroying this builder.
+  // REQUIRES: Finish(), Abandon() have not been called
+  void Abandon() override;
+
+  // Number of calls to Add() so far.
+  uint64_t NumEntries() const override;
+
+  // Size of the file generated so far.  If invoked after a successful
+  // Finish() call, returns the size of the final generated file.
+  uint64_t FileSize() const override;
+
+private:
+  struct Rep;
+  Rep* rep_;
+
+  // No copying allowed
+  SimpleTableBuilder(const SimpleTableBuilder&) = delete;
+  void operator=(const SimpleTableBuilder&) = delete;
+};
+
+struct SimpleTableBuilder::Rep {
+  Options options;
+  WritableFile* file;
+  uint64_t offset = 0;
+  Status status;
+
+  uint64_t num_entries = 0;
+
+  bool closed = false;  // Either Finish() or Abandon() has been called.
+
+  const static int user_key_size = 16;
+  const static int offset_length = 8;
+  const static int key_footer_len = 8;
+
+  static int GetInternalKeyLength() {
+    return user_key_size + key_footer_len;
+  }
+
+  std::string index;
+
+  Rep(const Options& opt, WritableFile* f) :
+      options(opt), file(f) {
+  }
+  ~Rep() {
+  }
+};
+
+SimpleTableBuilder::SimpleTableBuilder(const Options& options,
+                                       WritableFile* file,
+                                       CompressionType compression_type) :
+    rep_(new SimpleTableBuilder::Rep(options, file)) {
+}
+
+SimpleTableBuilder::~SimpleTableBuilder() {
+  delete (rep_);
+}
+
+void SimpleTableBuilder::Add(const Slice& key, const Slice& value) {
+  assert((int ) key.size() == Rep::GetInternalKeyLength());
+
+  // Update index
+  rep_->index.append(key.data(), key.size());
+  PutFixed64(&(rep_->index), rep_->offset);
+
+  // Write key-value pair
+  rep_->file->Append(key);
+  rep_->offset += Rep::GetInternalKeyLength();
+
+  std::string size;
+  int value_size = value.size();
+  PutFixed32(&size, value_size);
+  Slice sizeSlice(size);
+  rep_->file->Append(sizeSlice);
+  rep_->file->Append(value);
+  rep_->offset += value_size + 4;
+
+  rep_->num_entries++;
+}
+
+Status SimpleTableBuilder::status() const {
+  return Status::OK();
+}
+
+Status SimpleTableBuilder::Finish() {
+  Rep* r = rep_;
+  assert(!r->closed);
+  r->closed = true;
+
+  uint64_t index_offset = rep_->offset;
+  Slice index_slice(rep_->index);
+  rep_->file->Append(index_slice);
+  rep_->offset += index_slice.size();
+
+  std::string index_offset_str;
+  PutFixed64(&index_offset_str, index_offset);
+  Slice foot_slice(index_offset_str);
+  rep_->file->Append(foot_slice);
+  rep_->offset += foot_slice.size();
+
+  return Status::OK();
+}
+
+void SimpleTableBuilder::Abandon() {
+  rep_->closed = true;
+}
+
+uint64_t SimpleTableBuilder::NumEntries() const {
+  return rep_->num_entries;
+}
+
+uint64_t SimpleTableBuilder::FileSize() const {
+  return rep_->offset;
+}
+
+class SimpleTableFactory: public TableFactory {
+public:
+  ~SimpleTableFactory() {
+  }
+  SimpleTableFactory() {
+  }
+  const char* Name() const override {
+    return "SimpleTable";
+  }
+  Status GetTableReader(const Options& options, const EnvOptions& soptions,
+                        unique_ptr<RandomAccessFile> && file,
+                        uint64_t file_size,
+                        unique_ptr<TableReader>* table_reader) const;
+
+  TableBuilder* GetTableBuilder(const Options& options, WritableFile* file,
+                                CompressionType compression_type) const;
+};
+
+Status SimpleTableFactory::GetTableReader(
+    const Options& options, const EnvOptions& soptions,
+    unique_ptr<RandomAccessFile> && file, uint64_t file_size,
+    unique_ptr<TableReader>* table_reader) const {
+
+  return SimpleTableReader::Open(options, soptions, std::move(file), file_size,
+                                 table_reader);
+}
+
+TableBuilder* SimpleTableFactory::GetTableBuilder(
+    const Options& options, WritableFile* file,
+    CompressionType compression_type) const {
+  return new SimpleTableBuilder(options, file, compression_type);
+}
+
+class SimpleTableDBTest {
+protected:
+public:
+  std::string dbname_;
+  Env* env_;
+  DB* db_;
+
+  Options last_options_;
+
+  SimpleTableDBTest() :
+      env_(Env::Default()) {
+    dbname_ = test::TmpDir() + "/simple_table_db_test";
+    ASSERT_OK(DestroyDB(dbname_, Options()));
+    db_ = nullptr;
+    Reopen();
+  }
+
+  ~SimpleTableDBTest() {
+    delete db_;
+    ASSERT_OK(DestroyDB(dbname_, Options()));
+  }
+
+  // Return the current option configuration.
+  Options CurrentOptions() {
+    Options options;
+    options.table_factory.reset(new SimpleTableFactory());
+    return options;
+  }
+
+  DBImpl* dbfull() {
+    return reinterpret_cast<DBImpl*>(db_);
+  }
+
+  void Reopen(Options* options = nullptr) {
+    ASSERT_OK(TryReopen(options));
+  }
+
+  void Close() {
+    delete db_;
+    db_ = nullptr;
+  }
+
+  void DestroyAndReopen(Options* options = nullptr) {
+    //Destroy using last options
+    Destroy(&last_options_);
+    ASSERT_OK(TryReopen(options));
+  }
+
+  void Destroy(Options* options) {
+    delete db_;
+    db_ = nullptr;
+    ASSERT_OK(DestroyDB(dbname_, *options));
+  }
+
+  Status PureReopen(Options* options, DB** db) {
+    return DB::Open(*options, dbname_, db);
+  }
+
+  Status TryReopen(Options* options = nullptr) {
+    delete db_;
+    db_ = nullptr;
+    Options opts;
+    if (options != nullptr) {
+      opts = *options;
+    } else {
+      opts = CurrentOptions();
+      opts.create_if_missing = true;
+    }
+    last_options_ = opts;
+
+    return DB::Open(opts, dbname_, &db_);
+  }
+
+  Status Put(const Slice& k, const Slice& v) {
+    return db_->Put(WriteOptions(), k, v);
+  }
+
+  Status Delete(const std::string& k) {
+    return db_->Delete(WriteOptions(), k);
+  }
+
+  std::string Get(const std::string& k, const Snapshot* snapshot = nullptr) {
+    ReadOptions options;
+    options.snapshot = snapshot;
+    std::string result;
+    Status s = db_->Get(options, k, &result);
+    if (s.IsNotFound()) {
+      result = "NOT_FOUND";
+    } else if (!s.ok()) {
+      result = s.ToString();
+    }
+    return result;
+  }
+
+
+  int NumTableFilesAtLevel(int level) {
+    std::string property;
+    ASSERT_TRUE(
+        db_->GetProperty("rocksdb.num-files-at-level" + NumberToString(level),
+                         &property));
+    return atoi(property.c_str());
+  }
+
+  // Return spread of files per level
+  std::string FilesPerLevel() {
+    std::string result;
+    int last_non_zero_offset = 0;
+    for (int level = 0; level < db_->NumberLevels(); level++) {
+      int f = NumTableFilesAtLevel(level);
+      char buf[100];
+      snprintf(buf, sizeof(buf), "%s%d", (level ? "," : ""), f);
+      result += buf;
+      if (f > 0) {
+        last_non_zero_offset = result.size();
+      }
+    }
+    result.resize(last_non_zero_offset);
+    return result;
+  }
+
+  std::string IterStatus(Iterator* iter) {
+    std::string result;
+    if (iter->Valid()) {
+      result = iter->key().ToString() + "->" + iter->value().ToString();
+    } else {
+      result = "(invalid)";
+    }
+    return result;
+  }
+};
+
+TEST(SimpleTableDBTest, Empty) {
+  ASSERT_TRUE(db_ != nullptr);
+  ASSERT_EQ("NOT_FOUND", Get("0000000000000foo"));
+}
+
+TEST(SimpleTableDBTest, ReadWrite) {
+  ASSERT_OK(Put("0000000000000foo", "v1"));
+  ASSERT_EQ("v1", Get("0000000000000foo"));
+  ASSERT_OK(Put("0000000000000bar", "v2"));
+  ASSERT_OK(Put("0000000000000foo", "v3"));
+  ASSERT_EQ("v3", Get("0000000000000foo"));
+  ASSERT_EQ("v2", Get("0000000000000bar"));
+}
+
+TEST(SimpleTableDBTest, Flush) {
+  ASSERT_OK(Put("0000000000000foo", "v1"));
+  ASSERT_OK(Put("0000000000000bar", "v2"));
+  ASSERT_OK(Put("0000000000000foo", "v3"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v3", Get("0000000000000foo"));
+  ASSERT_EQ("v2", Get("0000000000000bar"));
+}
+
+TEST(SimpleTableDBTest, Flush2) {
+  ASSERT_OK(Put("0000000000000bar", "b"));
+  ASSERT_OK(Put("0000000000000foo", "v1"));
+  dbfull()->TEST_FlushMemTable();
+
+  ASSERT_OK(Put("0000000000000foo", "v2"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v2", Get("0000000000000foo"));
+
+  ASSERT_OK(Put("0000000000000eee", "v3"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v3", Get("0000000000000eee"));
+
+  ASSERT_OK(Delete("0000000000000bar"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("NOT_FOUND", Get("0000000000000bar"));
+
+  ASSERT_OK(Put("0000000000000eee", "v5"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v5", Get("0000000000000eee"));
+}
+
+static std::string Key(int i) {
+  char buf[100];
+  snprintf(buf, sizeof(buf), "key_______%06d", i);
+  return std::string(buf);
+}
+
+static std::string RandomString(Random* rnd, int len) {
+  std::string r;
+  test::RandomString(rnd, len, &r);
+  return r;
+}
+
+TEST(SimpleTableDBTest, CompactionTrigger) {
+  Options options = CurrentOptions();
+  options.write_buffer_size = 100 << 10; //100KB
+  options.num_levels = 3;
+  options.max_mem_compaction_level = 0;
+  options.level0_file_num_compaction_trigger = 3;
+  Reopen(&options);
+
+  Random rnd(301);
+
+  for (int num = 0; num < options.level0_file_num_compaction_trigger - 1;
+      num++) {
+    std::vector<std::string> values;
+    // Write 120KB (12 values, each 10K)
+    for (int i = 0; i < 12; i++) {
+      values.push_back(RandomString(&rnd, 10000));
+      ASSERT_OK(Put(Key(i), values[i]));
+    }
+    dbfull()->TEST_WaitForFlushMemTable();
+    ASSERT_EQ(NumTableFilesAtLevel(0), num + 1);
+  }
+
+  //generate one more file in level-0, and should trigger level-0 compaction
+  std::vector<std::string> values;
+  for (int i = 0; i < 12; i++) {
+    values.push_back(RandomString(&rnd, 10000));
+    ASSERT_OK(Put(Key(i), values[i]));
+  }
+  dbfull()->TEST_WaitForCompact();
+
+  ASSERT_EQ(NumTableFilesAtLevel(0), 0);
+  ASSERT_EQ(NumTableFilesAtLevel(1), 1);
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -25,15 +30,13 @@
 // ... prev vs. next pointer ordering ...
 //

-#ifndef STORAGE_LEVELDB_DB_SKIPLIST_H_
-#define STORAGE_LEVELDB_DB_SKIPLIST_H_
-
+#pragma once
 #include <assert.h>
 #include <stdlib.h>
 #include "port/port.h"
 #include "util/random.h"

-namespace leveldb {
+namespace rocksdb {

 template<typename Key, class Comparator>
 class SkipList {
@@ -107,6 +110,7 @@ class SkipList {

  // Used for optimizing sequential insert patterns
  Node* prev_[kMaxHeight];
+  int   prev_height_;

  inline int GetMaxHeight() const {
    return static_cast<int>(
@@ -267,6 +271,10 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOr
    Node* x = prev[0];
    Node* next = x->Next(0);
    if ((x == head_) || KeyIsAfterNode(key, x)) {
+      // Adjust all relevant insertion points to the previous entry
+      for (int i = 1; i < prev_height_; i++) {
+        prev[i] = x;
+      }
      return next;
    }
  }
@@ -275,6 +283,9 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOr
  int level = GetMaxHeight() - 1;
  while (true) {
    Node* next = x->Next(level);
+    // Make sure the lists are sorted.
+    // If x points to head_ or next points nullptr, it is trivially satisfied.
+    assert((x == head_) || (next == nullptr) || KeyIsAfterNode(next->key, x));
    if (KeyIsAfterNode(key, next)) {
      // Keep searching in this list
      x = next;
@@ -337,6 +348,7 @@ SkipList<Key,Comparator>::SkipList(Comparator cmp, Arena* arena)
      arena_(arena),
      head_(NewNode(0 /* any key will do */, kMaxHeight)),
      max_height_(reinterpret_cast<void*>(1)),
+      prev_height_(1),
      rnd_(0xdeadbeef) {
  for (int i = 0; i < kMaxHeight; i++) {
    head_->SetNext(i, nullptr);
@@ -378,6 +390,7 @@ void SkipList<Key,Comparator>::Insert(const Key& key) {
    prev_[i]->SetNext(i, x);
  }
  prev_[0] = x;
+  prev_height_ = height;
 }

 template<typename Key, class Comparator>
@@ -390,6 +403,4 @@ bool SkipList<Key,Comparator>::Contains(const Key& key) const {
  }
 }

-}  // namespace leveldb
-
-#endif // STORAGE_LEVELDB_DB_SKIPLIST_H_
+}  // namespace rocksdb
@@ -1,16 +1,21 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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/skiplist.h"
 #include <set>
-#include "leveldb/env.h"
+#include "rocksdb/env.h"
 #include "util/arena_impl.h"
 #include "util/hash.h"
 #include "util/random.h"
 #include "util/testharness.h"

-namespace leveldb {
+namespace rocksdb {

 typedef uint64_t Key;

