183 Commits (b418ace3528460e668d089bb2c300c3f070c2648)

Author	SHA1	Message	Date
Akanksha Mahajan	03fc43976d	Async optimization in scan path (#10602) ... Summary: Optimizations 1. In FilePrefetchBuffer, when data is overlapping between two buffers, it copies the data from first to third buffer, then from second to third buffer to return continuous buffer. This optimization will call ReadAsync on first buffer as soon as buffer is empty instead of getting blocked by second buffer to copy the data. 2. For fixed size readahead_size, FilePrefetchBuffer will issues two async read calls. One with length + readahead_size_/2 on first buffer(if buffer is empty) and readahead_size_/2 on second buffer during seek. - Add readahead_size to db_stress for stress testing these changes in https://github.com/facebook/rocksdb/pull/10632 Pull Request resolved: https://github.com/facebook/rocksdb/pull/10602 Test Plan: - CircleCI tests - stress_test completed successfully export CRASH_TEST_EXT_ARGS="--async_io=1" make crash_test -j32 - db_bench showed no regression With this PR: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=false -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=1 Set seed to 1661876074584472 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags Integrated BlobDB: blob cache disabled RocksDB: version 7.7.0 Date: Tue Aug 30 09:14:34 2022 CPU: 32 * Intel Xeon Processor (Skylake) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 50000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 25939.9 MB (estimated) FileSize: 13732.9 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main1] seekrandom : 270878.018 micros/op 3 ops/sec 30.068 seconds 111 operations; 618.7 MB/s (111 of 111 found) ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=true -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=1 Set seed to 1661875332862922 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags Integrated BlobDB: blob cache disabled RocksDB: version 7.7.0 Date: Tue Aug 30 09:02:12 2022 CPU: 32 * Intel Xeon Processor (Skylake) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 50000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 25939.9 MB (estimated) FileSize: 13732.9 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 WARNING: Assertions are enabled; benchmarks unnecessarily slow ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main1] seekrandom : 358352.488 micros/op 2 ops/sec 30.102 seconds 84 operations; 474.4 MB/s (84 of 84 found) ``` Without PR in main: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=false -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=1 Set seed to 1661876425983045 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags Integrated BlobDB: blob cache disabled RocksDB: version 7.7.0 Date: Tue Aug 30 09:20:26 2022 CPU: 32 * Intel Xeon Processor (Skylake) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 50000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 25939.9 MB (estimated) FileSize: 13732.9 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main1] seekrandom : 280881.953 micros/op 3 ops/sec 30.054 seconds 107 operations; 605.2 MB/s (107 of 107 found) ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=false -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=0 Set seed to 1661876475267771 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags Integrated BlobDB: blob cache disabled RocksDB: version 7.7.0 Date: Tue Aug 30 09:21:15 2022 CPU: 32 * Intel Xeon Processor (Skylake) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 50000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 25939.9 MB (estimated) FileSize: 13732.9 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main1] seekrandom : 363155.084 micros/op 2 ops/sec 30.142 seconds 83 operations; 468.1 MB/s (83 of 83 found) ``` Reviewed By: anand1976 Differential Revision: D39141328 Pulled By: akankshamahajan15 fbshipit-source-id: 560655922c1a437a8569c228abb31b8c0b413120	2 years ago
Akanksha Mahajan	4cd16d65ae	Add new option num_file_reads_for_auto_readahead in BlockBasedTableOptions (#10556) ... Summary: RocksDB does auto-readahead for iterators on noticing more than two reads for a table file if user doesn't provide readahead_size and reads are sequential. A new option num_file_reads_for_auto_readahead is added which can be configured and indicates after how many sequential reads prefetching should be start. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10556 Test Plan: Existing and new unit test Reviewed By: anand1976 Differential Revision: D38947147 Pulled By: akankshamahajan15 fbshipit-source-id: c9eeab495f84a8df7f701c42f04894e46440ad97	2 years ago
anand76	5fbcc8c54d	Update MULTIGET_IO_BATCH_SIZE for non-async MultiGet (#10622) ... Summary: This stat was only getting updated in the async (coroutine) version of MultiGet. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10622 Reviewed By: akankshamahajan15 Differential Revision: D39188790 Pulled By: anand1976 fbshipit-source-id: 7e231507f65fc94c8a006c38f79dfba182a2c24a	2 years ago
Hui Xiao	e484b81eee	Sync dir containing CURRENT after RenameFile on CURRENT as much as possible (#10573) ... Summary: **Context:** Below crash test revealed a bug that directory containing CURRENT file (short for `dir_contains_current_file` below) was not always get synced after a new CURRENT is created and being called with `RenameFile` as part of the creation. This bug exposes a risk that such un-synced directory containing the updated CURRENT can’t survive a host crash (e.g, power loss) hence get corrupted. This then will be followed by a recovery from a corrupted CURRENT that we don't want. The root-cause is that a nullptr `FSDirectory* dir_contains_current_file` sometimes gets passed-down to `SetCurrentFile()` hence in those case `dir_contains_current_file->FSDirectory::FsyncWithDirOptions()` will be skipped (which otherwise will internally call`Env/FS::SyncDic()` ) ``` ./db_stress --acquire_snapshot_one_in=10000 --adaptive_readahead=1 --allow_data_in_errors=True --avoid_unnecessary_blocking_io=0 --backup_max_size=104857600 --backup_one_in=100000 --batch_protection_bytes_per_key=8 --block_size=16384 --bloom_bits=134.8015470676662 --bottommost_compression_type=disable --cache_size=8388608 --checkpoint_one_in=1000000 --checksum_type=kCRC32c --clear_column_family_one_in=0 --compact_files_one_in=1000000 --compact_range_one_in=1000000 --compaction_pri=2 --compaction_ttl=100 --compression_max_dict_buffer_bytes=511 --compression_max_dict_bytes=16384 --compression_type=zstd --compression_use_zstd_dict_trainer=1 --compression_zstd_max_train_bytes=65536 --continuous_verification_interval=0 --data_block_index_type=0 --db=$db --db_write_buffer_size=1048576 --delpercent=5 --delrangepercent=0 --destroy_db_initially=0 --disable_wal=0 --enable_compaction_filter=0 --enable_pipelined_write=1 --expected_values_dir=$exp --fail_if_options_file_error=1 --file_checksum_impl=none --flush_one_in=1000000 --get_current_wal_file_one_in=0 --get_live_files_one_in=1000000 --get_property_one_in=1000000 --get_sorted_wal_files_one_in=0 --index_block_restart_interval=4 --ingest_external_file_one_in=0 --iterpercent=10 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=True --mark_for_compaction_one_file_in=10 --max_background_compactions=20 --max_bytes_for_level_base=10485760 --max_key=10000 --max_key_len=3 --max_manifest_file_size=16384 --max_write_batch_group_size_bytes=64 --max_write_buffer_number=3 --max_write_buffer_size_to_maintain=0 --memtable_prefix_bloom_size_ratio=0.001 --memtable_protection_bytes_per_key=1 --memtable_whole_key_filtering=1 --mmap_read=1 --nooverwritepercent=1 --open_metadata_write_fault_one_in=0 --open_read_fault_one_in=0 --open_write_fault_one_in=0 --ops_per_thread=100000000 --optimize_filters_for_memory=1 --paranoid_file_checks=1 --partition_pinning=2 --pause_background_one_in=1000000 --periodic_compaction_seconds=0 --prefix_size=5 --prefixpercent=5 --prepopulate_block_cache=1 --progress_reports=0 --read_fault_one_in=1000 --readpercent=45 --recycle_log_file_num=0 --reopen=0 --ribbon_starting_level=999 --secondary_cache_fault_one_in=32 --secondary_cache_uri=compressed_secondary_cache://capacity=8388608 --set_options_one_in=10000 --snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=0 --sst_file_manager_bytes_per_truncate=0 --subcompactions=3 --sync_fault_injection=1 --target_file_size_base=2097 --target_file_size_multiplier=2 --test_batches_snapshots=1 --top_level_index_pinning=1 --use_full_merge_v1=1 --use_merge=1 --value_size_mult=32 --verify_checksum=1 --verify_checksum_one_in=1000000 --verify_db_one_in=100000 --verify_sst_unique_id_in_manifest=1 --wal_bytes_per_sync=524288 --write_buffer_size=4194 --writepercent=35 ``` ``` stderr: WARNING: prefix_size is non-zero but memtablerep != prefix_hash db_stress: utilities/fault_injection_fs.cc:748: virtual rocksdb::IOStatus rocksdb::FaultInjectionTestFS::RenameFile(const std::string &, const std::string &, const rocksdb::IOOptions &, rocksdb::IODebugContext *): Assertion `tlist.find(tdn.second) == tlist.end()' failed.` ``` **Summary:** The PR ensured the non-test path pass down a non-null dir containing CURRENT (which is by current RocksDB assumption just db_dir) by doing the following: - Renamed `directory_to_fsync` as `dir_contains_current_file` in `SetCurrentFile()` to tighten the association between this directory and CURRENT file - Changed `SetCurrentFile()` API to require `dir_contains_current_file` being passed-in, instead of making it by default nullptr. - Because `SetCurrentFile()`'s `dir_contains_current_file` is passed down from `VersionSet::LogAndApply()` then `VersionSet::ProcessManifestWrites()` (i.e, think about this as a chain of 3 functions related to MANIFEST update), these 2 functions also got refactored to require `dir_contains_current_file` - Updated the non-test-path callers of these 3 functions to obtain and pass in non-nullptr `dir_contains_current_file`, which by current assumption of RocksDB, is the `FSDirectory* db_dir`. - `db_impl` path will obtain `DBImpl::directories_.getDbDir()` while others with no access to such `directories_` are obtained on the fly by creating such object `FileSystem::NewDirectory(..)` and manage it by unique pointers to ensure short life time. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10573 Test Plan: - `make check` - Passed the repro db_stress command - For future improvement, since we currently don't assert dir containing CURRENT to be non-nullptr due to https://github.com/facebook/rocksdb/pull/10573#pullrequestreview-1087698899, there is still chances that future developers mistakenly pass down nullptr dir containing CURRENT thus resulting skipped sync dir and cause the bug again. Therefore a smarter test (e.g, such as quoted from ajkr "(make) unsynced data loss to be dropping files corresponding to unsynced directory entries") is still needed. Reviewed By: ajkr Differential Revision: D39005886 Pulled By: hx235 fbshipit-source-id: 336fb9090d0cfa6ca3dd580db86268007dde7f5a	2 years ago
anand76	72a3fb3424	Update statistics for async scan readaheads (#10585) ... Summary: Imported a fix to "rocksdb.prefetched.bytes.discarded" stat from https://github.com/facebook/rocksdb/issues/10561, and added a new stat "rocksdb.async.prefetch.abort.micros" to measure time spent waiting for async reads to abort. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10585 Reviewed By: akankshamahajan15 Differential Revision: D39067000 Pulled By: anand1976 fbshipit-source-id: d7cda71abb48017239bd5fd832345a16c7024faf	2 years ago
sdong	4915f89513	WritableFileWriter to allow operation after failure when SyncWithoutFlush() is involved (#10555) ... Summary: https://github.com/facebook/rocksdb/pull/10489 adds an assertion in most functions in WritableFileWriter to check no previous error. However, it only works without calling SyncWithoutFlush(). The nature of SyncWithoutFlush() makes two concurrent call fails to check status code of each other and causing assertion failure. Fix the problem by skipping the check after SyncWithoutFlush() is called and not check status code in SyncWithoutFlush(). Since the original change was not officially released yet, the fix isn't added to HISTORY.md. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10555 Test Plan: Make sure existing tests still pass Reviewed By: anand1976 Differential Revision: D38946208 fbshipit-source-id: 63566732d3f25c8a8342840499cf7b7d745f27c2	2 years ago
sdong	911c0208b9	WritableFileWriter tries to skip operations after failure (#10489) ... Summary: A flag in WritableFileWriter is introduced to remember error has happened. Subsequent operations will fail with an assertion. Those operations, except Close() are not supposed to be called anyway. This change will help catch bug in tests and stress tests and limit damage of a potential bug of continue writing to a file after a failure. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10489 Test Plan: Fix existing unit tests and watch crash tests for a while. Reviewed By: anand1976 Differential Revision: D38473277 fbshipit-source-id: 09aafb971e56cfd7f9ef92ad15b883f54acf1366	2 years ago
Akanksha Mahajan	2acbf386a3	Provide support for direct_reads with async_io (#10197) ... Summary: Provide support for use_direct_reads with async_io. TestPlan: - Updated unit tests - db_bench: Results in https://github.com/facebook/rocksdb/pull/10197#issuecomment-1159239420 - db_stress ``` export CRASH_TEST_EXT_ARGS=" --async_io=1 --use_direct_reads=1" make crash_test -j ``` - Ran db_bench on previous RocksDB version before any async_io implementation (as there have many changes in different PRs in this area) https://github.com/facebook/rocksdb/pull/10197#issuecomment-1160781563. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10197 Reviewed By: anand1976 Differential Revision: D37255646 Pulled By: akankshamahajan15 fbshipit-source-id: fec61ae15bf4d625f79dea56e4f86e0e307ba920	3 years ago
Bo Wang	c073ed7601	Fix typo in comments and code (#10233) ... Summary: Fix typo in comments and code. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10233 Test Plan: Existing unit tests should pass. Reviewed By: jay-zhuang, anand1976 Differential Revision: D37356702 Pulled By: gitbw95 fbshipit-source-id: 32c019adcc6dcc95a9882b38147a310091368e51	3 years ago
Andrew Kryczka	d5d8920f2c	Fix race condition with WAL tracking and `FlushWAL(true /* sync */)` (#10185) ... Summary: `FlushWAL(true /* sync */)` is used internally and for manual WAL sync. It had a bug when used together with `track_and_verify_wals_in_manifest` where the synced size tracked in MANIFEST was larger than the number of bytes actually synced. The bug could be repro'd almost immediately with the following crash test command: `python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=524288 --max_bytes_for_level_base=2097152 --target_file_size_base=524288 --duration=3600 --interval=10 --sync_fault_injection=1 --disable_wal=0 --checkpoint_one_in=1000 --max_key=10000 --value_size_mult=33`. An example error message produced by the above command is shown below. The error sometimes arose from the checkpoint and other times arose from the main stress test DB. ``` Corruption: Size mismatch: WAL (log number: 119) in MANIFEST is 27938 bytes , but actually is 27859 bytes on disk. ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/10185 Test Plan: - repro unit test - the above crash test command no longer finds the error. It does find a different error after a while longer such as "Corruption: WAL file 481 required by manifest but not in directory list" Reviewed By: riversand963 Differential Revision: D37200993 Pulled By: ajkr fbshipit-source-id: 98e0071c1a89f4d009888512ed89f9219779ae5f	3 years ago
