mirror of
https://github.com/facebook/rocksdb.git
synced 2024-11-26 07:30:54 +00:00
f6d7ec1d02
Summary: Apparently setting total_order_seek=true for DB::Get was intended to allow accurate read semantics if the current prefix extractor doesn't match what was used to generate SST files on disk. But since prefix_extractor was made a mutable option in 5.14.0, we have been able to detect this case and provide the correct semantics regardless of the total_order_seek option. Since that time, the option has only made Get() slower in a reasonably common case: prefix_extractor unchanged and whole_key_filtering=false. So this change primarily removes unnecessary effect of total_order_seek on Get. Also cleans up some related comments. Also adds a -total_order_seek option to db_bench and canonicalizes handling of ReadOptions in db_bench so that command line options have the expected association with library features. (There is potential for change in regression test behavior, but the old behavior is likely indefensible, or some other inconsistency would need to be fixed.) TODO in follow-up work: there should be no reason for Get() to depend on current prefix extractor at all. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9427 Test Plan: Unit tests updated. Performance (using db_bench update) Create DB with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12 -whole_key_filtering=0` Test with and without `-total_order_seek` on `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=readrandom -num=10000000 -duration=40 -disable_wal=1 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12` Before this change, total_order_seek=false: 25188 ops/sec Before this change, total_order_seek=true: 1222 ops/sec (~20x slower) After this change, total_order_seek=false: 24570 ops/sec After this change, total_order_seek=true: 25012 ops/sec (indistinguishable) Reviewed By: siying Differential Revision: D33753458 Pulled By: pdillinger fbshipit-source-id: bf892f34907a5e407d9c40bd4d42f0adbcbe0014 |
||
|---|---|---|
| .. | ||
| advisor | ||
| block_cache_analyzer | ||
| dump | ||
| analyze_txn_stress_test.sh | ||
| auto_sanity_test.sh | ||
| backup_db.sh | ||
| benchmark.sh | ||
| benchmark_leveldb.sh | ||
| blob_dump.cc | ||
| check_all_python.py | ||
| check_format_compatible.sh | ||
| CMakeLists.txt | ||
| db_bench.cc | ||
| db_bench_tool.cc | ||
| db_bench_tool_test.cc | ||
| db_crashtest.py | ||
| db_repl_stress.cc | ||
| db_sanity_test.cc | ||
| dbench_monitor | ||
| Dockerfile | ||
| generate_random_db.sh | ||
| ingest_external_sst.sh | ||
| io_tracer_parser.cc | ||
| io_tracer_parser_test.cc | ||
| io_tracer_parser_tool.cc | ||
| io_tracer_parser_tool.h | ||
| ldb.cc | ||
| ldb_cmd.cc | ||
| ldb_cmd_impl.h | ||
| ldb_cmd_test.cc | ||
| ldb_test.py | ||
| ldb_tool.cc | ||
| pflag | ||
| reduce_levels_test.cc | ||
| regression_test.sh | ||
| restore_db.sh | ||
| rocksdb_dump_test.sh | ||
| run_blob_bench.sh | ||
| run_flash_bench.sh | ||
| run_leveldb.sh | ||
| sample-dump.dmp | ||
| simulated_hybrid_file_system.cc | ||
| simulated_hybrid_file_system.h | ||
| sst_dump.cc | ||
| sst_dump_test.cc | ||
| sst_dump_tool.cc | ||
| trace_analyzer.cc | ||
| trace_analyzer_test.cc | ||
| trace_analyzer_tool.cc | ||
| trace_analyzer_tool.h | ||
| verify_random_db.sh | ||
| write_external_sst.sh | ||
| write_stress.cc | ||
| write_stress_runner.py | ||