@@ -371,8 +376,8 @@ TEST(SkipTest, Concurrent3) { RunConcurrent(3); }
 TEST(SkipTest, Concurrent4) { RunConcurrent(4); }
 TEST(SkipTest, Concurrent5) { RunConcurrent(5); }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,13 +1,16 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_SNAPSHOT_H_
-#define STORAGE_LEVELDB_DB_SNAPSHOT_H_
+#pragma once
+#include "rocksdb/db.h"

-#include "leveldb/db.h"
-
-namespace leveldb {
+namespace rocksdb {

 class SnapshotList;

@@ -80,6 +83,4 @@ class SnapshotList {
  SnapshotImpl list_;
 };

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_SNAPSHOT_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -6,16 +11,16 @@

 #include "db/filename.h"

-#include "leveldb/statistics.h"
-#include "table/table.h"
+#include "rocksdb/statistics.h"
+#include "rocksdb/table.h"
 #include "util/coding.h"
 #include "util/stop_watch.h"

-namespace leveldb {
+namespace rocksdb {

 static void DeleteEntry(const Slice& key, void* value) {
-  Table* table = reinterpret_cast<Table*>(value);
-  delete table;
+  TableReader* table_reader = reinterpret_cast<TableReader*>(value);
+  delete table_reader;
 }

 static void UnrefEntry(void* arg1, void* arg2) {
@@ -32,7 +37,10 @@ TableCache::TableCache(const std::string& dbname,
      dbname_(dbname),
      options_(options),
      storage_options_(storage_options),
-      cache_(NewLRUCache(entries, options->table_cache_numshardbits)) {}
+      cache_(
+        NewLRUCache(entries, options->table_cache_numshardbits,
+                    options->table_cache_remove_scan_count_limit)) {
+}

 TableCache::~TableCache() {
 }
@@ -48,14 +56,14 @@ Status TableCache::FindTable(const EnvOptions& toptions,
  *handle = cache_->Lookup(key);
  if (*handle == nullptr) {
    if (no_io) { // Dont do IO and return a not-found status
-      return Status::NotFound("Table not found in table_cache, no_io is set");
+      return Status::Incomplete("Table not found in table_cache, no_io is set");
    }
    if (table_io != nullptr) {
      *table_io = true;    // we had to do IO from storage
    }
    std::string fname = TableFileName(dbname_, file_number);
    unique_ptr<RandomAccessFile> file;
-    unique_ptr<Table> table;
+    unique_ptr<TableReader> table_reader;
    s = env_->NewRandomAccessFile(fname, &file, toptions);
    RecordTick(options_->statistics, NO_FILE_OPENS);
    if (s.ok()) {
@@ -63,17 +71,19 @@ Status TableCache::FindTable(const EnvOptions& toptions,
        file->Hint(RandomAccessFile::RANDOM);
      }
      StopWatch sw(env_, options_->statistics, TABLE_OPEN_IO_MICROS);
-      s = Table::Open(*options_, toptions, std::move(file), file_size, &table);
+      s = options_->table_factory->GetTableReader(*options_, toptions,
+                                                  std::move(file), file_size,
+                                                  &table_reader);
    }

    if (!s.ok()) {
-      assert(table == nullptr);
+      assert(table_reader == nullptr);
      RecordTick(options_->statistics, NO_FILE_ERRORS);
      // We do not cache error results so that if the error is transient,
      // or somebody repairs the file, we recover automatically.
    } else {
      assert(file.get() == nullptr);
-      *handle = cache_->Insert(key, table.release(), 1, &DeleteEntry);
+      *handle = cache_->Insert(key, table_reader.release(), 1, &DeleteEntry);
    }
  }
  return s;
@@ -83,28 +93,29 @@ Iterator* TableCache::NewIterator(const ReadOptions& options,
                                  const EnvOptions& toptions,
                                  uint64_t file_number,
                                  uint64_t file_size,
-                                  Table** tableptr,
+                                  TableReader** table_reader_ptr,
                                  bool for_compaction) {
-  if (tableptr != nullptr) {
-    *tableptr = nullptr;
+  if (table_reader_ptr != nullptr) {
+    *table_reader_ptr = nullptr;
  }

  Cache::Handle* handle = nullptr;
-  Status s = FindTable(toptions, file_number, file_size, &handle);
+  Status s = FindTable(toptions, file_number, file_size, &handle,
+                       nullptr, options.read_tier == kBlockCacheTier);
  if (!s.ok()) {
    return NewErrorIterator(s);
  }

-  Table* table =
-    reinterpret_cast<Table*>(cache_->Value(handle));
-  Iterator* result = table->NewIterator(options);
+  TableReader* table_reader =
+    reinterpret_cast<TableReader*>(cache_->Value(handle));
+  Iterator* result = table_reader->NewIterator(options);
  result->RegisterCleanup(&UnrefEntry, cache_.get(), handle);
-  if (tableptr != nullptr) {
-    *tableptr = table;
+  if (table_reader_ptr != nullptr) {
+    *table_reader_ptr = table_reader;
  }

  if (for_compaction) {
-    table->SetupForCompaction();
+    table_reader->SetupForCompaction();
  }

  return result;
@@ -117,17 +128,17 @@ Status TableCache::Get(const ReadOptions& options,
                       void* arg,
                       bool (*saver)(void*, const Slice&, const Slice&, bool),
                       bool* table_io,
-                       void (*mark_key_may_exist)(void*),
-                       const bool no_io) {
+                       void (*mark_key_may_exist)(void*)) {
  Cache::Handle* handle = nullptr;
  Status s = FindTable(storage_options_, file_number, file_size,
-                       &handle, table_io, no_io);
+                       &handle, table_io,
+                       options.read_tier == kBlockCacheTier);
  if (s.ok()) {
-    Table* t =
-      reinterpret_cast<Table*>(cache_->Value(handle));
-    s = t->InternalGet(options, k, arg, saver, mark_key_may_exist, no_io);
+    TableReader* t =
+      reinterpret_cast<TableReader*>(cache_->Value(handle));
+    s = t->Get(options, k, arg, saver, mark_key_may_exist);
    cache_->Release(handle);
-  } else if (no_io && s.IsNotFound()) {
+  } else if (options.read_tier && s.IsIncomplete()) {
    // Couldnt find Table in cache but treat as kFound if no_io set
    (*mark_key_may_exist)(arg);
    return Status::OK();
@@ -135,10 +146,28 @@ Status TableCache::Get(const ReadOptions& options,
  return s;
 }

+bool TableCache::PrefixMayMatch(const ReadOptions& options,
+                                uint64_t file_number,
+                                uint64_t file_size,
+                                const Slice& internal_prefix,
+                                bool* table_io) {
+  Cache::Handle* handle = nullptr;
+  Status s = FindTable(storage_options_, file_number,
+                       file_size, &handle, table_io);
+  bool may_match = true;
+  if (s.ok()) {
+    TableReader* t =
+      reinterpret_cast<TableReader*>(cache_->Value(handle));
+    may_match = t->PrefixMayMatch(internal_prefix);
+    cache_->Release(handle);
+  }
+  return may_match;
+}
+
 void TableCache::Evict(uint64_t file_number) {
  char buf[sizeof(file_number)];
  EncodeFixed64(buf, file_number);
  cache_->Erase(Slice(buf, sizeof(buf)));
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,21 +1,24 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
 //
 // Thread-safe (provides internal synchronization)

-#ifndef STORAGE_LEVELDB_DB_TABLE_CACHE_H_
-#define STORAGE_LEVELDB_DB_TABLE_CACHE_H_
-
+#pragma once
 #include <string>
 #include <stdint.h>
 #include "db/dbformat.h"
-#include "leveldb/env.h"
-#include "leveldb/cache.h"
+#include "rocksdb/env.h"
+#include "rocksdb/cache.h"
 #include "port/port.h"
-#include "table/table.h"
+#include "rocksdb/table.h"

-namespace leveldb {
+namespace rocksdb {

 class Env;

@@ -36,7 +39,7 @@ class TableCache {
                        const EnvOptions& toptions,
                        uint64_t file_number,
                        uint64_t file_size,
-                        Table** tableptr = nullptr,
+                        TableReader** table_reader_ptr = nullptr,
                        bool for_compaction = false);

  // If a seek to internal key "k" in specified file finds an entry,
@@ -49,8 +52,13 @@ class TableCache {
             void* arg,
             bool (*handle_result)(void*, const Slice&, const Slice&, bool),
             bool* table_io,
-             void (*mark_key_may_exist)(void*) = nullptr,
-             const bool no_io = false);
+             void (*mark_key_may_exist)(void*) = nullptr);
+
+  // Determine whether the table may contain the specified prefix.  If
+  // the table index of blooms are not in memory, this may cause an I/O
+  bool PrefixMayMatch(const ReadOptions& options, uint64_t file_number,
+                      uint64_t file_size, const Slice& internal_prefix,
+                      bool* table_io);

  // Evict any entry for the specified file number
  void Evict(uint64_t file_number);
@@ -67,6 +75,4 @@ class TableCache {
                   const bool no_io = false);
 };