Hui Xiao	a5d773e077	Add rate-limiting support to batched MultiGet() (#10159) ... Summary: **Context/Summary:** https://github.com/facebook/rocksdb/pull/9424 added rate-limiting support for user reads, which does not include batched `MultiGet()`s that call `RandomAccessFileReader::MultiRead()`. The reason is that it's harder (compared with RandomAccessFileReader::Read()) to implement the ideal rate-limiting where we first call `RateLimiter::RequestToken()` for allowed bytes to multi-read and then consume those bytes by satisfying as many requests in `MultiRead()` as possible. For example, it can be tricky to decide whether we want partially fulfilled requests within one `MultiRead()` or not. However, due to a recent urgent user request, we decide to pursue an elementary (but a conditionally ineffective) solution where we accumulate enough rate limiter requests toward the total bytes needed by one `MultiRead()` before doing that `MultiRead()`. This is not ideal when the total bytes are huge as we will actually consume a huge bandwidth from rate-limiter causing a burst on disk. This is not what we ultimately want with rate limiter. Therefore a follow-up work is noted through TODO comments. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10159 Test Plan: - Modified existing unit test `DBRateLimiterOnReadTest/DBRateLimiterOnReadTest.NewMultiGet` - Traced the underlying system calls `io_uring_enter` and verified they are 10 seconds apart from each other correctly under the setting of `strace -ftt -e trace=io_uring_enter ./db_bench -benchmarks=multireadrandom -db=/dev/shm/testdb2 -readonly -num=50 -threads=1 -multiread_batched=1 -batch_size=100 -duration=10 -rate_limiter_bytes_per_sec=200 -rate_limiter_refill_period_us=1000000 -rate_limit_bg_reads=1 -disable_auto_compactions=1 -rate_limit_user_ops=1` where each `MultiRead()` read about 2000 bytes (inspected by debugger) and the rate limiter grants 200 bytes per seconds. - Stress test: - Verified `./db_stress (-test_cf_consistency=1/test_batches_snapshots=1) -use_multiget=1 -cache_size=1048576 -rate_limiter_bytes_per_sec=10241024 -rate_limit_bg_reads=1 -rate_limit_user_ops=1` work Reviewed By: ajkr, anand1976 Differential Revision: D37135172 Pulled By: hx235 fbshipit-source-id: 73b8e8f14761e5d4b77235dfe5d41f4eea968bcd	3 years ago
Akanksha Mahajan	8353ae8b27	Add few optimizations in async_io for short scans (#10140) ... Summary: This PR adds few optimizations for async_io for shorter scans. 1. If async_io is enabled, seek would create FilePrefetchBuffer object to fetch the data asynchronously. However `FilePrefetchbuffer::num_file_reads_` wasn't taken into consideration if it calls Next after Seek and would go for Prefetching. This PR fixes that and Next will go for prefetching only if `FilePrefetchbuffer::num_file_reads_` is greater than 2 along with if blocks are sequential. This scenario is only for implicit auto readahead. 2. For seek, when it calls TryReadFromCacheAsync to poll it makes async call as well because TryReadFromCacheAsync flow wasn't changed. So I updated to return after poll instead of further prefetching any data. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10140 Test Plan: 1. Added a unit test 2. Ran crash_test with async_io = 1 to make sure nothing crashes. Reviewed By: anand1976 Differential Revision: D37042242 Pulled By: akankshamahajan15 fbshipit-source-id: b8e6b7cb2ee0886f37a8f53951948b9084e8ffda	3 years ago
zczhu	b6de139df5	Handle "NotSupported" status by default implementation of Close() in … (#10127) ... Summary: The default implementation of Close() function in Directory/FSDirectory classes returns `NotSupported` status. However, we don't want operations that worked in older versions to begin failing after upgrading when run on FileSystems that have not implemented Directory::Close() yet. So we require the upper level that calls Close() function should properly handle "NotSupported" status instead of treating it as an error status. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10127 Reviewed By: ajkr Differential Revision: D36971112 Pulled By: littlepig2013 fbshipit-source-id: 100f0e6ad1191e1acc1ba6458c566a11724cf466	3 years ago
Yanqin Jin	d739de63e5	Fix a bug in WAL tracking (#10087) ... Summary: Closing https://github.com/facebook/rocksdb/issues/10080 When `SyncWAL()` calls `MarkLogsSynced()`, even if there is only one active WAL file, this event should still be added to the MANIFEST. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10087 Test Plan: make check Reviewed By: ajkr Differential Revision: D36797580 Pulled By: riversand963 fbshipit-source-id: 24184c9dd606b3939a454ed41de6e868d1519999	3 years ago
Zichen Zhu	65893ad959	Explicitly closing all directory file descriptors (#10049) ... Summary: Currently, the DB directory file descriptor is left open until the deconstruction process (`DB::Close()` does not close the file descriptor). To verify this, comment out the lines between `db_ = nullptr` and `db_->Close()` (line 512, 513, 514, 515 in ldb_cmd.cc) to leak the ``db_'' object, build `ldb` tool and run ``` strace --trace=open,openat,close ./ldb --db=$TEST_TMPDIR --ignore_unknown_options put K1 V1 --create_if_missing ``` There is one directory file descriptor that is not closed in the strace log. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10049 Test Plan: Add a new unit test DBBasicTest.DBCloseAllDirectoryFDs: Open a database with different WAL directory and three different data directories, and all directory file descriptors should be closed after calling Close(). Explicitly call Close() after a directory file descriptor is not used so that the counter of directory open and close should be equivalent. Reviewed By: ajkr, hx235 Differential Revision: D36722135 Pulled By: littlepig2013 fbshipit-source-id: 07bdc2abc417c6b30997b9bbef1f79aa757b21ff	3 years ago
Akanksha Mahajan	28ea1fb44a	Provide support for IOTracing for ReadAsync API (#9833) ... Summary: Same as title Pull Request resolved: https://github.com/facebook/rocksdb/pull/9833 Test Plan: Add unit test and manually check the output of tracing logs For fixed readahead_size it logs as: ``` Access Time : 193352113447923 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 15075 , IO Status: OK, Length: 12288, Offset: 659456 Access Time : 193352113465232 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 14425 , IO Status: OK, Length: 12288, Offset: 671744 Access Time : 193352113481539 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 13062 , IO Status: OK, Length: 12288, Offset: 684032 Access Time : 193352113497692 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 13649 , IO Status: OK, Length: 12288, Offset: 696320 Access Time : 193352113520043 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 19384 , IO Status: OK, Length: 12288, Offset: 708608 Access Time : 193352113538401 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 15406 , IO Status: OK, Length: 12288, Offset: 720896 Access Time : 193352113554855 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 13670 , IO Status: OK, Length: 12288, Offset: 733184 Access Time : 193352113571624 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 13855 , IO Status: OK, Length: 12288, Offset: 745472 Access Time : 193352113587924 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 13953 , IO Status: OK, Length: 12288, Offset: 757760 Access Time : 193352113603285 , File Name: 000026.sst , File Operation: Prefetch , Latency: 59 , IO Status: Not implemented: Prefetch not supported, Length: 8868, Offset: 898349 ``` For implicit readahead: ``` Access Time : 193351865156587 , File Name: 000026.sst , File Operation: Prefetch , Latency: 48 , IO Status: Not implemented: Prefetch not supported, Length: 12266, Offset: 391174 Access Time : 193351865160354 , File Name: 000026.sst , File Operation: Prefetch , Latency: 51 , IO Status: Not implemented: Prefetch not supported, Length: 12266, Offset: 395248 Access Time : 193351865164253 , File Name: 000026.sst , File Operation: Prefetch , Latency: 49 , IO Status: Not implemented: Prefetch not supported, Length: 12266, Offset: 399322 Access Time : 193351865165461 , File Name: 000026.sst , File Operation: ReadAsync , Latency: 222871 , IO Status: OK, Length: 135168, Offset: 401408 ``` Reviewed By: anand1976 Differential Revision: D35601634 Pulled By: akankshamahajan15 fbshipit-source-id: 5a4f32a850af878efa0767bd5706380152a1f26e	3 years ago
