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HISTORY.md

@@ -1,3 +1,4 @@
+test
 # Rocksdb Change Log
 ## Unreleased
 ### Bug Fixes

db/corruption_test.cc

@@ -369,6 +369,12 @@ TEST_F(CorruptionTest, VerifyChecksumReadahead) {
   ASSERT_GE(senv.random_read_counter_.Read(), 213);
   ASSERT_LE(senv.random_read_counter_.Read(), 447);
 
+  // Test readahead shouldn't break mmap mode (where it should be
+  // disabled).
+  options.allow_mmap_reads = true;
+  Reopen(&options);
+  ASSERT_OK(dbi->VerifyChecksum(ro));
+
   CloseDb();
 }
 

table/block_based/block_based_table_reader.cc

@@ -3750,8 +3750,11 @@ Status BlockBasedTable::VerifyChecksumInBlocks(
   size_t readahead_size = (read_options.readahead_size != 0)
                               ? read_options.readahead_size
                               : kMaxAutoReadaheadSize;
+  // FilePrefetchBuffer doesn't work in mmap mode and readahead is not
+  // needed there.
   FilePrefetchBuffer prefetch_buffer(rep_->file.get(), readahead_size,
-                                     readahead_size);
+                                     readahead_size,
+                                     !rep_->ioptions.allow_mmap_reads);
 
   for (index_iter->SeekToFirst(); index_iter->Valid(); index_iter->Next()) {
     s = index_iter->status();