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_TABLE_CACHE_H_
+}  // namespace rocksdb
@@ -0,0 +1,55 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#include "db/table_stats_collector.h"
+
+#include "db/dbformat.h"
+#include "util/coding.h"
+
+namespace rocksdb {
+
+Status InternalKeyStatsCollector::Add(const Slice& key, const Slice& value) {
+  ParsedInternalKey ikey;
+  if (!ParseInternalKey(key, &ikey)) {
+    return Status::InvalidArgument("Invalid internal key");
+  }
+
+  if (ikey.type == ValueType::kTypeDeletion) {
+    ++deleted_keys_;
+  }
+
+  return Status::OK();
+}
+
+Status InternalKeyStatsCollector::Finish(
+    TableStats::UserCollectedStats* stats) {
+  assert(stats);
+  assert(stats->find(InternalKeyTableStatsNames::kDeletedKeys) == stats->end());
+  std::string val;
+
+  PutVarint64(&val, deleted_keys_);
+  stats->insert(std::make_pair(InternalKeyTableStatsNames::kDeletedKeys, val));
+
+  return Status::OK();
+}
+
+Status UserKeyTableStatsCollector::Add(const Slice& key, const Slice& value) {
+  ParsedInternalKey ikey;
+  if (!ParseInternalKey(key, &ikey)) {
+    return Status::InvalidArgument("Invalid internal key");
+  }
+
+  return collector_->Add(ikey.user_key, value);
+}
+
+Status UserKeyTableStatsCollector::Finish(
+    TableStats::UserCollectedStats* stats) {
+  return collector_->Finish(stats);
+}
+
+const std::string InternalKeyTableStatsNames::kDeletedKeys
+  = "rocksdb.deleted.keys";
+
+}  // namespace rocksdb
@@ -0,0 +1,58 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// This file defines a collection of statistics collectors.
+#pragma once
+
+#include "rocksdb/table_stats.h"
+
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace rocksdb {
+
+struct InternalKeyTableStatsNames {
+  static const std::string kDeletedKeys;
+};
+
+// Collecting the statistics for internal keys. Visible only by internal
+// rocksdb modules.
+class InternalKeyStatsCollector : public TableStatsCollector {
+ public:
+  virtual Status Add(const Slice& key, const Slice& value);
+  virtual Status Finish(TableStats::UserCollectedStats* stats);
+  virtual const char* Name() const { return "InternalKeyStatsCollector"; }
+
+ private:
+  uint64_t deleted_keys_ = 0;
+};
+
+// When rocksdb creates a new table, it will encode all "user keys" into
+// "internal keys", which contains meta information of a given entry.
+//
+// This class extracts user key from the encoded internal key when Add() is
+// invoked.
+class UserKeyTableStatsCollector : public TableStatsCollector {
+ public:
+  explicit UserKeyTableStatsCollector(TableStatsCollector* collector):
+    UserKeyTableStatsCollector(
+        std::shared_ptr<TableStatsCollector>(collector)
+    ) {
+  }
+
+  explicit UserKeyTableStatsCollector(
+      std::shared_ptr<TableStatsCollector> collector) : collector_(collector) {
+  }
+  virtual ~UserKeyTableStatsCollector() { }
+  virtual Status Add(const Slice& key, const Slice& value);
+  virtual Status Finish(TableStats::UserCollectedStats* stats);
+  virtual const char* Name() const { return collector_->Name(); }
+
+ protected:
+  std::shared_ptr<TableStatsCollector> collector_;
+};
+
+}  // namespace rocksdb
@@ -0,0 +1,258 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#include <map>
+#include <memory>
+#include <string>
+
+#include "db/dbformat.h"
+#include "db/db_impl.h"
+#include "db/table_stats_collector.h"
+#include "rocksdb/table_stats.h"
+#include "rocksdb/table.h"
+#include "util/coding.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+
+namespace rocksdb {
+
+class TableStatsTest {
+ private:
+  unique_ptr<TableReader> table_reader_;
+};
+
+// TODO(kailiu) the following classes should be moved to some more general
+// places, so that other tests can also make use of them.
+// `FakeWritableFile` and `FakeRandomeAccessFile` bypass the real file system
+// and therefore enable us to quickly setup the tests.
+class FakeWritableFile : public WritableFile {
+ public:
+  ~FakeWritableFile() { }
+
+  const std::string& contents() const { return contents_; }
+
+  virtual Status Close() { return Status::OK(); }
+  virtual Status Flush() { return Status::OK(); }
+  virtual Status Sync() { return Status::OK(); }
+
+  virtual Status Append(const Slice& data) {
+    contents_.append(data.data(), data.size());
+    return Status::OK();
+  }
+
+ private:
+  std::string contents_;
+};
+
+
+class FakeRandomeAccessFile : public RandomAccessFile {
+ public:
+  explicit FakeRandomeAccessFile(const Slice& contents)
+      : contents_(contents.data(), contents.size()) {
+  }
+
+  virtual ~FakeRandomeAccessFile() { }
+
+  uint64_t Size() const { return contents_.size(); }
+
+  virtual Status Read(uint64_t offset, size_t n, Slice* result,
+                       char* scratch) const {
+    if (offset > contents_.size()) {
+      return Status::InvalidArgument("invalid Read offset");
+    }
+    if (offset + n > contents_.size()) {
+      n = contents_.size() - offset;
+    }
+    memcpy(scratch, &contents_[offset], n);
+    *result = Slice(scratch, n);
+    return Status::OK();
+  }
+
+ private:
+  std::string contents_;
+};
+
+
+class DumbLogger : public Logger {
+ public:
+  virtual void Logv(const char* format, va_list ap) { }
+  virtual size_t GetLogFileSize() const { return 0; }
+};
+
+// Utilities test functions
+void MakeBuilder(
+    const Options& options,
+    std::unique_ptr<FakeWritableFile>* writable,
+    std::unique_ptr<TableBuilder>* builder) {
+  writable->reset(new FakeWritableFile);
+  builder->reset(
+      options.table_factory->GetTableBuilder(options, writable->get(),
+                                             options.compression));
+}
+
+void OpenTable(
+    const Options& options,
+    const std::string& contents,
+    std::unique_ptr<TableReader>* table_reader) {
+  std::unique_ptr<RandomAccessFile> file(new FakeRandomeAccessFile(contents));
+  auto s = options.table_factory->GetTableReader(
+      options,
+      EnvOptions(),
+      std::move(file),
+      contents.size(),
+      table_reader
+  );
+  ASSERT_OK(s);
+}
+
+// Collects keys that starts with "A" in a table.
+class RegularKeysStartWithA: public TableStatsCollector {
+ public:
+   const char* Name() const { return "RegularKeysStartWithA"; }
+
+   Status Finish(TableStats::UserCollectedStats* stats) {
+     std::string encoded;
+     PutVarint32(&encoded, count_);
+     *stats = TableStats::UserCollectedStats {
+       { "TableStatsTest", "Rocksdb" },
+       { "Count", encoded }
+     };
+     return Status::OK();
+   }
+
+   Status Add(const Slice& user_key, const Slice& value) {
+     // simply asssume all user keys are not empty.
+     if (user_key.data()[0] == 'A') {
+       ++count_;
+     }
+     return Status::OK();
+   }
+
+ private:
+  uint32_t count_ = 0;
+};
+
+TEST(TableStatsTest, CustomizedTableStatsCollector) {
+  Options options;
+
+  // make sure the entries will be inserted with order.
+  std::map<std::string, std::string> kvs = {
+    {"About",     "val5"},  // starts with 'A'
+    {"Abstract",  "val2"},  // starts with 'A'
+    {"Around",    "val7"},  // starts with 'A'
+    {"Beyond",    "val3"},
+    {"Builder",   "val1"},
+    {"Cancel",    "val4"},
+    {"Find",      "val6"},
+  };
+
+  // Test stats collectors with internal keys or regular keys
+  for (bool encode_as_internal : { true, false }) {
+    // -- Step 1: build table
+    auto collector = new RegularKeysStartWithA();
+    if (encode_as_internal) {
+      options.table_stats_collectors = {
+        std::make_shared<UserKeyTableStatsCollector>(collector)
+      };
+    } else {
+      options.table_stats_collectors.resize(1);
+      options.table_stats_collectors[0].reset(collector);
+    }
+    std::unique_ptr<TableBuilder> builder;
+    std::unique_ptr<FakeWritableFile> writable;
+    MakeBuilder(options, &writable, &builder);
+
+    for (const auto& kv : kvs) {
+      if (encode_as_internal) {
+        InternalKey ikey(kv.first, 0, ValueType::kTypeValue);
+        builder->Add(ikey.Encode(), kv.second);
+      } else {
+        builder->Add(kv.first, kv.second);
+      }
+    }
+    ASSERT_OK(builder->Finish());
+
+    // -- Step 2: Open table
+    std::unique_ptr<TableReader> table_reader;
+    OpenTable(options, writable->contents(), &table_reader);
+    const auto& stats = table_reader->GetTableStats().user_collected_stats;
+
+    ASSERT_EQ("Rocksdb", stats.at("TableStatsTest"));
+
+    uint32_t starts_with_A = 0;
+    Slice key(stats.at("Count"));
+    ASSERT_TRUE(GetVarint32(&key, &starts_with_A));
+    ASSERT_EQ(3u, starts_with_A);
+  }
+}
+
+TEST(TableStatsTest, InternalKeyStatsCollector) {
+  InternalKey keys[] = {
+    InternalKey("A", 0, ValueType::kTypeValue),
+    InternalKey("B", 0, ValueType::kTypeValue),
+    InternalKey("C", 0, ValueType::kTypeValue),
+    InternalKey("W", 0, ValueType::kTypeDeletion),
+    InternalKey("X", 0, ValueType::kTypeDeletion),
+    InternalKey("Y", 0, ValueType::kTypeDeletion),
+    InternalKey("Z", 0, ValueType::kTypeDeletion),
+  };
+
+  for (bool sanitized : { false, true }) {
+    std::unique_ptr<TableBuilder> builder;
+    std::unique_ptr<FakeWritableFile> writable;
+    Options options;
+    if (sanitized) {
+      options.table_stats_collectors = {
+        std::make_shared<RegularKeysStartWithA>()
+      };
+      // with sanitization, even regular stats collector will be able to
+      // handle internal keys.
+      auto comparator = options.comparator;
+      // HACK: Set options.info_log to avoid writing log in
+      // SanitizeOptions().
+      options.info_log = std::make_shared<DumbLogger>();
+      options = SanitizeOptions(
+          "db",  // just a place holder
+          nullptr,  // with skip internal key comparator
+          nullptr,  // don't care filter policy
+          options
+      );
+      options.comparator = comparator;
+    } else {
+      options.table_stats_collectors = {
+        std::make_shared<InternalKeyStatsCollector>()
+      };
+    }
+
+    MakeBuilder(options, &writable, &builder);
+    for (const auto& k : keys) {
+      builder->Add(k.Encode(), "val");
+    }
+
+    ASSERT_OK(builder->Finish());
+
+    std::unique_ptr<TableReader> table_reader;
+    OpenTable(options, writable->contents(), &table_reader);
+    const auto& stats = table_reader->GetTableStats().user_collected_stats;
+
+    uint64_t deleted = 0;
+    Slice key(stats.at(InternalKeyTableStatsNames::kDeletedKeys));
+    ASSERT_TRUE(GetVarint64(&key, &deleted));
+    ASSERT_EQ(4u, deleted);
+
+    if (sanitized) {
+      uint32_t starts_with_A = 0;
+      Slice key(stats.at("Count"));
+      ASSERT_TRUE(GetVarint32(&key, &starts_with_A));
+      ASSERT_EQ(1u, starts_with_A);
+    }
+  }
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}
@@ -0,0 +1,259 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+#include "db/transaction_log_impl.h"
+#include "db/write_batch_internal.h"
+
+namespace rocksdb {
+
+TransactionLogIteratorImpl::TransactionLogIteratorImpl(
+                           const std::string& dir,
+                           const Options* options,
+                           const EnvOptions& soptions,
+                           const SequenceNumber seq,
+                           std::unique_ptr<VectorLogPtr> files,
+                           DBImpl const * const dbimpl) :
+    dir_(dir),
+    options_(options),
+    soptions_(soptions),
+    startingSequenceNumber_(seq),
+    files_(std::move(files)),
+    started_(false),
+    isValid_(false),
+    currentFileIndex_(0),
+    currentBatchSeq_(0),
+    currentLastSeq_(0),
+    dbimpl_(dbimpl) {
+  assert(files_ != nullptr);
+  assert(dbimpl_ != nullptr);
+
+  reporter_.env = options_->env;
+  reporter_.info_log = options_->info_log.get();
+  SeekToStartSequence(); // Seek till starting sequence
+}
+
+Status TransactionLogIteratorImpl::OpenLogFile(
+    const LogFile* logFile,
+    unique_ptr<SequentialFile>* file) {
+  Env* env = options_->env;
+  if (logFile->Type() == kArchivedLogFile) {
+    std::string fname = ArchivedLogFileName(dir_, logFile->LogNumber());
+    return env->NewSequentialFile(fname, file, soptions_);
+  } else {
+    std::string fname = LogFileName(dir_, logFile->LogNumber());
+    Status status = env->NewSequentialFile(fname, file, soptions_);
+    if (!status.ok()) {
+      //  If cannot open file in DB directory.
+      //  Try the archive dir, as it could have moved in the meanwhile.
+      fname = ArchivedLogFileName(dir_, logFile->LogNumber());
+      status = env->NewSequentialFile(fname, file, soptions_);
+      if (!status.ok()) {
+        return Status::IOError("Requested file not present in the dir");
+      }
+    }
+    return status;
+  }
+}
+
+BatchResult TransactionLogIteratorImpl::GetBatch()  {
+  assert(isValid_);  //  cannot call in a non valid state.
+  BatchResult result;
+  result.sequence = currentBatchSeq_;
+  result.writeBatchPtr = std::move(currentBatch_);
+  return result;
+}
+
+Status TransactionLogIteratorImpl::status() {
+  return currentStatus_;
+}
+
+bool TransactionLogIteratorImpl::Valid() {
+  return started_ && isValid_;
+}
+
+bool TransactionLogIteratorImpl::RestrictedRead(
+    Slice* record,
+    std::string* scratch) {
+  // Don't read if no more complete entries to read from logs
+  if (currentLastSeq_ >= dbimpl_->GetLatestSequenceNumber()) {
+    return false;
+  }
+  return currentLogReader_->ReadRecord(record, scratch);
+}
+
+void TransactionLogIteratorImpl::SeekToStartSequence(
+    uint64_t startFileIndex,
+    bool strict) {
+  std::string scratch;
+  Slice record;
+  started_ = false;
+  isValid_ = false;
+  if (files_->size() <= startFileIndex) {
+    return;
+  }
+  Status s = OpenLogReader(files_->at(startFileIndex).get());
+  if (!s.ok()) {
+    currentStatus_ = s;
+    return;
+  }
+  while (RestrictedRead(&record, &scratch)) {
+    if (record.size() < 12) {
+      reporter_.Corruption(
+        record.size(), Status::Corruption("very small log record"));
+      continue;
+    }
+    UpdateCurrentWriteBatch(record);
+    if (currentLastSeq_ >= startingSequenceNumber_) {
+      if (strict && currentBatchSeq_ != startingSequenceNumber_) {
+        currentStatus_ = Status::Corruption("Gap in sequence number. Could not "
+                                            "seek to required sequence number");
+        reporter_.Info(currentStatus_.ToString().c_str());
+        return;
+      } else if (strict) {
+        reporter_.Info("Could seek required sequence number. Iterator will "
+                       "continue.");
+      }
+      isValid_ = true;
+      started_ = true; // set started_ as we could seek till starting sequence
+      return;
+    } else {
+      isValid_ = false;
+    }
+  }
+
+  // Could not find start sequence in first file. Normally this must be the
+  // only file. Otherwise log the error and let the iterator return next entry
+  // If strict is set, we want to seek exactly till the start sequence and it
+  // should have been present in the file we scanned above
+  if (strict) {
+    currentStatus_ = Status::Corruption("Gap in sequence number. Could not "
+                                        "seek to required sequence number");
+    reporter_.Info(currentStatus_.ToString().c_str());
+  } else if (files_->size() != 1) {
+    currentStatus_ = Status::Corruption("Start sequence was not found, "
+                                        "skipping to the next available");
+    reporter_.Info(currentStatus_.ToString().c_str());
+    // Let NextImpl find the next available entry. started_ remains false
+    // because we don't want to check for gaps while moving to start sequence
+    NextImpl(true);
+  }
+}
+
+void TransactionLogIteratorImpl::Next() {
+  return NextImpl(false);
+}
+
+void TransactionLogIteratorImpl::NextImpl(bool internal) {
+  std::string scratch;
+  Slice record;
+  isValid_ = false;
+  if (!internal && !started_) {
+    // Runs every time until we can seek to the start sequence
+    return SeekToStartSequence();
+  }
+  while(true) {
+    assert(currentLogReader_);
+    if (currentLogReader_->IsEOF()) {
+      currentLogReader_->UnmarkEOF();
+    }
+    while (RestrictedRead(&record, &scratch)) {
+      if (record.size() < 12) {
+        reporter_.Corruption(
+          record.size(), Status::Corruption("very small log record"));
+        continue;
+      } else {
+        // started_ should be true if called by application
+        assert(internal || started_);
+        // started_ should be false if called internally
+        assert(!internal || !started_);
+        UpdateCurrentWriteBatch(record);
+        if (internal && !started_) {
+          started_ = true;
+        }
+        return;
+      }
+    }
+
+    // Open the next file
+    if (currentFileIndex_ < files_->size() - 1) {
+      ++currentFileIndex_;
+      Status status =OpenLogReader(files_->at(currentFileIndex_).get());
+      if (!status.ok()) {
+        isValid_ = false;
+        currentStatus_ = status;
+        return;
+      }
+    } else {
+      isValid_ = false;
+      if (currentLastSeq_ == dbimpl_->GetLatestSequenceNumber()) {
+        currentStatus_ = Status::OK();
+      } else {
+        currentStatus_ = Status::IOError("NO MORE DATA LEFT");
+      }
+      return;
+    }
+  }
+}
+
+bool TransactionLogIteratorImpl::IsBatchExpected(
+    const WriteBatch* batch,
+    const SequenceNumber expectedSeq) {
+  assert(batch);
+  SequenceNumber batchSeq = WriteBatchInternal::Sequence(batch);
+  if (batchSeq != expectedSeq) {
+    char buf[200];
+    snprintf(buf, sizeof(buf),
+             "Discontinuity in log records. Got seq=%lu, Expected seq=%lu, "
+             "Last flushed seq=%lu.Log iterator will reseek the correct batch.",
+             batchSeq, expectedSeq, dbimpl_->GetLatestSequenceNumber());
+    reporter_.Info(buf);
+    return false;
+  }
+  return true;
+}
+
+void TransactionLogIteratorImpl::UpdateCurrentWriteBatch(const Slice& record) {
+  std::unique_ptr<WriteBatch> batch(new WriteBatch());
+  WriteBatchInternal::SetContents(batch.get(), record);
+
+  SequenceNumber expectedSeq = currentLastSeq_ + 1;
+  // If the iterator has started, then confirm that we get continuous batches
+  if (started_ && !IsBatchExpected(batch.get(), expectedSeq)) {
+    // Seek to the batch having expected sequence number
+    if (expectedSeq < files_->at(currentFileIndex_)->StartSequence()) {
+      // Expected batch must lie in the previous log file
+      currentFileIndex_--;
+      currentFileIndex_ = (currentFileIndex_ >= 0) ? currentFileIndex_ : 0;
+    }
+    startingSequenceNumber_ = expectedSeq;
+    // currentStatus_ will be set to Ok if reseek succeeds
+    currentStatus_ = Status::NotFound("Gap in sequence numbers");
+    return SeekToStartSequence(currentFileIndex_, true);
+  }
+
+  currentBatchSeq_ = WriteBatchInternal::Sequence(batch.get());
+  currentLastSeq_ = currentBatchSeq_ +
+                    WriteBatchInternal::Count(batch.get()) - 1;
+  // currentBatchSeq_ can only change here
+  assert(currentLastSeq_ <= dbimpl_->GetLatestSequenceNumber());
+
+  currentBatch_ = move(batch);
+  isValid_ = true;
+  currentStatus_ = Status::OK();
+}
+
+Status TransactionLogIteratorImpl::OpenLogReader(const LogFile* logFile) {
+  unique_ptr<SequentialFile> file;
+  Status status = OpenLogFile(logFile, &file);
+  if (!status.ok()) {
+    return status;
+  }
+  assert(file);
+  currentLogReader_.reset(
+    new log::Reader(std::move(file), &reporter_, true, 0)
+  );
+  return Status::OK();
+}
+}  //  namespace rocksdb
@@ -0,0 +1,118 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+#pragma once
+#include <vector>
+
+#include "rocksdb/env.h"
+#include "rocksdb/options.h"
+#include "rocksdb/types.h"
+#include "rocksdb/transaction_log.h"
+#include "db/db_impl.h"
+#include "db/log_reader.h"
+#include "db/filename.h"
+
+namespace rocksdb {
+
+struct LogReporter : public log::Reader::Reporter {
+  Env* env;
+  Logger* info_log;
+  virtual void Corruption(size_t bytes, const Status& s) {
+    Log(info_log, "dropping %zu bytes; %s", bytes, s.ToString().c_str());
+  }
+  virtual void Info(const char* s) {
+    Log(info_log, "%s", s);
+  }
+};
+
+class LogFileImpl : public LogFile {
+ public:
+  LogFileImpl(uint64_t logNum, WalFileType logType, SequenceNumber startSeq,
+              uint64_t sizeBytes) :
+    logNumber_(logNum),
+    type_(logType),
+    startSequence_(startSeq),
+    sizeFileBytes_(sizeBytes) {
+  }
+
+  std::string PathName() const {
+    if (type_ == kArchivedLogFile) {
+      return ArchivedLogFileName("", logNumber_);
+    }
+    return LogFileName("", logNumber_);
+  }
+
+  uint64_t LogNumber() const { return logNumber_; }
+
+  WalFileType Type() const { return type_; }
+
+  SequenceNumber StartSequence() const { return startSequence_; }
+
+  uint64_t SizeFileBytes() const { return sizeFileBytes_; }
+
+  bool operator < (const LogFile& that) const {
+    return LogNumber() < that.LogNumber();
+  }
+
+ private:
+  uint64_t logNumber_;
+  WalFileType type_;
+  SequenceNumber startSequence_;
+  uint64_t sizeFileBytes_;
+
+};
+
+class TransactionLogIteratorImpl : public TransactionLogIterator {
+ public:
+  TransactionLogIteratorImpl(const std::string& dir,
+                             const Options* options,
+                             const EnvOptions& soptions,
+                             const SequenceNumber seqNum,
+                             std::unique_ptr<VectorLogPtr> files,
+                             DBImpl const * const dbimpl);
+
+  virtual bool Valid();
+
+  virtual void Next();
+
+  virtual Status status();
+
+  virtual BatchResult GetBatch();
+
+ private:
+  const std::string& dir_;
+  const Options* options_;
+  const EnvOptions& soptions_;
+  SequenceNumber startingSequenceNumber_;
+  std::unique_ptr<VectorLogPtr> files_;
+  bool started_;
+  bool isValid_;  // not valid when it starts of.
+  Status currentStatus_;
+  size_t currentFileIndex_;
+  std::unique_ptr<WriteBatch> currentBatch_;
+  unique_ptr<log::Reader> currentLogReader_;
+  Status OpenLogFile(const LogFile* logFile, unique_ptr<SequentialFile>* file);
+  LogReporter reporter_;
+  SequenceNumber currentBatchSeq_; // sequence number at start of current batch
+  SequenceNumber currentLastSeq_; // last sequence in the current batch
+  DBImpl const * const dbimpl_; // The db on whose log files this iterates
+
+  // Reads from transaction log only if the writebatch record has been written
+  bool RestrictedRead(Slice* record, std::string* scratch);
+  // Seeks to startingSequenceNumber reading from startFileIndex in files_.
+  // If strict is set,then must get a batch starting with startingSequenceNumber
+  void SeekToStartSequence(uint64_t startFileIndex = 0, bool strict = false);
+  // Implementation of Next. SeekToStartSequence calls it internally with
+  // internal=true to let it find next entry even if it has to jump gaps because
+  // the iterator may start off from the first available entry but promises to
+  // be continuous after that
+  void NextImpl(bool internal = false);
+  // Check if batch is expected, else return false
+  bool IsBatchExpected(const WriteBatch* batch, SequenceNumber expectedSeq);
+  // Update current batch if a continuous batch is found, else return false
+  void UpdateCurrentWriteBatch(const Slice& record);
+  Status OpenLogReader(const LogFile* file);
+};
+}  //  namespace rocksdb
@@ -1,172 +0,0 @@
-#include "db/transaction_log_iterator_impl.h"
-#include "db/write_batch_internal.h"
-#include "db/filename.h"
-
-namespace leveldb {
-
-TransactionLogIteratorImpl::TransactionLogIteratorImpl(
-                           const std::string& dbname,
-                           const Options* options,
-                           const EnvOptions& soptions,
-                           SequenceNumber& seq,
-                           std::unique_ptr<std::vector<LogFile>> files,
-                           SequenceNumber const * const lastFlushedSequence) :
-  dbname_(dbname),
-  options_(options),
-  soptions_(soptions),
-  startingSequenceNumber_(seq),
-  files_(std::move(files)),
-  started_(false),
-  isValid_(false),
-  currentFileIndex_(0),
-  lastFlushedSequence_(lastFlushedSequence) {
-  assert(files_.get() != nullptr);
-  assert(lastFlushedSequence_);
-
-  reporter_.env = options_->env;
-  reporter_.info_log = options_->info_log.get();
-}
-
-Status TransactionLogIteratorImpl::OpenLogFile(
-  const LogFile& logFile,
-  unique_ptr<SequentialFile>* file) {
-  Env* env = options_->env;
-  if (logFile.type == kArchivedLogFile) {
-    std::string fname = ArchivedLogFileName(dbname_, logFile.logNumber);
-    return env->NewSequentialFile(fname, file, soptions_);
-  } else {
-    std::string fname = LogFileName(dbname_, logFile.logNumber);
-    Status status = env->NewSequentialFile(fname, file, soptions_);
-    if (!status.ok()) {
-      //  If cannot open file in DB directory.
-      //  Try the archive dir, as it could have moved in the meanwhile.
-      fname = ArchivedLogFileName(dbname_, logFile.logNumber);
-      status = env->NewSequentialFile(fname, file, soptions_);
-      if (!status.ok()) {
-        return Status::IOError(" Requested file not present in the dir");
-      }
-    }
-    return status;
-  }
-}
-
-BatchResult TransactionLogIteratorImpl::GetBatch()  {
-  assert(isValid_);  //  cannot call in a non valid state.
-  BatchResult result;
-  result.sequence = currentSequence_;
-  result.writeBatchPtr = std::move(currentBatch_);
-  return result;
-}
-
-Status TransactionLogIteratorImpl::status() {
-  return currentStatus_;
-}
-
-bool TransactionLogIteratorImpl::Valid() {
-  return started_ && isValid_;
-}
-
-void TransactionLogIteratorImpl::Next() {
-  LogFile currentLogFile = files_.get()->at(currentFileIndex_);
-
-//  First seek to the given seqNo. in the current file.
-  std::string scratch;
-  Slice record;
-  if (!started_) {
-    started_ = true;  // this piece only runs onced.
-    isValid_ = false;
-    if (startingSequenceNumber_ > *lastFlushedSequence_) {
-      currentStatus_ = Status::IOError("Looking for a sequence, "
-                                        "which is not flushed yet.");
-      return;
-    }
-    Status s = OpenLogReader(currentLogFile);
-    if (!s.ok()) {
-      currentStatus_ = s;
-      isValid_ = false;
-      return;
-    }
-    while (currentLogReader_->ReadRecord(&record, &scratch)) {
-      if (record.size() < 12) {
-        reporter_.Corruption(
-          record.size(), Status::Corruption("log record too small"));
-        continue;
-      }
-      UpdateCurrentWriteBatch(record);
-      if (currentSequence_ >= startingSequenceNumber_) {
-        assert(currentSequence_ <= *lastFlushedSequence_);
-        isValid_ = true;
-        break;
-      } else {
-        isValid_ = false;
-      }
-    }
-    if (isValid_) {
-      // Done for this iteration
-      return;
-    }
-  }
-  bool openNextFile = true;
-  while(openNextFile) {
-    assert(currentLogReader_);
-    if (currentSequence_ < *lastFlushedSequence_) {
-      if (currentLogReader_->IsEOF()) {
-        currentLogReader_->UnmarkEOF();
-      }
-      while (currentLogReader_->ReadRecord(&record, &scratch)) {
-        if (record.size() < 12) {
-          reporter_.Corruption(
-            record.size(), Status::Corruption("log record too small"));
-          continue;
-        } else {
-          UpdateCurrentWriteBatch(record);
-          openNextFile = false;
-          break;
-        }
-      }
-    }
-
-    if (openNextFile) {
-      if (currentFileIndex_ < files_.get()->size() - 1) {
-        ++currentFileIndex_;
-        Status status = OpenLogReader(files_.get()->at(currentFileIndex_));
-        if (!status.ok()) {
-          isValid_ = false;
-          currentStatus_ = status;
-          return;
-        }
-      } else {
-        isValid_ = false;
-        openNextFile = false;
-        if (currentSequence_ == *lastFlushedSequence_) {
-          currentStatus_ = Status::OK();
-        } else {
-          currentStatus_ = Status::IOError(" NO MORE DATA LEFT");
-        }
-      }
-    }
-  }
-}
-
-void TransactionLogIteratorImpl::UpdateCurrentWriteBatch(const Slice& record) {
-  WriteBatch* batch = new WriteBatch();
-  WriteBatchInternal::SetContents(batch, record);
-  currentSequence_ = WriteBatchInternal::Sequence(batch);
-  currentBatch_.reset(batch);
-  isValid_ = true;
-  currentStatus_ = Status::OK();
-}
-
-Status TransactionLogIteratorImpl::OpenLogReader(const LogFile& logFile) {
-  unique_ptr<SequentialFile> file;
-  Status status = OpenLogFile(logFile, &file);
-  if (!status.ok()) {
-    return status;
-  }
-  assert(file);
-  currentLogReader_.reset(
-    new log::Reader(std::move(file), &reporter_, true, 0)
-  );
-  return Status::OK();
-}
-}  //  namespace leveldb
@@ -1,66 +0,0 @@
-// Copyright 2008-present Facebook. All Rights Reserved.
-#ifndef STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
-#define STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
-
-#include <vector>
-
-#include "leveldb/env.h"
-#include "leveldb/options.h"
-#include "leveldb/types.h"
-#include "leveldb/transaction_log_iterator.h"
-#include "db/log_file.h"
-#include "db/log_reader.h"
-
-namespace leveldb {
-
-struct LogReporter : public log::Reader::Reporter {
-  Env* env;
-  Logger* info_log;
-  virtual void Corruption(size_t bytes, const Status& s) {
-    Log(info_log, "dropping %zu bytes; %s", bytes, s.ToString().c_str());
-  }
-};
-
-class TransactionLogIteratorImpl : public TransactionLogIterator {
- public:
-  TransactionLogIteratorImpl(const std::string& dbname,
-                             const Options* options,
-                             const EnvOptions& soptions,
-                             SequenceNumber& seqNum,
-                             std::unique_ptr<std::vector<LogFile>> files,
-                             SequenceNumber const * const lastFlushedSequence);
-
-  virtual bool Valid();
-
-  virtual void Next();
-
-  virtual Status status();
-
-  virtual BatchResult GetBatch();
-
- private:
-  const std::string& dbname_;
-  const Options* options_;
-  const EnvOptions& soptions_;
-  const uint64_t startingSequenceNumber_;
-  std::unique_ptr<std::vector<LogFile>> files_;
-  bool started_;
-  bool isValid_;  // not valid when it starts of.
-  Status currentStatus_;
-  size_t currentFileIndex_;
-  std::unique_ptr<WriteBatch> currentBatch_;
-  unique_ptr<log::Reader> currentLogReader_;
-  Status OpenLogFile(const LogFile& logFile, unique_ptr<SequentialFile>* file);
-  LogReporter reporter_;
-  SequenceNumber const * const lastFlushedSequence_;
-  // represents the sequence number being read currently.
-  SequenceNumber currentSequence_;
-
-  void UpdateCurrentWriteBatch(const Slice& record);
-  Status OpenLogReader(const LogFile& file);
-};
-
-
-
-}  //  namespace leveldb
-#endif  //  STORAGE_LEVELDB_INCLUDE_WRITES_ITERATOR_IMPL_H_
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -7,7 +12,7 @@
 #include "db/version_set.h"
 #include "util/coding.h"