Changyu Bi	8515bd50c9	Support read rate-limiting in SequentialFileReader (#9973) ... Summary: Added rate limiter and read rate-limiting support to SequentialFileReader. I've updated call sites to SequentialFileReader::Read with appropriate IO priority (or left a TODO and specified IO_TOTAL for now). The PR is separated into four commits: the first one added the rate-limiting support, but with some fixes in the unit test since the number of request bytes from rate limiter in SequentialFileReader are not accurate (there is overcharge at EOF). The second commit fixed this by allowing SequentialFileReader to check file size and determine how many bytes are left in the file to read. The third commit added benchmark related code. The fourth commit moved the logic of using file size to avoid overcharging the rate limiter into backup engine (the main user of SequentialFileReader). Pull Request resolved: https://github.com/facebook/rocksdb/pull/9973 Test Plan: - `make check`, backup_engine_test covers usage of SequentialFileReader with rate limiter. - Run db_bench to check if rate limiting is throttling as expected: Verified that reads and writes are together throttled at 2MB/s, and at 0.2MB chunks that are 100ms apart. - Set up: `./db_bench --benchmarks=fillrandom -db=/dev/shm/test_rocksdb` - Benchmark: ``` strace -ttfe read,write ./db_bench --benchmarks=backup -db=/dev/shm/test_rocksdb --backup_rate_limit=2097152 --use_existing_db strace -ttfe read,write ./db_bench --benchmarks=restore -db=/dev/shm/test_rocksdb --restore_rate_limit=2097152 --use_existing_db ``` - db bench on backup and restore to ensure no performance regression. - backup (avg over 50 runs): pre-change: 1.90443e+06 micros/op; post-change: 1.8993e+06 micros/op (improve by 0.2%) - restore (avg over 50 runs): pre-change: 1.79105e+06 micros/op; post-change: 1.78192e+06 micros/op (improve by 0.5%) ``` # Set up ./db_bench --benchmarks=fillrandom -db=/tmp/test_rocksdb -num=10000000 # benchmark TEST_TMPDIR=/tmp/test_rocksdb NUM_RUN=50 for ((j=0;j<$NUM_RUN;j++)) do ./db_bench -db=$TEST_TMPDIR -num=10000000 -benchmarks=backup -use_existing_db | egrep 'backup' # Restore #./db_bench -db=$TEST_TMPDIR -num=10000000 -benchmarks=restore -use_existing_db done > rate_limit.txt && awk -v NUM_RUN=$NUM_RUN '{sum+=$3;sum_sqrt+=$3^2}END{print sum/NUM_RUN, sqrt(sum_sqrt/NUM_RUN-(sum/NUM_RUN)^2)}' rate_limit.txt >> rate_limit_2.txt ``` Reviewed By: hx235 Differential Revision: D36327418 Pulled By: cbi42 fbshipit-source-id: e75d4307cff815945482df5ba630c1e88d064691	3 years ago
Akanksha Mahajan	a479c2c2b2	Fix stress test failure "Corruption: checksum mismatch" or "Iterator Diverged" with async_io enabled (#10032) ... Summary: In case of non sequential reads with `async_io`, `FilePRefetchBuffer::TryReadFromCacheAsync` can be called for previous blocks with `offset < bufs_[curr_].offset_` which wasn't handled correctly resulting wrong data being returned from buffer. Since `FilePRefetchBuffer::PrefetchAsync` can be called for any data block, it sets `prev_len_` to 0 indicating `FilePRefetchBuffer::TryReadFromCacheAsync` to go for the prefetching even though offset < bufs_[curr_].offset_ This is because async prefetching is always done in second buffer (to avoid mutex) even though curr_ is empty leading to offset < bufs_[curr_].offset_ in some cases. If prev_len_ is non zero then `TryReadFromCacheAsync` returns false if `offset < bufs_[curr_].offset_ && prev_len != 0` indicating reads are not sequential and previous call wasn't PrefetchAsync. - This PR also simplifies `FilePRefetchBuffer::TryReadFromCacheAsync` as it was getting complicated covering different scenarios based on `async_io` enabled/disabled. If `for_compaction` is set true, it now calls `FilePRefetchBufferTryReadFromCache` following synchronous flow as before. Its decided in BlockFetcher.cc Pull Request resolved: https://github.com/facebook/rocksdb/pull/10032 Test Plan: 1. export CRASH_TEST_EXT_ARGS=" --async_io=1" make crash_test -j completed successfully locally 2. make crash_test -j completed successfully locally 3. Reran CircleCi mini crashtest job 4 - 5 times. 4. Updated prefetch_test for more coverage. Reviewed By: anand1976 Differential Revision: D36579858 Pulled By: akankshamahajan15 fbshipit-source-id: 0c428d62b45e12e082a83acf533a5e37a584bedf	3 years ago
Akanksha Mahajan	2db6a4a1d6	Seek parallelization (#9994) ... Summary: The RocksDB iterator is a hierarchy of iterators. MergingIterator maintains a heap of LevelIterators, one for each L0 file and for each non-zero level. The Seek() operation naturally lends itself to parallelization, as it involves positioning every LevelIterator on the correct data block in the correct SST file. It lookups a level for a target key, to find the first key that's >= the target key. This typically involves reading one data block that is likely to contain the target key, and scan forward to find the first valid key. The forward scan may read more data blocks. In order to find the right data block, the iterator may read some metadata blocks (required for opening a file and searching the index). This flow can be parallelized. Design: Seek will be called two times under async_io option. First seek will send asynchronous request to prefetch the data blocks at each level and second seek will follow the normal flow and in FilePrefetchBuffer::TryReadFromCacheAsync it will wait for the Poll() to get the results and add the iterator to min_heap. - Status::TryAgain is passed down from FilePrefetchBuffer::PrefetchAsync to block_iter_.Status indicating asynchronous request has been submitted. - If for some reason asynchronous request returns error in submitting the request, it will fallback to sequential reading of blocks in one pass. - If the data already exists in prefetch_buffer, it will return the data without prefetching further and it will be treated as single pass of seek. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9994 Test Plan: - **Run Regressions.** ``` ./db_bench -db=/tmp/prefix_scan_prefetch_main -benchmarks="fillseq" -key_size=32 -value_size=512 -num=5000000 -use_direct_io_for_flush_and_compaction=true -target_file_size_base=16777216 ``` i) Previous release 7.0 run for normal prefetching with async_io disabled: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.0 Date: Thu Mar 17 13:11:34 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 483618.390 micros/op 2 ops/sec; 338.9 MB/s (249 of 249 found) ``` ii) normal prefetching after changes with async_io disable: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Set seed to 1652922591315307 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.3 Date: Wed May 18 18:09:51 2022 CPU: 32 * Intel Xeon Processor (Skylake) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 483080.466 micros/op 2 ops/sec 120.287 seconds 249 operations; 340.8 MB/s (249 of 249 found) ``` iii) db_bench with async_io enabled completed succesfully ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 -async_io=1 -adaptive_readahead=1 Set seed to 1652924062021732 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.3 Date: Wed May 18 18:34:22 2022 CPU: 32 * Intel Xeon Processor (Skylake) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 553913.576 micros/op 1 ops/sec 120.199 seconds 217 operations; 293.6 MB/s (217 of 217 found) ``` - db_stress with async_io disabled completed succesfully ``` export CRASH_TEST_EXT_ARGS=" --async_io=0" make crash_test -j ``` I**n Progress**: db_stress with async_io is failing and working on debugging/fixing it. Reviewed By: anand1976 Differential Revision: D36459323 Pulled By: akankshamahajan15 fbshipit-source-id: abb1cd944abe712bae3986ae5b16704b3338917c	3 years ago