-namespace leveldb {
+namespace rocksdb {

 // Tag numbers for serialized VersionEdit.  These numbers are written to
 // disk and should not be changed.
@@ -20,7 +25,10 @@ enum Tag {
  kDeletedFile          = 6,
  kNewFile              = 7,
  // 8 was used for large value refs
-  kPrevLogNumber        = 9
+  kPrevLogNumber        = 9,
+
+  // these are new formats divergent from open source leveldb
+  kNewFile2             = 100  // store smallest & largest seqno
 };

 void VersionEdit::Clear() {
@@ -76,12 +84,14 @@ void VersionEdit::EncodeTo(std::string* dst) const {

  for (size_t i = 0; i < new_files_.size(); i++) {
    const FileMetaData& f = new_files_[i].second;
-    PutVarint32(dst, kNewFile);
+    PutVarint32(dst, kNewFile2);
    PutVarint32(dst, new_files_[i].first);  // level
    PutVarint64(dst, f.number);
    PutVarint64(dst, f.file_size);
    PutLengthPrefixedSlice(dst, f.smallest.Encode());
    PutLengthPrefixedSlice(dst, f.largest.Encode());
+    PutVarint64(dst, f.smallest_seqno);
+    PutVarint64(dst, f.largest_seqno);
  }
 }