Bo Wang	5be1579ead	Address comments for PR #9988 and #9996 (#10020) ... Summary: 1. The latest change of DecideRateLimiterPriority in https://github.com/facebook/rocksdb/pull/9988 is reverted. 2. For https://github.com/facebook/rocksdb/blob/main/db/builder.cc#L345-L349 2.1. Remove `we will regrad this verification as user reads` from the comments. 2.2. `Do not set` the read_options.rate_limiter_priority to Env::IO_USER . Flush should be a background job. 2.3. Update db_rate_limiter_test.cc. 3. In IOOptions, mark `prio` as deprecated for future removal. 4. In `file_system.h`, mark `IOPriority` as deprecated for future removal. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10020 Test Plan: Unit tests. Reviewed By: ajkr Differential Revision: D36525317 Pulled By: gitbw95 fbshipit-source-id: 011ba421822f8a124e6d25a2661c4e242df6ad36	3 years ago
gitbw95	4da34b97ee	Set Read rate limiter priority dynamically and pass it to FS (#9996) ... Summary: ### Context: Background compactions and flush generate large reads and writes, and can be long running, especially for universal compaction. In some cases, this can impact foreground reads and writes by users. ### Solution User, Flush, and Compaction reads share some code path. For this task, we update the rate_limiter_priority in ReadOptions for code paths (e.g. FindTable (mainly in BlockBasedTable::Open()) and various iterators), and eventually update the rate_limiter_priority in IOOptions for FSRandomAccessFile. **This PR is for the Read path.** The **Read:** dynamic priority for different state are listed as follows: | State | Normal | Delayed | Stalled | | ----- | ------ | ------- | ------- | | Flush (verification read in BuildTable()) | IO_USER | IO_USER | IO_USER | | Compaction | IO_LOW | IO_USER | IO_USER | | User | User provided | User provided | User provided | We will respect the read_options that the user provided and will not set it. The only sst read for Flush is the verification read in BuildTable(). It claims to be "regard as user read". **Details** 1. Set read_options.rate_limiter_priority dynamically: - User: Do not update the read_options. Use the read_options that the user provided. - Compaction: Update read_options in CompactionJob::ProcessKeyValueCompaction(). - Flush: Update read_options in BuildTable(). 2. Pass the rate limiter priority to FSRandomAccessFile functions: - After calling the FindTable(), read_options is passed through GetTableReader(table_cache.cc), BlockBasedTableFactory::NewTableReader(block_based_table_factory.cc), and BlockBasedTable::Open(). The Open() needs some updates for the ReadOptions variable and the updates are also needed for the called functions, including PrefetchTail(), PrepareIOOptions(), ReadFooterFromFile(), ReadMetaIndexblock(), ReadPropertiesBlock(), PrefetchIndexAndFilterBlocks(), and ReadRangeDelBlock(). - In RandomAccessFileReader, the functions to be updated include Read(), MultiRead(), ReadAsync(), and Prefetch(). - Update the downstream functions of NewIndexIterator(), NewDataBlockIterator(), and BlockBasedTableIterator(). ### Test Plans Add unit tests. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9996 Reviewed By: anand1976 Differential Revision: D36452483 Pulled By: gitbw95 fbshipit-source-id: 60978204a4f849bb9261cb78d9bc1cb56d6008cf	3 years ago
gitbw95	05c678e135	Set Write rate limiter priority dynamically and pass it to FS (#9988) ... Summary: ### Context: Background compactions and flush generate large reads and writes, and can be long running, especially for universal compaction. In some cases, this can impact foreground reads and writes by users. From the RocksDB perspective, there can be two kinds of rate limiters, the internal (native) one and the external one. - The internal (native) rate limiter is introduced in [the wiki](https://github.com/facebook/rocksdb/wiki/Rate-Limiter). Currently, only IO_LOW and IO_HIGH are used and they are set statically. - For the external rate limiter, in FSWritableFile functions, IOOptions is open for end users to set and get rate_limiter_priority for their own rate limiter. Currently, RocksDB doesn’t pass the rate_limiter_priority through IOOptions to the file system. ### Solution During the User Read, Flush write, Compaction read/write, the WriteController is used to determine whether DB writes are stalled or slowed down. The rate limiter priority (Env::IOPriority) can be determined accordingly. We decided to always pass the priority in IOOptions. What the file system does with it should be a contract between the user and the file system. We would like to set the rate limiter priority at file level, since the Flush/Compaction job level may be too coarse with multiple files and block IO level is too granular. **This PR is for the Write path.** The **Write:** dynamic priority for different state are listed as follows: | State | Normal | Delayed | Stalled | | ----- | ------ | ------- | ------- | | Flush | IO_HIGH | IO_USER | IO_USER | | Compaction | IO_LOW | IO_USER | IO_USER | Flush and Compaction writes share the same call path through BlockBaseTableWriter, WritableFileWriter, and FSWritableFile. When a new FSWritableFile object is created, its io_priority_ can be set dynamically based on the state of the WriteController. In WritableFileWriter, before the call sites of FSWritableFile functions, WritableFileWriter::DecideRateLimiterPriority() determines the rate_limiter_priority. The options (IOOptions) argument of FSWritableFile functions will be updated with the rate_limiter_priority. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9988 Test Plan: Add unit tests. Reviewed By: anand1976 Differential Revision: D36395159 Pulled By: gitbw95 fbshipit-source-id: a7c82fc29759139a1a07ec46c37dbf7e753474cf	3 years ago
Hui Xiao	f6339de0d2	Clarify some SequentialFileReader::Read logic (#10002) ... Summary: **Context/Summary:** The logic related to PositionedRead in SequentialFileReader::Read confused me a bit as discussed here https://github.com/facebook/rocksdb/pull/9973#discussion_r872869256. Therefore I added a drawing with help from cbi42. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10002 Test Plan: - no code change Reviewed By: anand1976, cbi42 Differential Revision: D36422632 Pulled By: hx235 fbshipit-source-id: 9a8311d2365564f90d216c430f542fc11b2d9cde	3 years ago
sdong	736a7b5433	Remove own ToString() (#9955) ... Summary: ToString() is created as some platform doesn't support std::to_string(). However, we've already used std::to_string() by mistake for 16 months (in db/db_info_dumper.cc). This commit just remove ToString(). Pull Request resolved: https://github.com/facebook/rocksdb/pull/9955 Test Plan: Watch CI tests Reviewed By: riversand963 Differential Revision: D36176799 fbshipit-source-id: bdb6dcd0e3a3ab96a1ac810f5d0188f684064471	3 years ago
sdong	49628c9a83	Use std::numeric_limits<> (#9954) ... Summary: Right now we still don't fully use std::numeric_limits but use a macro, mainly for supporting VS 2013. Right now we only support VS 2017 and up so it is not a problem. The code comment claims that MinGW still needs it. We don't have a CI running MinGW so it's hard to validate. since we now require C++17, it's hard to imagine MinGW would still build RocksDB but doesn't support std::numeric_limits<>. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9954 Test Plan: See CI Runs. Reviewed By: riversand963 Differential Revision: D36173954 fbshipit-source-id: a35a73af17cdcae20e258cdef57fcf29a50b49e0	3 years ago
Akanksha Mahajan	fce65e7e4f	Fix bug in async_io path which reads incorrect length (#9916) ... Summary: In FilePrefetchBuffer, in case data is overlapping between two buffers and more data is required to read and copy that to third buffer, incorrect length was updated resulting in ``` Iterator diverged from control iterator which has value 00000000000310C3000000000000012B0000000000000274 total_order_seek: 1 auto_prefix_mode: 0 S 000000000002C37F000000000000012B000000000000001C NNNPPPPPNN; total_order_seek: 1 auto_prefix_mode: 0 S 000000000002F10B00000000000000BF78787878787878 NNNPNNNNPN; total_order_seek: 1 auto_prefix_mode: 0 S 00000000000310C3000000000000012B000000000000026B iterator is not valid Control CF default db_stress: db_stress_tool/db_stress_test_base.cc:1388: void rocksdb::StressTest::VerifyIterator(rocksdb::ThreadState*, rocksdb::ColumnFamilyHandle*, const rocksdb::ReadOptions&, rocksdb::Iterator*, rocksdb::Iterator*, rocksdb::StressTest::LastIterateOp, const rocksdb::Slice&, const string&, bool*): Assertion `false' failed. Aborted (core dumped) ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/9916 Test Plan: ``` - CircleCI jobs - Ran db_stress with OPTIONS file which caught the bug ./db_stress --acquire_snapshot_one_in=10000 --adaptive_readahead=0 --async_io=1 --avoid_flush_during_recovery=0 --avoid_unnecessary_blocking_io=1 --backup_max_size=104857600 --backup_one_in=0 --batch_protection_bytes_per_key=0 --block_size=16384 --bloom_bits=42.26248932628998 --bottommost_compression_type=disable --cache_index_and_filter_blocks=0 --cache_size=8388608 --checkpoint_one_in=0 --checksum_type=kxxHash --clear_column_family_one_in=0 --compact_files_one_in=1000000 --compact_range_one_in=1000000 --compaction_ttl=0 --compression_max_dict_buffer_bytes=1073741823 --compression_max_dict_bytes=16384 --compression_parallel_threads=1 --compression_type=zstd --compression_zstd_max_train_bytes=65536 --continuous_verification_interval=0 --db=/dev/shm/rocksdb/ --db_write_buffer_size=134217728 --delpercent=5 --delrangepercent=0 --destroy_db_initially=0 --detect_filter_construct_corruption=0 --disable_wal=0 --enable_blob_files=0 --enable_compaction_filter=0 --enable_pipelined_write=0 --fail_if_options_file_error=0 --file_checksum_impl=none --flush_one_in=1000000 --format_version=4 --get_current_wal_file_one_in=0 --get_live_files_one_in=1000000 --get_property_one_in=1000000 --get_sorted_wal_files_one_in=0 --index_block_restart_interval=12 --index_type=2 --ingest_external_file_one_in=0 --iterpercent=10 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=True --long_running_snapshots=0 --mark_for_compaction_one_file_in=0 --max_background_compactions=20 --max_bytes_for_level_base=10485760 --max_key=25000000 --max_key_len=3 --max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=1048576 --max_write_buffer_number=3 --max_write_buffer_size_to_maintain=8388608 --memtable_prefix_bloom_size_ratio=0.001 --memtable_whole_key_filtering=1 --memtablerep=skip_list --mmap_read=0 --mock_direct_io=False --nooverwritepercent=1 --open_files=100 --open_metadata_write_fault_one_in=0 --open_read_fault_one_in=0 --open_write_fault_one_in=16 --ops_per_thread=100000000 --optimize_filters_for_memory=0 --paranoid_file_checks=1 --partition_filters=0 --partition_pinning=1 --pause_background_one_in=1000000 --periodic_compaction_seconds=0 --prefix_size=-1 --prefixpercent=0 --prepopulate_block_cache=0 --progress_reports=0 --read_fault_one_in=0 --read_only=0 --readpercent=50 --recycle_log_file_num=1 --reopen=0 --reserve_table_reader_memory=0 --ribbon_starting_level=999 --secondary_cache_fault_one_in=0 --secondary_catch_up_one_in=0 --set_options_one_in=10000 --snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=104857600 --sst_file_manager_bytes_per_truncate=0 --subcompactions=2 --sync=0 --sync_fault_injection=False --target_file_size_base=2097152 --target_file_size_multiplier=2 --test_batches_snapshots=0 --test_cf_consistency=0 --top_level_index_pinning=3 --unpartitioned_pinning=3 --use_blob_db=0 --use_block_based_filter=0 --use_clock_cache=0 --use_direct_io_for_flush_and_compaction=1 --use_direct_reads=0 --use_full_merge_v1=0 --use_merge=0 --use_multiget=0 --use_txn=0 --user_timestamp_size=0 --value_size_mult=32 --verify_checksum=1 --verify_checksum_one_in=1000000 --verify_db_one_in=100000 --wal_compression=zstd --write_buffer_size=4194304 --write_dbid_to_manifest=0 --writepercent=35 --options_file=/home/akankshamahajan/OPTIONS.orig -column_families=1 db_bench with async_io enabled to make sure db_bench completes successfully without any failure. - ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 -async_io=1 ``` crash_test in progress Reviewed By: anand1976 Differential Revision: D35985789 Pulled By: akankshamahajan15 fbshipit-source-id: 5abe185f34caa99ca587d4bdc8954bd0802b1bf9	3 years ago
Akanksha Mahajan	3653029dda	Add stats related to async prefetching (#9845) ... Summary: Add stats PREFETCHED_BYTES_DISCARDED and POLL_WAIT_MICROS. PREFETCHED_BYTES_DISCARDED records number of prefetched bytes discarded by FilePrefetchBuffer. POLL_WAIT_MICROS records the time taken by underling file_system Poll API. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9845 Test Plan: Update existing tests Reviewed By: anand1976 Differential Revision: D35909694 Pulled By: akankshamahajan15 fbshipit-source-id: e009ef940bb9ed72c9446f5529095caabb8a1e36	3 years ago
Akanksha Mahajan	5bd374b392	Add experimental new FS API AbortIO to cancel read request (#9901) ... Summary: Add experimental new API AbortIO in FileSystem to abort the read requests submitted asynchronously through ReadAsync API. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9901 Test Plan: Existing tests Reviewed By: anand1976 Differential Revision: D35885591 Pulled By: akankshamahajan15 fbshipit-source-id: df3944e6e9e6e487af1fa688376b4abb6837fb02	3 years ago
Hui Xiao	e83c55439a	Conditionally declare and define variable that is unused in LITE mode (#9854) ... Summary: Context: As mentioned in https://github.com/facebook/rocksdb/issues/9701, we have the following in LITE=1 make static_lib for v7.0.2 ``` CC file/sequence_file_reader.o CC file/sst_file_manager_impl.o CC file/writable_file_writer.o In file included from file/writable_file_writer.cc:10: ./file/writable_file_writer.h:163:15: error: private field 'temperature_' is not used [-Werror,-Wunused-private-field] Temperature temperature_; ^ 1 error generated. make: *** [file/writable_file_writer.o] Error 1 ``` as titled Pull Request resolved: https://github.com/facebook/rocksdb/pull/9854 Test Plan: - Local `LITE=1 make static_lib` reveals the same error and error is gone after this fix - CI Reviewed By: ajkr, jay-zhuang Differential Revision: D35706585 Pulled By: hx235 fbshipit-source-id: 7743310298231ad6866304ffa2225c8abdc91d9a	3 years ago
Akanksha Mahajan	0c7f455f85	Make initial auto readahead_size configurable (#9836) ... Summary: Make initial auto readahead_size configurable Pull Request resolved: https://github.com/facebook/rocksdb/pull/9836 Test Plan: Added new unit test Ran regression: Without change: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.0 Date: Thu Mar 17 13:11:34 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 483618.390 micros/op 2 ops/sec; 338.9 MB/s (249 of 249 found) ``` With this change: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Set seed to 1649895440554504 because --seed was 0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.2 Date: Wed Apr 13 17:17:20 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] ... finished 100 ops seekrandom : 476892.488 micros/op 2 ops/sec; 344.6 MB/s (252 of 252 found) ``` Reviewed By: anand1976 Differential Revision: D35632815 Pulled By: akankshamahajan15 fbshipit-source-id: c8057a88f9294c9d03b1d434b03affe02f74d796	3 years ago