@@ -201,6 +211,22 @@ Status VersionEdit::DecodeFrom(const Slice& src) {
        }
        break;

+      case kNewFile2:
+        if (GetLevel(&input, &level, &msg) &&
+            GetVarint64(&input, &f.number) &&
+            GetVarint64(&input, &f.file_size) &&
+            GetInternalKey(&input, &f.smallest) &&
+            GetInternalKey(&input, &f.largest) &&
+            GetVarint64(&input, &f.smallest_seqno) &&
+            GetVarint64(&input, &f.largest_seqno) ) {
+          new_files_.push_back(std::make_pair(level, f));
+        } else {
+          if (!msg) {
+            msg = "new-file2 entry";
+          }
+        }
+        break;
+
      default:
        msg = "unknown tag";
        break;
@@ -218,7 +244,7 @@ Status VersionEdit::DecodeFrom(const Slice& src) {
  return result;
 }

-std::string VersionEdit::DebugString() const {
+std::string VersionEdit::DebugString(bool hex_key) const {
  std::string r;
  r.append("VersionEdit {");
  if (has_comparator_) {
@@ -245,7 +271,7 @@ std::string VersionEdit::DebugString() const {
    r.append("\n  CompactPointer: ");
    AppendNumberTo(&r, compact_pointers_[i].first);
    r.append(" ");
-    r.append(compact_pointers_[i].second.DebugString());
+    r.append(compact_pointers_[i].second.DebugString(hex_key));
  }
  for (DeletedFileSet::const_iterator iter = deleted_files_.begin();
       iter != deleted_files_.end();
@@ -264,12 +290,12 @@ std::string VersionEdit::DebugString() const {
    r.append(" ");
    AppendNumberTo(&r, f.file_size);
    r.append(" ");
-    r.append(f.smallest.DebugString());
+    r.append(f.smallest.DebugString(hex_key));
    r.append(" .. ");
-    r.append(f.largest.DebugString());
+    r.append(f.largest.DebugString(hex_key));
  }
  r.append("\n}\n");
  return r;
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,16 +1,19 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_VERSION_EDIT_H_
-#define STORAGE_LEVELDB_DB_VERSION_EDIT_H_
-
+#pragma once
 #include <set>
 #include <utility>
 #include <vector>
 #include "db/dbformat.h"

-namespace leveldb {
+namespace rocksdb {

 class VersionSet;

@@ -22,6 +25,8 @@ struct FileMetaData {
  InternalKey smallest;       // Smallest internal key served by table
  InternalKey largest;        // Largest internal key served by table
  bool being_compacted;       // Is this file undergoing compaction?
+  SequenceNumber smallest_seqno;// The smallest seqno in this file
+  SequenceNumber largest_seqno; // The largest seqno in this file

  FileMetaData() : refs(0), allowed_seeks(1 << 30), file_size(0),
                   being_compacted(false) { }
@@ -29,9 +34,9 @@ struct FileMetaData {

 class VersionEdit {
 public:
-  /* implicit */ VersionEdit(int number_levels) :
-  number_levels_(number_levels) {
-  Clear();
+  explicit VersionEdit(int number_levels) :
+      number_levels_(number_levels) {
+    Clear();
  }
  ~VersionEdit() { }

@@ -67,12 +72,17 @@ class VersionEdit {
  void AddFile(int level, uint64_t file,
               uint64_t file_size,
               const InternalKey& smallest,
-               const InternalKey& largest) {
+               const InternalKey& largest,
+               const SequenceNumber& smallest_seqno,
+               const SequenceNumber& largest_seqno) {
    FileMetaData f;
    f.number = file;
    f.file_size = file_size;
    f.smallest = smallest;
    f.largest = largest;
+    f.smallest_seqno = smallest_seqno;
+    f.largest_seqno = largest_seqno;
+    assert(smallest_seqno <= largest_seqno);
    new_files_.push_back(std::make_pair(level, f));
  }

@@ -89,7 +99,7 @@ class VersionEdit {
  void EncodeTo(std::string* dst) const;
  Status DecodeFrom(const Slice& src);

-  std::string DebugString() const;
+  std::string DebugString(bool hex_key = false) const;

 private:
  friend class VersionSet;
@@ -115,6 +125,4 @@ class VersionEdit {
  std::vector< std::pair<int, FileMetaData> > new_files_;
 };

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_VERSION_EDIT_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -5,7 +10,7 @@
 #include "db/version_edit.h"
 #include "util/testharness.h"

-namespace leveldb {
+namespace rocksdb {

 static void TestEncodeDecode(const VersionEdit& edit) {
  std::string encoded, encoded2;
@@ -27,7 +32,9 @@ TEST(VersionEditTest, EncodeDecode) {
    TestEncodeDecode(edit);
    edit.AddFile(3, kBig + 300 + i, kBig + 400 + i,
                 InternalKey("foo", kBig + 500 + i, kTypeValue),
-                 InternalKey("zoo", kBig + 600 + i, kTypeDeletion));
+                 InternalKey("zoo", kBig + 600 + i, kTypeDeletion),
+                 kBig + 500 + i,
+                 kBig + 600 + i);
    edit.DeleteFile(4, kBig + 700 + i);
    edit.SetCompactPointer(i, InternalKey("x", kBig + 900 + i, kTypeValue));
  }
@@ -39,8 +46,8 @@ TEST(VersionEditTest, EncodeDecode) {
  TestEncodeDecode(edit);
 }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -12,9 +17,7 @@
 // Version,VersionSet are thread-compatible, but require external
 // synchronization on all accesses.

-#ifndef STORAGE_LEVELDB_DB_VERSION_SET_H_
-#define STORAGE_LEVELDB_DB_VERSION_SET_H_
-
+#pragma once
 #include <map>
 #include <memory>
 #include <set>
@@ -25,18 +28,16 @@
 #include "port/port.h"
 #include "db/table_cache.h"

-namespace leveldb {
+namespace rocksdb {

 namespace log { class Writer; }

 class Compaction;
 class Iterator;
 class MemTable;
-class TableBuilder;
 class TableCache;
 class Version;
 class VersionSet;
-class WritableFile;

 // Return the smallest index i such that files[i]->largest >= key.
 // Return files.size() if there is no such file.
@@ -76,7 +77,7 @@ class Version {
  };
  void Get(const ReadOptions&, const LookupKey& key, std::string* val,
           Status* status, std::deque<std::string>* operands, GetStats* stats,
-           const Options& db_option, const bool no_io = false,
+           const Options& db_option,
           bool* value_found = nullptr);

  // Adds "stats" into the current state.  Returns true if a new
@@ -152,6 +153,8 @@ class Version {
  Iterator* NewConcatenatingIterator(const ReadOptions&,
                                     const EnvOptions& soptions,
                                     int level) const;
+  bool PrefixMayMatch(const ReadOptions& options, const EnvOptions& soptions,
+                      const Slice& internal_prefix, Iterator* level_iter) const;

  VersionSet* vset_;            // VersionSet to which this Version belongs
  Version* next_;               // Next version in linked list
@@ -314,7 +317,17 @@ class VersionSet {
  // Returns true iff some level needs a compaction because it has
  // exceeded its target size.
  bool NeedsSizeCompaction() const {
-    for (int i = 0; i < NumberLevels()-1; i++) {
+    // In universal compaction case, this check doesn't really
+    // check the compaction condition, but checks num of files threshold
+    // only. We are not going to miss any compaction opportunity
+    // but it's likely that more compactions are scheduled but
+    // ending up with nothing to do. We can improve it later.
+    // TODO: improve this function to be accurate for universal
+    //       compactions.
+    int num_levels_to_check =
+        (options_->compaction_style != kCompactionStyleUniversal) ?
+            NumberLevels() - 1 : 1;
+    for (int i = 0; i < num_levels_to_check; i++) {
      if (current_->compaction_score_[i] >= 1) {
        return true;
      }
@@ -352,6 +365,9 @@ class VersionSet {
  struct LevelSummaryStorage {
    char buffer[100];
  };
+  struct FileSummaryStorage {
+    char buffer[1000];
+  };
  const char* LevelSummary(LevelSummaryStorage* scratch) const;

  // printf contents (for debugging)
@@ -362,6 +378,10 @@ class VersionSet {
  // of files per level.  Uses *scratch as backing store.
  const char* LevelDataSizeSummary(LevelSummaryStorage* scratch) const;

+  // Return a human-readable short (single-line) summary of files
+  // in a specified level.  Uses *scratch as backing store.
+  const char* LevelFileSummary(FileSummaryStorage* scratch, int level) const;
+
  // Return the size of the current manifest file
  const uint64_t ManifestFileSize() { return current_->offset_manifest_file_; }

@@ -371,6 +391,16 @@ class VersionSet {
  // function will return nullptr.
  Compaction* PickCompactionBySize(int level, double score);

+  // Pick files to compact in Universal mode
+  Compaction* PickCompactionUniversal(int level, double score);
+
+  // Pick Universal compaction to limit read amplification
+  Compaction* PickCompactionUniversalReadAmp(int level, double score,
+                unsigned int ratio, unsigned int num_files);
+
+  // Pick Universal compaction to limit space amplification.
+  Compaction* PickCompactionUniversalSizeAmp(int level, double score);
+
  // Free up the files that were participated in a compaction
  void ReleaseCompactionFiles(Compaction* c, Status status);

@@ -395,6 +425,12 @@ class VersionSet {

  double MaxBytesForLevel(int level);

+  Status GetMetadataForFile(
+    uint64_t number, int *filelevel, FileMetaData *metadata);
+
+  void GetLiveFilesMetaData(
+    std::vector<LiveFileMetaData> *metadata);
+
 private:
  class Builder;
  struct ManifestWriter;
@@ -426,9 +462,9 @@ class VersionSet {

  bool ManifestContains(const std::string& record) const;

-  int64_t ExpandedCompactionByteSizeLimit(int level);
+  uint64_t ExpandedCompactionByteSizeLimit(int level);

-  int64_t MaxGrandParentOverlapBytes(int level);
+  uint64_t MaxGrandParentOverlapBytes(int level);

  Env* const env_;
  const std::string dbname_;
@@ -503,9 +539,12 @@ class Compaction {
  ~Compaction();

  // Return the level that is being compacted.  Inputs from "level"
-  // and "level+1" will be merged to produce a set of "level+1" files.
+  // will be merged.
  int level() const { return level_; }

+  // Outputs will go to this level
+  int output_level() const { return out_level_; }
+
  // Return the object that holds the edits to the descriptor done
  // by this compaction.
  VersionEdit* edit() { return edit_; }
@@ -519,6 +558,9 @@ class Compaction {
  // Maximum size of files to build during this compaction.
  uint64_t MaxOutputFileSize() const { return max_output_file_size_; }

+  // Whether compression will be enabled for compaction outputs
+  bool enable_compression() const { return enable_compression_; }
+
  // Is this a trivial compaction that can be implemented by just
  // moving a single input file to the next level (no merging or splitting)
  bool IsTrivialMove() const;
@@ -544,22 +586,30 @@ class Compaction {
  // Return the score that was used to pick this compaction run.
  double score() const { return score_; }

+  // Is this compaction creating a file in the bottom most level?
+  bool BottomMostLevel() { return bottommost_level_; }
+
+  // Does this compaction include all sst files?
+  bool IsFullCompaction() { return is_full_compaction_; }
+
 private:
  friend class Version;
  friend class VersionSet;

-  explicit Compaction(int level, uint64_t target_file_size,
+  explicit Compaction(int level, int out_level, uint64_t target_file_size,
    uint64_t max_grandparent_overlap_bytes, int number_levels,
-    bool seek_compaction = false);
+    bool seek_compaction = false, bool enable_compression = true);

  int level_;
+  int out_level_; // levels to which output files are stored
  uint64_t max_output_file_size_;
-  int64_t maxGrandParentOverlapBytes_;
+  uint64_t maxGrandParentOverlapBytes_;
  Version* input_version_;
  VersionEdit* edit_;
  int number_levels_;

  bool seek_compaction_;
+  bool enable_compression_;

  // Each compaction reads inputs from "level_" and "level_+1"
  std::vector<FileMetaData*> inputs_[2];      // The two sets of inputs
@@ -569,13 +619,16 @@ class Compaction {
  std::vector<FileMetaData*> grandparents_;
  size_t grandparent_index_;  // Index in grandparent_starts_
  bool seen_key_;             // Some output key has been seen
-  int64_t overlapped_bytes_;  // Bytes of overlap between current output
+  uint64_t overlapped_bytes_;  // Bytes of overlap between current output
                              // and grandparent files
  int base_index_;   // index of the file in files_[level_]
  int parent_index_; // index of some file with same range in files_[level_+1]
  double score_;     // score that was used to pick this compaction.