Akanksha Mahajan	63e68a4e77	Enable async prefetching for ReadOptions.readahead_size (#9827) ... Summary: Currently async prefetching is enabled for implicit internal auto readahead in FilePrefetchBuffer if `ReadOptions.async_io` is set. This PR enables async prefetching for `ReadOptions.readahead_size` when `ReadOptions.async_io` is set true. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9827 Test Plan: Update unit test Reviewed By: anand1976 Differential Revision: D35552129 Pulled By: akankshamahajan15 fbshipit-source-id: d9f9a96672852a591375a21eef15355cf3289f5c	3 years ago
Akanksha Mahajan	f3bcac39a6	Fix stress test failure in ReadAsync. (#9824) ... Summary: Fix stress test failure in ReadAsync by ignoring errors injected during async read by FaultInjectionFS. Failure: ``` WARNING: prefix_size is non-zero but memtablerep != prefix_hash Didn't get expected error from MultiGet. num_keys 14 Expected 1 errors, seen 0 Callstack that injected the fault Injected error type = 32538 Message: error; #0 ./db_stress() [0x6f7dd4] rocksdb::port::SaveStack(int*, int) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/port/stack_trace.cc:152 https://github.com/facebook/rocksdb/issues/1 ./db_stress() [0x7f2bda] rocksdb::FaultInjectionTestFS::InjectThreadSpecificReadError(rocksdb::FaultInjectionTestFS::ErrorOperation, rocksdb::Slice*, bool, char*, bool, bool*) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/utilities/fault_injection_fs.cc:891 https://github.com/facebook/rocksdb/issues/2 ./db_stress() [0x7f2e78] rocksdb::TestFSRandomAccessFile::Read(unsigned long, unsigned long, rocksdb::IOOptions const&, rocksdb::Slice*, char*, rocksdb::IODebugContext*) const /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/utilities/fault_injection_fs.cc:367 https://github.com/facebook/rocksdb/issues/3 ./db_stress() [0x6483d7] rocksdb::(anonymous namespace)::CompositeRandomAccessFileWrapper::Read(unsigned long, unsigned long, rocksdb::Slice*, char*) const /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/env/composite_env.cc:61 https://github.com/facebook/rocksdb/issues/4 ./db_stress() [0x654564] rocksdb::(anonymous namespace)::LegacyRandomAccessFileWrapper::Read(unsigned long, unsigned long, rocksdb::IOOptions const&, rocksdb::Slice*, char*, rocksdb::IODebugContext*) const /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/env/env.cc:152 https://github.com/facebook/rocksdb/issues/5 ./db_stress() [0x659b3b] rocksdb::FSRandomAccessFile::ReadAsync(rocksdb::FSReadRequest&, rocksdb::IOOptions const&, std::function<void (rocksdb::FSReadRequest const&, void*)>, void*, void**, std::function<void (void*)>*, rocksdb::IODebugContext*) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/./include/rocksdb/file_system.h:896 https://github.com/facebook/rocksdb/issues/6 ./db_stress() [0x8b8bab] rocksdb::RandomAccessFileReader::ReadAsync(rocksdb::FSReadRequest&, rocksdb::IOOptions const&, std::function<void (rocksdb::FSReadRequest const&, void*)>, void*, void**, std::function<void (void*)>*, rocksdb::Env::IOPriority) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/file/random_access_file_reader.cc:459 https://github.com/facebook/rocksdb/issues/7 ./db_stress() [0x8b501f] rocksdb::FilePrefetchBuffer::ReadAsync(rocksdb::IOOptions const&, rocksdb::RandomAccessFileReader*, rocksdb::Env::IOPriority, unsigned long, unsigned long, unsigned long, unsigned int) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/file/file_prefetch_buffer.cc:124 https://github.com/facebook/rocksdb/issues/8 ./db_stress() [0x8b55fc] rocksdb::FilePrefetchBuffer::PrefetchAsync(rocksdb::IOOptions const&, rocksdb::RandomAccessFileReader*, unsigned long, unsigned long, unsigned long, rocksdb::Env::IOPriority, bool&) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/file/file_prefetch_buffer.cc:363 https://github.com/facebook/rocksdb/issues/9 ./db_stress() [0x8b61f8] rocksdb::FilePrefetchBuffer::TryReadFromCacheAsync(rocksdb::IOOptions const&, rocksdb::RandomAccessFileReader*, unsigned long, unsigned long, rocksdb::Slice*, rocksdb::Status*, rocksdb::Env::IOPriority, bool) /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/file/file_prefetch_buffer.cc:482 https://github.com/facebook/rocksdb/issues/10 ./db_stress() [0x745e04] rocksdb::BlockFetcher::TryGetFromPrefetchBuffer() /data/sandcastle/boxes/trunk-hg-fbcode-fbsource/fbcode/internal_repo_rocksdb/repo/table/block_fetcher.cc:76 ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/9824 Test Plan: ``` ./db_stress --acquire_snapshot_one_in=10000 --adaptive_readahead=1 --allow_concurrent_memtable_write=0 --async_io=1 --atomic_flush=1 --avoid_flush_during_recovery=0 --avoid_unnecessary_blocking_io=0 -- backup_max_size=104857600 --backup_one_in=100000 --batch_protection_bytes_per_key=0 --block_size=16384 --bloom_bits=5.037629726741734 --bottommost_compression_type=lz4hc --cache_index_and_filter_blocks=0 --cache_size=8388608 --checkpoint_one_in=1000000 --checksum_type=kxxHash --clear_column_family_one_in=0 --column_families=1 --compact_files_one_in=1000000 --compact_range_one_in=1000000 --compaction_ttl=100 --compression_max_dict_buffer_bytes=1073741823 --compression_max_dict_bytes=16384 --compression_parallel_threads=1 --compression_type=zstd --compression_zstd_max_train_bytes=0 --continuous_verification_interval=0 --db=/home/akankshamahajan/dev/shm/rocksdb/rocksdb_crashtest_blackbox --db_write_buffer_size=8388608 --delpercent=0 --delrangepercent=0 --destroy_db_initially=0 - detect_filter_construct_corruption=1 --disable_wal=1 --enable_compaction_filter=0 --enable_pipelined_write=0 --expected_values_dir=/home/akankshamahajan/dev/shm/rocksdb/rocksdb_crashtest_expected --experimental_mempurge_threshold=8.772789063014715 --fail_if_options_file_error=0 --file_checksum_impl=crc32c --flush_one_in=1000000 --format_version=3 --get_current_wal_file_one_in=0 --get_live_files_one_in=1000000 --get_property_one_in=1000000 --get_sorted_wal_files_one_in=0 --index_block_restart_interval=15 --index_type=3 --iterpercent=0 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=False --long_running_snapshots=0 --mark_for_compaction_one_file_in=0 --max_background_compactions=1 --max_bytes_for_level_base=67108864 --max_key=25000000 --max_key_len=3 --max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=16777216 --max_write_buffer_number=3 --max_write_buffer_size_to_maintain=2097152 --memtable_prefix_bloom_size_ratio=0.001 --memtable_whole_key_filtering=1 --memtablerep=skip_list --mmap_read=0 --mock_direct_io=True --nooverwritepercent=1 --open_files=-1 --open_metadata_write_fault_one_in=0 --open_read_fault_one_in=0 --open_write_fault_one_in=0 --ops_per_thread=100000000 --optimize_filters_for_memory=0 --paranoid_file_checks=1 --partition_filters=0 --partition_pinning=2 --pause_background_one_in=1000000 --periodic_compaction_seconds=1000 --prefix_size=-1 --prefixpercent=0 --prepopulate_block_cache=0 --progress_reports=0 --read_fault_one_in=32 --readpercent=100 --recycle_log_file_num=1 --reopen=0 --reserve_table_reader_memory=1 --ribbon_starting_level=999 --secondary_cache_fault_one_in=0 --set_options_one_in=0 --snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=0 --sst_file_manager_bytes_per_truncate=0 --subcompactions=2 --sync=0 --sync_fault_injection=False --target_file_size_base=16777216 --target_file_size_multiplier=1 --test_batches_snapshots=0 --top_level_index_pinning=3 --unpartitioned_pinning=2 --use_block_based_filter=0 --use_clock_cache=0 --use_direct_io_for_flush_and_compaction=1 --use_direct_reads=0 --use_full_merge_v1=0 --use_merge=1 --use_multiget=1 --user_timestamp_size=0 --value_size_mult=32 --verify_checksum=1 --verify_checksum_one_in=1000000 --verify_db_one_in=100000 --wal_compression=none --write_buffer_size=33554432 --write_dbid_to_manifest=1 --write_fault_one_in=0 --writepercent=0 ``` Reviewed By: anand1976 Differential Revision: D35514566 Pulled By: akankshamahajan15 fbshipit-source-id: e2a868fdd7422604774c1419738f9926a21e92a4	3 years ago