-  // State for implementing IsBaseLevelForKey
+  // Is this compaction creating a file in the bottom most level?
+  bool bottommost_level_;
+  // Does this compaction include all sst files?
+  bool is_full_compaction_;

  // level_ptrs_ holds indices into input_version_->levels_: our state
  // is that we are positioned at one of the file ranges for each
@@ -586,11 +639,12 @@ class Compaction {
  // mark (or clear) all files that are being compacted
  void MarkFilesBeingCompacted(bool);

+  // Initialize whether compaction producing files at the bottommost level
+  void SetupBottomMostLevel(bool isManual);
+
  // In case of compaction error, reset the nextIndex that is used
  // to pick up the next file to be compacted from files_by_size_
  void ResetNextCompactionIndex();
 };

-}  // namespace leveldb
-
-#endif  // STORAGE_LEVELDB_DB_VERSION_SET_H_
+}  // namespace rocksdb
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -10,7 +15,7 @@
 #include "db/log_writer.h"
 #include "util/logging.h"

-namespace leveldb {
+namespace rocksdb {

 Status VersionSet::ReduceNumberOfLevels(int new_levels, port::Mutex* mu) {

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -7,7 +12,7 @@
 #include "util/testharness.h"
 #include "util/testutil.h"

-namespace leveldb {
+namespace rocksdb {

 class FindFileTest {
 public:
@@ -172,8 +177,8 @@ TEST(FindFileTest, OverlappingFiles) {
  ASSERT_TRUE(Overlaps("600", "700"));
 }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.
@@ -14,10 +19,10 @@
 //    len: varint32
 //    data: uint8[len]

-#include "leveldb/write_batch.h"
+#include "rocksdb/write_batch.h"

-#include "leveldb/options.h"
-#include "leveldb/statistics.h"
+#include "rocksdb/options.h"
+#include "rocksdb/statistics.h"
 #include "db/dbformat.h"
 #include "db/db_impl.h"
 #include "db/memtable.h"
@@ -26,7 +31,7 @@
 #include "util/coding.h"
 #include <stdexcept>

-namespace leveldb {
+namespace rocksdb {

 // WriteBatch header has an 8-byte sequence number followed by a 4-byte count.
 static const size_t kHeader = 12;
@@ -43,6 +48,15 @@ void WriteBatch::Handler::Merge(const Slice& key, const Slice& value) {
  throw std::runtime_error("Handler::Merge not implemented!");
 }

+void WriteBatch::Handler::LogData(const Slice& blob) {
+  // If the user has not specified something to do with blobs, then we ignore
+  // them.
+}
+
+bool WriteBatch::Handler::Continue() {
+  return true;
+}
+
 void WriteBatch::Clear() {
  rep_.clear();
  rep_.resize(kHeader);
@@ -59,10 +73,9 @@ Status WriteBatch::Iterate(Handler* handler) const {
  }

  input.remove_prefix(kHeader);
-  Slice key, value;
+  Slice key, value, blob;
  int found = 0;
-  while (!input.empty()) {
-    found++;
+  while (!input.empty() && handler->Continue()) {
    char tag = input[0];
    input.remove_prefix(1);
    switch (tag) {
@@ -70,6 +83,7 @@ Status WriteBatch::Iterate(Handler* handler) const {
        if (GetLengthPrefixedSlice(&input, &key) &&
            GetLengthPrefixedSlice(&input, &value)) {
          handler->Put(key, value);
+          found++;
        } else {
          return Status::Corruption("bad WriteBatch Put");
        }
@@ -77,6 +91,7 @@ Status WriteBatch::Iterate(Handler* handler) const {
      case kTypeDeletion:
        if (GetLengthPrefixedSlice(&input, &key)) {
          handler->Delete(key);
+          found++;
        } else {
          return Status::Corruption("bad WriteBatch Delete");
        }
@@ -85,10 +100,18 @@ Status WriteBatch::Iterate(Handler* handler) const {
        if (GetLengthPrefixedSlice(&input, &key) &&
            GetLengthPrefixedSlice(&input, &value)) {
          handler->Merge(key, value);
+          found++;
        } else {
          return Status::Corruption("bad WriteBatch Merge");
        }
        break;
+      case kTypeLogData:
+        if (GetLengthPrefixedSlice(&input, &blob)) {
+          handler->LogData(blob);
+        } else {
+          return Status::Corruption("bad WriteBatch Blob");
+        }
+        break;
      default:
        return Status::Corruption("unknown WriteBatch tag");
    }
@@ -136,6 +159,10 @@ void WriteBatch::Merge(const Slice& key, const Slice& value) {
  PutLengthPrefixedSlice(&rep_, value);
 }

+void WriteBatch::PutLogData(const Slice& blob) {
+  rep_.push_back(static_cast<char>(kTypeLogData));
+  PutLengthPrefixedSlice(&rep_, blob);
+}

 namespace {
 class MemTableInserter : public WriteBatch::Handler {
@@ -161,7 +188,12 @@ class MemTableInserter : public WriteBatch::Handler {
  }

  virtual void Put(const Slice& key, const Slice& value) {
-    mem_->Add(sequence_, kTypeValue, key, value);
+    if (options_->inplace_update_support
+        && mem_->Update(sequence_, kTypeValue, key, value)) {
+      RecordTick(options_->statistics, NUMBER_KEYS_UPDATED);
+    } else {
+      mem_->Add(sequence_, kTypeValue, key, value);
+    }
    sequence_++;
  }
  virtual void Merge(const Slice& key, const Slice& value) {
@@ -205,4 +237,4 @@ void WriteBatchInternal::Append(WriteBatch* dst, const WriteBatch* src) {
  dst->rep_.append(src->rep_.data() + kHeader, src->rep_.size() - kHeader);
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -1,16 +1,19 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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.

-#ifndef STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
-#define STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
+#pragma once
+#include "rocksdb/types.h"
+#include "rocksdb/write_batch.h"
+#include "rocksdb/db.h"
+#include "rocksdb/options.h"

-#include "leveldb/types.h"
-#include "leveldb/write_batch.h"
-#include "leveldb/db.h"
-#include "leveldb/options.h"
-
-namespace leveldb {
+namespace rocksdb {

 class MemTable;

@@ -45,13 +48,10 @@ class WriteBatchInternal {
  // Drops deletes in batch if filter_del is set to true and
  // db->KeyMayExist returns false
  static Status InsertInto(const WriteBatch* batch, MemTable* memtable,
-                           const Options* opts = nullptr, DB* db = nullptr,
+                           const Options* opts, DB* db = nullptr,
                           const bool filter_del = false);

  static void Append(WriteBatch* dst, const WriteBatch* src);
 };

-}  // namespace leveldb
-
-
-#endif  // STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_
+}  // namespace rocksdb
@@ -1,18 +1,23 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same 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 "leveldb/db.h"
+#include "rocksdb/db.h"

 #include <memory>
-#include "db/skiplistrep.h"
 #include "db/memtable.h"
 #include "db/write_batch_internal.h"
-#include "leveldb/env.h"
+#include "rocksdb/env.h"
+#include "rocksdb/memtablerep.h"
 #include "util/logging.h"
 #include "util/testharness.h"

-namespace leveldb {
+namespace rocksdb {

 static std::string PrintContents(WriteBatch* b) {
  InternalKeyComparator cmp(BytewiseComparator());
@@ -20,7 +25,8 @@ static std::string PrintContents(WriteBatch* b) {
  MemTable* mem = new MemTable(cmp, factory);
  mem->Ref();
  std::string state;
-  Status s = WriteBatchInternal::InsertInto(b, mem);
+  Options options;
+  Status s = WriteBatchInternal::InsertInto(b, mem, &options);
  int count = 0;
  Iterator* iter = mem->NewIterator();
  for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
@@ -50,13 +56,16 @@ static std::string PrintContents(WriteBatch* b) {
        state.append(")");
        count++;
        break;
+      case kTypeLogData:
+        assert(false);
+        break;
    }
    state.append("@");
    state.append(NumberToString(ikey.sequence));
  }
  delete iter;
  if (!s.ok()) {
-    state.append("ParseError()");
+    state.append(s.ToString());
  } else if (count != WriteBatchInternal::Count(b)) {
    state.append("CountMismatch()");
  }
@@ -97,7 +106,7 @@ TEST(WriteBatchTest, Corruption) {
  WriteBatchInternal::SetContents(&batch,
                                  Slice(contents.data(),contents.size()-1));
  ASSERT_EQ("Put(foo, bar)@200"
-            "ParseError()",
+            "Corruption: bad WriteBatch Delete",
            PrintContents(&batch));
 }

@@ -131,8 +140,95 @@ TEST(WriteBatchTest, Append) {
  ASSERT_EQ(4, b1.Count());
 }

-}  // namespace leveldb
+namespace {
+  struct TestHandler : public WriteBatch::Handler {
+    std::string seen;
+    virtual void Put(const Slice& key, const Slice& value) {
+      seen += "Put(" + key.ToString() + ", " + value.ToString() + ")";
+    }
+    virtual void Merge(const Slice& key, const Slice& value) {
+      seen += "Merge(" + key.ToString() + ", " + value.ToString() + ")";
+    }
+    virtual void LogData(const Slice& blob) {
+      seen += "LogData(" + blob.ToString() + ")";
+    }
+    virtual void Delete(const Slice& key) {
+      seen += "Delete(" + key.ToString() + ")";
+    }
+  };
+}
+
+TEST(WriteBatchTest, Blob) {
+  WriteBatch batch;
+  batch.Put(Slice("k1"), Slice("v1"));
+  batch.Put(Slice("k2"), Slice("v2"));
+  batch.Put(Slice("k3"), Slice("v3"));
+  batch.PutLogData(Slice("blob1"));
+  batch.Delete(Slice("k2"));
+  batch.PutLogData(Slice("blob2"));
+  batch.Merge(Slice("foo"), Slice("bar"));
+  ASSERT_EQ(5, batch.Count());
+  ASSERT_EQ("Merge(foo, bar)@4"
+            "Put(k1, v1)@0"
+            "Delete(k2)@3"
+            "Put(k2, v2)@1"
+            "Put(k3, v3)@2",
+            PrintContents(&batch));
+
+  TestHandler handler;
+  batch.Iterate(&handler);
+  ASSERT_EQ(
+            "Put(k1, v1)"
+            "Put(k2, v2)"
+            "Put(k3, v3)"
+            "LogData(blob1)"
+            "Delete(k2)"
+            "LogData(blob2)"
+            "Merge(foo, bar)",
+            handler.seen);
+}
+
+TEST(WriteBatchTest, Continue) {
+  WriteBatch batch;
+
+  struct Handler : public TestHandler {
+    int num_seen = 0;
+    virtual void Put(const Slice& key, const Slice& value) {
+      ++num_seen;
+      TestHandler::Put(key, value);
+    }
+    virtual void Merge(const Slice& key, const Slice& value) {
+      ++num_seen;
+      TestHandler::Merge(key, value);
+    }
+    virtual void LogData(const Slice& blob) {
+      ++num_seen;
+      TestHandler::LogData(blob);
+    }
+    virtual void Delete(const Slice& key) {
+      ++num_seen;
+      TestHandler::Delete(key);
+    }
+    virtual bool Continue() override {
+      return num_seen < 3;
+    }
+  } handler;
+
+  batch.Put(Slice("k1"), Slice("v1"));
+  batch.PutLogData(Slice("blob1"));
+  batch.Delete(Slice("k1"));
+  batch.PutLogData(Slice("blob2"));
+  batch.Merge(Slice("foo"), Slice("bar"));
+  batch.Iterate(&handler);
+  ASSERT_EQ(
+            "Put(k1, v1)"
+            "LogData(blob1)"
+            "Delete(k1)",
+            handler.seen);
+}
+
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -111,7 +111,7 @@ static void WalCheckpoint(sqlite3* db_) {
  }
 }

-namespace leveldb {
+namespace rocksdb {

 // Helper for quickly generating random data.
 namespace {
@@ -664,7 +664,7 @@ class Benchmark {

 };

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
  std::string default_db_path;
@@ -672,7 +672,7 @@ int main(int argc, char** argv) {
    double d;
    int n;
    char junk;
-    if (leveldb::Slice(argv[i]).starts_with("--benchmarks=")) {
+    if (rocksdb::Slice(argv[i]).starts_with("--benchmarks=")) {
      FLAGS_benchmarks = argv[i] + strlen("--benchmarks=");
    } else if (sscanf(argv[i], "--histogram=%d%c", &n, &junk) == 1 &&
               (n == 0 || n == 1)) {
@@ -688,7 +688,7 @@ int main(int argc, char** argv) {
      FLAGS_reads = n;
    } else if (sscanf(argv[i], "--value_size=%d%c", &n, &junk) == 1) {
      FLAGS_value_size = n;
-    } else if (leveldb::Slice(argv[i]) == leveldb::Slice("--no_transaction")) {
+    } else if (rocksdb::Slice(argv[i]) == rocksdb::Slice("--no_transaction")) {
      FLAGS_transaction = false;
    } else if (sscanf(argv[i], "--page_size=%d%c", &n, &junk) == 1) {
      FLAGS_page_size = n;
@@ -707,12 +707,12 @@ int main(int argc, char** argv) {

  // Choose a location for the test database if none given with --db=<path>
  if (FLAGS_db == NULL) {
-      leveldb::Env::Default()->GetTestDirectory(&default_db_path);
+      rocksdb::Env::Default()->GetTestDirectory(&default_db_path);
      default_db_path += "/dbbench";
      FLAGS_db = default_db_path.c_str();
  }

-  leveldb::Benchmark benchmark;
+  rocksdb::Benchmark benchmark;
  benchmark.Run();
  return 0;
 }
@@ -80,7 +80,7 @@ static void DBSynchronize(kyotocabinet::TreeDB* db_)
  }
 }

-namespace leveldb {
+namespace rocksdb {

 // Helper for quickly generating random data.
 namespace {
@@ -479,7 +479,7 @@ class Benchmark {
  }
 };

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
  std::string default_db_path;
@@ -487,7 +487,7 @@ int main(int argc, char** argv) {
    double d;
    int n;
    char junk;
-    if (leveldb::Slice(argv[i]).starts_with("--benchmarks=")) {
+    if (rocksdb::Slice(argv[i]).starts_with("--benchmarks=")) {
      FLAGS_benchmarks = argv[i] + strlen("--benchmarks=");
    } else if (sscanf(argv[i], "--compression_ratio=%lf%c", &d, &junk) == 1) {
      FLAGS_compression_ratio = d;
@@ -517,12 +517,12 @@ int main(int argc, char** argv) {

  // Choose a location for the test database if none given with --db=<path>
  if (FLAGS_db == NULL) {
-      leveldb::Env::Default()->GetTestDirectory(&default_db_path);
+      rocksdb::Env::Default()->GetTestDirectory(&default_db_path);
      default_db_path += "/dbbench";
      FLAGS_db = default_db_path.c_str();
  }

-  leveldb::Benchmark benchmark;
+  rocksdb::Benchmark benchmark;
  benchmark.Run();
  return 0;
 }
@@ -25,27 +25,27 @@ creating it if necessary:
  #include &lt;assert&gt;
  #include "leveldb/db.h"

-  leveldb::DB* db;
-  leveldb::Options options;
+  rocksdb::DB* db;
+  rocksdb::Options options;
  options.create_if_missing = true;
-  leveldb::Status status = leveldb::DB::Open(options, "/tmp/testdb", &amp;db);
+  rocksdb::Status status = rocksdb::DB::Open(options, "/tmp/testdb", &amp;db);
  assert(status.ok());
  ...
 </pre>
 If you want to raise an error if the database already exists, add
-the following line before the <code>leveldb::DB::Open</code> call:
+the following line before the <code>rocksdb::DB::Open</code> call:
 <pre>
  options.error_if_exists = true;
 </pre>
 <h1>Status</h1>
 <p>
-You may have noticed the <code>leveldb::Status</code> type above.  Values of this
+You may have noticed the <code>rocksdb::Status</code> type above.  Values of this
 type are returned by most functions in <code>leveldb</code> that may encounter an
 error.  You can check if such a result is ok, and also print an
 associated error message:
 <p>
 <pre>
-   leveldb::Status s = ...;
+   rocksdb::Status s = ...;
   if (!s.ok()) cerr &lt;&lt; s.ToString() &lt;&lt; endl;
 </pre>
 <h1>Closing A Database</h1>
@@ -65,9 +65,9 @@ modify/query the database.  For example, the following code
 moves the value stored under key1 to key2.
 <pre>
  std::string value;
-  leveldb::Status s = db-&gt;Get(leveldb::ReadOptions(), key1, &amp;value);
-  if (s.ok()) s = db-&gt;Put(leveldb::WriteOptions(), key2, value);
-  if (s.ok()) s = db-&gt;Delete(leveldb::WriteOptions(), key1);
+  rocksdb::Status s = db-&gt;Get(rocksdb::ReadOptions(), key1, &amp;value);
+  if (s.ok()) s = db-&gt;Put(rocksdb::WriteOptions(), key2, value);
+  if (s.ok()) s = db-&gt;Delete(rocksdb::WriteOptions(), key1);
 </pre>

 <h1>Atomic Updates</h1>
@@ -81,12 +81,12 @@ atomically apply a set of updates:
  #include "leveldb/write_batch.h"
  ...
  std::string value;
-  leveldb::Status s = db-&gt;Get(leveldb::ReadOptions(), key1, &amp;value);
+  rocksdb::Status s = db-&gt;Get(rocksdb::ReadOptions(), key1, &amp;value);
  if (s.ok()) {
-    leveldb::WriteBatch batch;
+    rocksdb::WriteBatch batch;
    batch.Delete(key1);
    batch.Put(key2, value);
-    s = db-&gt;Write(leveldb::WriteOptions(), &amp;batch);
+    s = db-&gt;Write(rocksdb::WriteOptions(), &amp;batch);
  }
 </pre>
 The <code>WriteBatch</code> holds a sequence of edits to be made to the database,
@@ -109,7 +109,7 @@ persistent storage.  (On Posix systems, this is implemented by calling
 either <code>fsync(...)</code> or <code>fdatasync(...)</code> or
 <code>msync(..., MS_SYNC)</code> before the write operation returns.)
 <pre>
-  leveldb::WriteOptions write_options;
+  rocksdb::WriteOptions write_options;
  write_options.sync = true;
  db-&gt;Put(write_options, ...);
 </pre>
@@ -144,7 +144,7 @@ the batch.
 A database may only be opened by one process at a time.
 The <code>leveldb</code> implementation acquires a lock from the
 operating system to prevent misuse.  Within a single process, the
-same <code>leveldb::DB</code> object may be safely shared by multiple
+same <code>rocksdb::DB</code> object may be safely shared by multiple
 concurrent threads.  I.e., different threads may write into or fetch
 iterators or call <code>Get</code> on the same database without any
 external synchronization (the leveldb implementation will
@@ -160,7 +160,7 @@ The following example demonstrates how to print all key,value pairs
 in a database.
 <p>
 <pre>
-  leveldb::Iterator* it = db-&gt;NewIterator(leveldb::ReadOptions());
+  rocksdb::Iterator* it = db-&gt;NewIterator(rocksdb::ReadOptions());
  for (it-&gt;SeekToFirst(); it-&gt;Valid(); it-&gt;Next()) {
    cout &lt;&lt; it-&gt;key().ToString() &lt;&lt; ": "  &lt;&lt; it-&gt;value().ToString() &lt;&lt; endl;
  }
@@ -196,10 +196,10 @@ implicit snapshot of the current state.
 Snapshots are created by the DB::GetSnapshot() method:
 <p>
 <pre>
-  leveldb::ReadOptions options;
+  rocksdb::ReadOptions options;
  options.snapshot = db-&gt;GetSnapshot();
  ... apply some updates to db ...
-  leveldb::Iterator* iter = db-&gt;NewIterator(options);
+  rocksdb::Iterator* iter = db-&gt;NewIterator(options);
  ... read using iter to view the state when the snapshot was created ...
  delete iter;
  db-&gt;ReleaseSnapshot(options.snapshot);
@@ -211,7 +211,7 @@ support reading as of that snapshot.
 <h1>Slice</h1>
 <p>
 The return value of the <code>it->key()</code> and <code>it->value()</code> calls above
-are instances of the <code>leveldb::Slice</code> type.  <code>Slice</code> is a simple
+are instances of the <code>rocksdb::Slice</code> type.  <code>Slice</code> is a simple
 structure that contains a length and a pointer to an external byte
 array.  Returning a <code>Slice</code> is a cheaper alternative to returning a
 <code>std::string</code> since we do not need to copy potentially large keys and
@@ -223,10 +223,10 @@ C++ strings and null-terminated C-style strings can be easily converted
 to a Slice:
 <p>
 <pre>
-   leveldb::Slice s1 = "hello";
+   rocksdb::Slice s1 = "hello";

   std::string str("world");
-   leveldb::Slice s2 = str;
+   rocksdb::Slice s2 = str;
 </pre>
 A Slice can be easily converted back to a C++ string:
 <pre>
@@ -238,7 +238,7 @@ the external byte array into which the Slice points remains live while
 the Slice is in use.  For example, the following is buggy:
 <p>
 <pre>
-   leveldb::Slice slice;
+   rocksdb::Slice slice;
   if (...) {
     std::string str = ...;
     slice = str;
@@ -255,16 +255,16 @@ which orders bytes lexicographically.  You can however supply a custom
 comparator when opening a database.  For example, suppose each
 database key consists of two numbers and we should sort by the first
 number, breaking ties by the second number.  First, define a proper
-subclass of <code>leveldb::Comparator</code> that expresses these rules:
+subclass of <code>rocksdb::Comparator</code> that expresses these rules:
 <p>
 <pre>
-  class TwoPartComparator : public leveldb::Comparator {
+  class TwoPartComparator : public rocksdb::Comparator {
   public:
    // Three-way comparison function:
    //   if a &lt; b: negative result
    //   if a &gt; b: positive result
    //   else: zero result
-    int Compare(const leveldb::Slice&amp; a, const leveldb::Slice&amp; b) const {
+    int Compare(const rocksdb::Slice&amp; a, const rocksdb::Slice&amp; b) const {
      int a1, a2, b1, b2;
      ParseKey(a, &amp;a1, &amp;a2);
      ParseKey(b, &amp;b1, &amp;b2);
@@ -277,7 +277,7 @@ subclass of <code>leveldb::Comparator</code> that expresses these rules:

    // Ignore the following methods for now:
    const char* Name() const { return "TwoPartComparator"; }
-    void FindShortestSeparator(std::string*, const leveldb::Slice&amp;) const { }
+    void FindShortestSeparator(std::string*, const rocksdb::Slice&amp;) const { }
    void FindShortSuccessor(std::string*) const { }
  };
 </pre>
@@ -285,18 +285,18 @@ Now create a database using this custom comparator:
 <p>
 <pre>
  TwoPartComparator cmp;
-  leveldb::DB* db;
-  leveldb::Options options;
+  rocksdb::DB* db;
+  rocksdb::Options options;
  options.create_if_missing = true;
  options.comparator = &amp;cmp;
-  leveldb::Status status = leveldb::DB::Open(options, "/tmp/testdb", &amp;db);
+  rocksdb::Status status = rocksdb::DB::Open(options, "/tmp/testdb", &amp;db);
  ...
 </pre>
 <h2>Backwards compatibility</h2>
 <p>
 The result of the comparator's <code>Name</code> method is attached to the
 database when it is created, and is checked on every subsequent
-database open.  If the name changes, the <code>leveldb::DB::Open</code> call will
+database open.  If the name changes, the <code>rocksdb::DB::Open</code> call will
 fail.  Therefore, change the name if and only if the new key format
 and comparison function are incompatible with existing databases, and
 it is ok to discard the contents of all existing databases.
@@ -339,9 +339,9 @@ compression entirely, but should only do so if benchmarks show a
 performance improvement:
 <p>
 <pre>
-  leveldb::Options options;
-  options.compression = leveldb::kNoCompression;
-  ... leveldb::DB::Open(options, name, ...) ....
+  rocksdb::Options options;
+  options.compression = rocksdb::kNoCompression;
+  ... rocksdb::DB::Open(options, name, ...) ....
 </pre>
 <h2>Cache</h2>
 <p>
@@ -353,10 +353,10 @@ uncompressed block contents.
 <pre>
  #include "leveldb/cache.h"

-  leveldb::Options options;
-  options.cache = leveldb::NewLRUCache(100 * 1048576);  // 100MB cache
-  leveldb::DB* db;
-  leveldb::DB::Open(options, name, &db);
+  rocksdb::Options options;
+  options.cache = rocksdb::NewLRUCache(100 * 1048576);  // 100MB cache
+  rocksdb::DB* db;
+  rocksdb::DB::Open(options, name, &db);
  ... use the db ...
  delete db
  delete options.cache;
@@ -373,9 +373,9 @@ displacing most of the cached contents.  A per-iterator option can be
 used to achieve this:
 <p>
 <pre>
-  leveldb::ReadOptions options;
+  rocksdb::ReadOptions options;
  options.fill_cache = false;
-  leveldb::Iterator* it = db-&gt;NewIterator(options);
+  rocksdb::Iterator* it = db-&gt;NewIterator(options);
  for (it-&gt;SeekToFirst(); it-&gt;Valid(); it-&gt;Next()) {
    ...
  }
@@ -407,10 +407,10 @@ a single <code>Get()</code> call may involve multiple reads from disk.
 The optional <code>FilterPolicy</code> mechanism can be used to reduce
 the number of disk reads substantially.
 <pre>
-   leveldb::Options options;
+   rocksdb::Options options;
   options.filter_policy = NewBloomFilter(10);
-   leveldb::DB* db;
-   leveldb::DB::Open(options, "/tmp/testdb", &amp;db);
+   rocksdb::DB* db;
+   rocksdb::DB::Open(options, "/tmp/testdb", &amp;db);
   ... use the database ...
   delete db;
   delete options.filter_policy;
@@ -434,7 +434,7 @@ consider a comparator that ignores trailing spaces when comparing keys.
 Instead, the application should provide a custom filter policy that
 also ignores trailing spaces.  For example:
 <pre>
-  class CustomFilterPolicy : public leveldb::FilterPolicy {
+  class CustomFilterPolicy : public rocksdb::FilterPolicy {
   private:
    FilterPolicy* builtin_policy_;
   public:
@@ -484,7 +484,7 @@ checksums are verified:
  parts of its persistent storage have been corrupted.
 <p>
  If a database is corrupted (perhaps it cannot be opened when
-  paranoid checking is turned on), the <code>leveldb::RepairDB</code> function
+  paranoid checking is turned on), the <code>rocksdb::RepairDB</code> function
  may be used to recover as much of the data as possible
 <p>
 </ul>
@@ -494,11 +494,11 @@ The <code>GetApproximateSizes</code> method can used to get the approximate
 number of bytes of file system space used by one or more key ranges.
 <p>
 <pre>
-   leveldb::Range ranges[2];
-   ranges[0] = leveldb::Range("a", "c");
-   ranges[1] = leveldb::Range("x", "z");
+   rocksdb::Range ranges[2];
+   ranges[0] = rocksdb::Range("a", "c");
+   ranges[1] = rocksdb::Range("x", "z");
   uint64_t sizes[2];
-   leveldb::Status s = db-&gt;GetApproximateSizes(ranges, 2, sizes);
+   rocksdb::Status s = db-&gt;GetApproximateSizes(ranges, 2, sizes);
 </pre>
 The preceding call will set <code>sizes[0]</code> to the approximate number of
 bytes of file system space used by the key range <code>[a..c)</code> and
@@ -508,21 +508,21 @@ bytes of file system space used by the key range <code>[a..c)</code> and
 <h1>Environment</h1>
 <p>
 All file operations (and other operating system calls) issued by the
-<code>leveldb</code> implementation are routed through a <code>leveldb::Env</code> object.
+<code>leveldb</code> implementation are routed through a <code>rocksdb::Env</code> object.
 Sophisticated clients may wish to provide their own <code>Env</code>
 implementation to get better control.  For example, an application may
 introduce artificial delays in the file IO paths to limit the impact
 of <code>leveldb</code> on other activities in the system.
 <p>
 <pre>
-  class SlowEnv : public leveldb::Env {
+  class SlowEnv : public rocksdb::Env {
    .. implementation of the Env interface ...
  };

  SlowEnv env;
-  leveldb::Options options;
+  rocksdb::Options options;
  options.env = &amp;env;
-  Status s = leveldb::DB::Open(options, ...);
+  Status s = rocksdb::DB::Open(options, ...);
 </pre>
 <h1>Porting</h1>
 <p>
@@ -531,7 +531,7 @@ specific implementations of the types/methods/functions exported by
 <code>leveldb/port/port.h</code>.  See <code>leveldb/port/port_example.h</code> for more
 details.
 <p>
-In addition, the new platform may need a new default <code>leveldb::Env</code>
+In addition, the new platform may need a new default <code>rocksdb::Env</code>
 implementation.  See <code>leveldb/util/env_posix.h</code> for an example.

 <h1>Other Information</h1>
@@ -1,2 +0,0 @@
-ar: creating libmemenv.a
-ar: creating libleveldb.a
@@ -1,4 +1,4 @@
-This directory contains the hdfs extensions needed to make leveldb store
+This directory contains the hdfs extensions needed to make rocksdb store
 files in HDFS.

 The hdfs.h file is copied from the Apache Hadoop 1.0 source code. 
@@ -7,12 +7,12 @@ It defines the libhdfs library
 data in HDFS.  The libhdfs.a is copied from the Apache Hadoop 1.0 build. 
 It implements the API defined in hdfs.h. If your hadoop cluster is running
 a different hadoop release, then install these two files manually from your
-hadoop distribution and then recompile leveldb.
+hadoop distribution and then recompile rocksdb.

-The env_hdfs.h file defines the leveldb objects that are needed to talk to an
+The env_hdfs.h file defines the rocksdb objects that are needed to talk to an
 underlying filesystem. 

-If you want to compile leveldb with hdfs support, please set the following
+If you want to compile rocksdb with hdfs support, please set the following
 enviroment variables appropriately:
   USE_HDFS=1
   JAVA_HOME=/usr/local/jdk-6u22-64
@@ -1,37 +1,22 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-// Copyright (c) 2012 Facebook. All rights reserved.
-
-#ifndef LEVELDB_HDFS_FILE_H
-#define LEVELDB_HDFS_FILE_H
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//

+#pragma once
 #include <algorithm>
 #include <stdio.h>
 #include <sys/time.h>
 #include <time.h>
 #include <iostream>
-#include "leveldb/env.h"
-#include "leveldb/status.h"
+#include "rocksdb/env.h"
+#include "rocksdb/status.h"

 #ifdef USE_HDFS
 #include "hdfs/hdfs.h"

-namespace leveldb {
+namespace rocksdb {

 static const std::string kProto = "hdfs://";
 static const std::string pathsep = "/";
@@ -55,7 +40,7 @@ private:
 };

 //
-// The HDFS environment for leveldb. This class overrides all the
+// The HDFS environment for rocksdb. This class overrides all the
 // file/dir access methods and delegates the thread-mgmt methods to the
 // default posix environment.
 //
@@ -81,6 +66,10 @@ class HdfsEnv : public Env {
  virtual Status NewWritableFile(const std::string& fname,
                                 WritableFile** result);

+  virtual Status NewRandomRWFile(const std::string& fname,
+                                 unique_ptr<RandomRWFile>* result,
+                                 const EnvOptions& options);
+
  virtual bool FileExists(const std::string& fname);

  virtual Status GetChildren(const std::string& path,
@@ -107,8 +96,9 @@ class HdfsEnv : public Env {

  virtual Status NewLogger(const std::string& fname, Logger** result);

-  virtual void Schedule( void (*function)(void* arg), void* arg) {
-    posixEnv->Schedule(function, arg);
+  virtual void Schedule(void (*function)(void* arg), void* arg,
+                        Priority pri = LOW) {
+    posixEnv->Schedule(function, arg, pri);
  }

  virtual void StartThread(void (*function)(void* arg), void* arg) {
@@ -140,8 +130,8 @@ class HdfsEnv : public Env {
    return posixEnv->GetAbsolutePath(db_path, output_path);
  }

-  virtual void SetBackgroundThreads(int number) {
-    posixEnv->SetBackgroundThreads(number);
+  virtual void SetBackgroundThreads(int number, Priority pri = LOW) {
+    posixEnv->SetBackgroundThreads(number, pri);
  }

  virtual std::string TimeToString(uint64_t number) {
@@ -213,12 +203,12 @@ class HdfsEnv : public Env {
  }
 };

-}  // namespace leveldb
+}  // namespace rocksdb

 #else // USE_HDFS


-namespace leveldb {
+namespace rocksdb {

 static const Status notsup;

@@ -226,7 +216,7 @@ class HdfsEnv : public Env {

 public:
  HdfsEnv(const std::string& fsname) {
-    fprintf(stderr, "You have not build leveldb with HDFS support\n");
+    fprintf(stderr, "You have not build rocksdb with HDFS support\n");
    fprintf(stderr, "Please see hdfs/README for details\n");
    throw new std::exception();
  }
@@ -250,6 +240,12 @@ class HdfsEnv : public Env {
    return notsup;
  }

+  virtual Status NewRandomRWFile(const std::string& fname,
+                                 unique_ptr<RandomRWFile>* result,
+                                 const EnvOptions& options) {
+    return notsup;
+  }
+
  virtual bool FileExists(const std::string& fname){return false;}

  virtual Status GetChildren(const std::string& path,
@@ -279,7 +275,8 @@ class HdfsEnv : public Env {
  virtual Status NewLogger(const std::string& fname,
                           shared_ptr<Logger>* result){return notsup;}

-  virtual void Schedule( void (*function)(void* arg), void* arg) {}
+  virtual void Schedule(void (*function)(void* arg), void* arg,
+                        Priority pri = LOW) {}

  virtual void StartThread(void (*function)(void* arg), void* arg) {}

@@ -296,12 +293,10 @@ class HdfsEnv : public Env {
  virtual Status GetAbsolutePath(const std::string& db_path,
      std::string* outputpath) {return notsup;}

-  virtual void SetBackgroundThreads(int number) {}
+  virtual void SetBackgroundThreads(int number, Priority pri = LOW) {}

  virtual std::string TimeToString(uint64_t number) { return "";}
 };
 }

 #endif // USE_HDFS
-
-#endif // LEVELDB_HDFS_FILE_H
@@ -1,21 +1,8 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #ifndef LIBHDFS_HDFS_H
 #define LIBHDFS_HDFS_H

@@ -4,8 +4,8 @@

 #include "helpers/memenv/memenv.h"

-#include "leveldb/env.h"
-#include "leveldb/status.h"
+#include "rocksdb/env.h"
+#include "rocksdb/status.h"
 #include "port/port.h"
 #include "util/mutexlock.h"
 #include <map>
@@ -13,7 +13,7 @@
 #include <string>
 #include <vector>

-namespace leveldb {
+namespace rocksdb {

 namespace {

@@ -383,4 +383,4 @@ Env* NewMemEnv(Env* base_env) {
  return new InMemoryEnv(base_env);
 }

-}  // namespace leveldb
+}  // namespace rocksdb
@@ -2,10 +2,9 @@
 // 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.

-#ifndef STORAGE_LEVELDB_HELPERS_MEMENV_MEMENV_H_
-#define STORAGE_LEVELDB_HELPERS_MEMENV_MEMENV_H_
-
-namespace leveldb {
+#ifndef STORAGE_ROCKSDB_HELPERS_MEMENV_MEMENV_H_
+#define STORAGE_ROCKSDB_HELPERS_MEMENV_MEMENV_H_
+namespace rocksdb {

 class Env;

@@ -15,6 +14,6 @@ class Env;
 // *base_env must remain live while the result is in use.
 Env* NewMemEnv(Env* base_env);

-}  // namespace leveldb
+}  // namespace rocksdb

-#endif  // STORAGE_LEVELDB_HELPERS_MEMENV_MEMENV_H_
+#endif  // STORAGE_ROCKSDB_HELPERS_MEMENV_MEMENV_H_
@@ -5,14 +5,14 @@
 #include "helpers/memenv/memenv.h"

 #include "db/db_impl.h"
-#include "leveldb/db.h"
-#include "leveldb/env.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
 #include "util/testharness.h"
 #include <memory>
 #include <string>
 #include <vector>

-namespace leveldb {
+namespace rocksdb {

 class MemEnvTest {
 public:
@@ -215,7 +215,7 @@ TEST(MemEnvTest, DBTest) {
  delete iterator;

  DBImpl* dbi = reinterpret_cast<DBImpl*>(db);
-  ASSERT_OK(dbi->TEST_CompactMemTable());
+  ASSERT_OK(dbi->TEST_FlushMemTable());

  for (size_t i = 0; i < 3; ++i) {
    std::string res;
@@ -226,8 +226,8 @@ TEST(MemEnvTest, DBTest) {
  delete db;
 }

-}  // namespace leveldb
+}  // namespace rocksdb

 int main(int argc, char** argv) {
-  return leveldb::test::RunAllTests();
+  return rocksdb::test::RunAllTests();
 }
@@ -1,14 +0,0 @@
-// Copyright 2008-present Facebook. All Rights Reserved.
-#ifndef STORAGE_LEVELDB_INCLUDE_LDB_TOOL_H
-#define STORAGE_LEVELDB_INCLUDE_LDB_TOOL_H
-#include "leveldb/options.h"
-
-namespace leveldb {
-
-class LDBTool {
- public:
-  void Run(int argc, char** argv, Options = Options());
-};
-
-} // namespace leveldb
-#endif // STORAGE_LEVELDB_INCLUDE_LDB_TOOL_H
@@ -1,88 +0,0 @@
-// This file contains the interface that must be implemented by any collection
-// to be used as the backing store for a MemTable. Such a collection must
-// satisfy the following properties:
-//  (1) It does not store duplicate items.
-//  (2) It uses MemTableRep::KeyComparator to compare items for iteration and
-//     equality.
-//  (3) It can be accessed concurrently by multiple readers but need not support
-//      concurrent writes.
-//  (4) Items are never deleted.
-// The liberal use of assertions is encouraged to enforce (1).
-
-#ifndef STORAGE_LEVELDB_DB_TABLE_H_
-#define STORAGE_LEVELDB_DB_TABLE_H_
-
-#include <memory>
-#include "leveldb/arena.h"
-
-namespace leveldb {
-
-class MemTableRep {
- public:
-  // KeyComparator(a, b) returns a negative value if a is less than b, 0 if they
-  // are equal, and a positive value if b is greater than a
-  class KeyComparator {
-  public:
-    virtual int operator()(const char* a, const char* b) const = 0;
-    virtual ~KeyComparator() { }
-  };
-
-  // Insert key into the collection. (The caller will pack key and value into a
-  // single buffer and pass that in as the parameter to Insert)
-  // REQUIRES: nothing that compares equal to key is currently in the
-  // collection.
-  virtual void Insert(const char* key) = 0;
-
-  // Returns true iff an entry that compares equal to key is in the collection.
-  virtual bool Contains(const char* key) const = 0;
-
-  virtual ~MemTableRep() { }
-
-  // Iteration over the contents of a skip collection
-  class Iterator {
-   public:
-    // Initialize an iterator over the specified collection.
-    // The returned iterator is not valid.
-    // explicit Iterator(const MemTableRep* collection);
-    virtual ~Iterator() { };
-
-    // Returns true iff the iterator is positioned at a valid node.
-    virtual bool Valid() const = 0;
-
-    // Returns the key at the current position.
-    // REQUIRES: Valid()
-    virtual const char* key() const = 0;
-
-    // Advances to the next position.
-    // REQUIRES: Valid()
-    virtual void Next() = 0;
-
-    // Advances to the previous position.
-    // REQUIRES: Valid()
-    virtual void Prev() = 0;
-
-    // Advance to the first entry with a key >= target
-    virtual void Seek(const char* target) = 0;
-
-    // Position at the first entry in collection.
-    // Final state of iterator is Valid() iff collection is not empty.
-    virtual void SeekToFirst() = 0;
-
-    // Position at the last entry in collection.
-    // Final state of iterator is Valid() iff collection is not empty.
-    virtual void SeekToLast() = 0;
-  };
-
-  virtual std::shared_ptr<Iterator> GetIterator() = 0;
-};
-
-class MemTableRepFactory {
- public:
-  virtual ~MemTableRepFactory() { };
-  virtual std::shared_ptr<MemTableRep> CreateMemTableRep(
-    MemTableRep::KeyComparator&, Arena* arena) = 0;
-};
-
-}
-
-#endif // STORAGE_LEVELDB_DB_TABLE_H_
@@ -1,42 +0,0 @@
-// Copyright 2008-present Facebook. All Rights Reserved.
-#ifndef STORAGE_LEVELDB_INCLUDE_TRANSACTION_LOG_ITERATOR_H_
-#define STORAGE_LEVELDB_INCLUDE_TRANSACTION_LOG_ITERATOR_H_
-
-#include "leveldb/status.h"
-#include "leveldb/write_batch.h"
-
-namespace leveldb {
-
-
-struct BatchResult {
-  SequenceNumber sequence;
-  std::unique_ptr<WriteBatch> writeBatchPtr;
-};
-
-//  A TransactionLogIterator is used to iterate over the Transaction's in a db.
-class TransactionLogIterator {
- public:
-  TransactionLogIterator() {}
-  virtual ~TransactionLogIterator() {}
-
-  // An iterator is either positioned at a WriteBatch or not valid.
-  // This method returns true if the iterator is valid.
-  // Can read data from a valid iterator.
-  virtual bool Valid() = 0;
-
-  // Moves the iterator to the next WriteBatch.
-  // REQUIRES: Valid() to be true.
-  virtual void Next() = 0;
-
-  // Return's ok if the iterator is valid.
-  // Return the Error when something has gone wrong.
-  virtual Status status() = 0;
-
-  // If valid return's the current write_batch and the sequence number of the
-  // latest transaction contained in the batch.
-  // ONLY use if Valid() is true and status() is OK.
-  virtual BatchResult GetBatch() = 0;
-};
-} //  namespace leveldb
-
-#endif  // STORAGE_LEVELDB_INCLUDE_TRANSACTION_LOG_ITERATOR_H_
@@ -1,14 +0,0 @@
-#ifndef STORAGE_LEVELDB_INCLUDE_TYPES_H_
-#define STORAGE_LEVELDB_INCLUDE_TYPES_H_
-
-#include <stdint.h>
-
-namespace leveldb {
-
-// Define all public custom types here.
-
-//  Represents a sequence number in a WAL file.
-typedef uint64_t SequenceNumber;
-
-}  //  namespace leveldb
-#endif //  STORAGE_LEVELDB_INCLUDE_TYPES_H_
@@ -5,10 +5,13 @@
 // Arena class defines memory allocation methods. It's used by memtable and
 // skiplist.

-#ifndef STORAGE_LEVELDB_INCLUDE_ARENA_H_
-#define STORAGE_LEVELDB_INCLUDE_ARENA_H_
+#ifndef STORAGE_ROCKSDB_INCLUDE_ARENA_H_
+#define STORAGE_ROCKSDB_INCLUDE_ARENA_H_

-namespace leveldb {
+#include <limits>
+#include <memory>
+
+namespace rocksdb {

 class Arena {
 public:
@@ -33,6 +36,6 @@ class Arena {
  void operator=(const Arena&);
 };

-}  // namespace leveldb
+}  // namespace rocksdb

-#endif  // STORAGE_LEVELDB_INCLUDE_ARENA_H_
+#endif  // STORAGE_ROCKSDB_INCLUDE_ARENA_H_