Akanksha Mahajan	3fc2eaf561	Fix valgrind test failure for async read (#9819) ... Summary: Since all plaftorms don't support io_uring. So updated the unit test to take that into consideration when testing async reads in unit tests. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9819 Test Plan: valgrind --error-exitcode=2 --leak-check=full ./prefetch_test --gtest_filter=PrefetchTest2.ReadAsyncWithPosixFS CircleCI jobs Reviewed By: pdillinger Differential Revision: D35469959 Pulled By: akankshamahajan15 fbshipit-source-id: b170459ec816487fc0a13b1d55dbbe4f754b2eba	3 years ago
Akanksha Mahajan	7ea26abb8b	Fix reseting of async_read_in_progress_ variable in FilePrefetchBuffer to call Poll API (#9815) ... Summary: Currently RocksDB reset async_read_in_progress_ in callback due to which underlying filesystem relying on Poll API won't be called leading to stale memory access. In order to fix it, async_read_in_progress_ will be reset after Poll API is called to make sure underlying file_system waiting on Poll can clear its state or take appropriate action. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9815 Test Plan: CircleCI tests Reviewed By: anand1976 Differential Revision: D35451534 Pulled By: akankshamahajan15 fbshipit-source-id: b70ef6251a7aa9ed4876ba5e5100baa33d7d474c	3 years ago
Akanksha Mahajan	0b8f885939	Update stats for Read and ReadAsync in random_access_file_reader for async prefetching (#9810) ... Summary: Update stats in random_access_file_reader for Read and ReadAsync API to take into account the read latency for async prefetching. It also fixes ERROR_HANDLER_AUTORESUME_RETRY_COUNT stat whose value was incorrect in portal.h Pull Request resolved: https://github.com/facebook/rocksdb/pull/9810 Test Plan: Update unit test Reviewed By: anand1976 Differential Revision: D35433081 Pulled By: akankshamahajan15 fbshipit-source-id: aeec3901270e58a003ce6b5214bd25ddcb3a12a9	3 years ago
Akanksha Mahajan	36bc3da97f	Fix segfault in FilePrefetchBuffer with async_io enabled (#9777) ... Summary: If FilePrefetchBuffer object is destroyed and then later Poll() calls callback on object which has been destroyed, it gives segfault on accessing destroyed object. It was caught after adding unit tests that tests Posix implementation of ReadAsync and Poll APIs. This PR also updates and fixes existing IOURing tests which were not running locally because RocksDbIOUringEnable function wasn't defined and IOUring was disabled for those tests Pull Request resolved: https://github.com/facebook/rocksdb/pull/9777 Test Plan: Added new unit test Reviewed By: anand1976 Differential Revision: D35254002 Pulled By: akankshamahajan15 fbshipit-source-id: 68e80054ffb14ae25c255920ebc6548ca5f130a1	3 years ago
SGZW	f68706409d	Fix typo about file/sst_file_manager_impl.h (#9799) ... Summary: Fix typo deletition-> deletion Pull Request resolved: https://github.com/facebook/rocksdb/pull/9799 Reviewed By: ajkr Differential Revision: D35341617 Pulled By: jay-zhuang fbshipit-source-id: 32bc384b99e5564f6a673076c6a4f160ee6c2e46	3 years ago
bbkot	e55018a8ce	fixing issue #8345 RocksDB does not work when using UNC network paths (#9384) ... Summary: Fix https://github.com/facebook/rocksdb/issues/8345 RocksDB does not work with network filesystem paths on Windows, e.g. "\\hostname\folder\..." Pull Request resolved: https://github.com/facebook/rocksdb/pull/9384 Reviewed By: mrambacher Differential Revision: D33830622 Pulled By: riversand963 fbshipit-source-id: 2a99dc3c94415eb1460e110784b97d71600218f1	3 years ago
Akanksha Mahajan	33f8a08af2	Fix some errors in async prefetching in FilePrefetchBuffer (#9734) ... Summary: In ReadOption `async_io` which prefetches the data asynchronously, db_bench and db_stress runs were failing because wrong data was prefetched which resulted in Error: Checksum mismatched. Wrong data was copied because capacity was less than actual size needed. It has been fixed in this PR. Since there are two separate methods for async and sync prefetching, these changes are in async prefetching methods and any changes would not effect normal prefetching. I ran the regressions to make sure normal prefetching is fine. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9734 Test Plan: 1. CircleCI jobs 2. Ran db_bench ``` . /db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 -async_io=1 -adaptive_readahead=1 ``` 3. Ran db_stress test ``` export CRASH_TEST_EXT_ARGS=" --async_io=1 --adaptive_readahead=1" make crash_test -j ``` 4. Run regressions for async_io disabled. Old flow without any async changes: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.0 Date: Thu Mar 17 13:11:34 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 483618.390 micros/op 2 ops/sec; 338.9 MB/s (249 of 249 found) ``` With async prefetching changes and async_io disabled to make sure in normal prefetching there is no regression. ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 --async_io=0 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.1 Date: Wed Mar 23 15:56:37 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 481819.816 micros/op 2 ops/sec; 340.2 MB/s (250 of 250 found) ``` Reviewed By: riversand963 Differential Revision: D35058471 Pulled By: akankshamahajan15 fbshipit-source-id: 9233a1e6d97cea0c7a8111bfb9e8ac3251c341ce	3 years ago
Akanksha Mahajan	49a10feb21	Provide implementation to prefetch data asynchronously in FilePrefetchBuffer (#9674) ... Summary: In FilePrefetchBuffer if reads are sequential, after prefetching call ReadAsync API to prefetch data asynchronously so that in next prefetching data will be available. Data prefetched asynchronously will be readahead_size/2. It uses two buffers, one for synchronous prefetching and one for asynchronous. In case, the data is overlapping, the data is copied from both buffers to third buffer to make it continuous. This feature is under ReadOptions::async_io and is under experimental. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9674 Test Plan: 1. Add new unit tests 2. Run **db_stress** to make sure nothing crashes. - Normal prefetch without `async_io` ran successfully: ``` export CRASH_TEST_EXT_ARGS=" --async_io=0" make crash_test -j ``` 3. **Run Regressions**. i) Main branch without any change for normal prefetching with async_io disabled: ``` ./db_bench -db=/tmp/prefix_scan_prefetch_main -benchmarks="fillseq" -key_size=32 -value_size=512 -num=5000000 - use_direct_io_for_flush_and_compaction=true -target_file_size_base=16777216 ``` ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.0 Date: Thu Mar 17 13:11:34 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_main] seekrandom : 483618.390 micros/op 2 ops/sec; 338.9 MB/s (249 of 249 found) ``` ii) normal prefetching after changes with async_io disable: ``` ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_withchange -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 Initializing RocksDB Options from the specified file Initializing RocksDB Options from command-line flags RocksDB: version 7.0 Date: Thu Mar 17 14:11:31 2022 CPU: 24 * Intel Core Processor (Broadwell) CPUCache: 16384 KB Keys: 32 bytes each (+ 0 bytes user-defined timestamp) Values: 512 bytes each (256 bytes after compression) Entries: 5000000 Prefix: 0 bytes Keys per prefix: 0 RawSize: 2594.0 MB (estimated) FileSize: 1373.3 MB (estimated) Write rate: 0 bytes/second Read rate: 0 ops/second Compression: Snappy Compression sampling rate: 0 Memtablerep: SkipListFactory Perf Level: 1 ------------------------------------------------ DB path: [/tmp/prefix_scan_prefetch_withchange] seekrandom : 471347.227 micros/op 2 ops/sec; 348.1 MB/s (255 of 255 found) ``` Reviewed By: anand1976 Differential Revision: D34731543 Pulled By: akankshamahajan15 fbshipit-source-id: 8e23aa93453d5fe3c672b9231ad582f60207937f	3 years ago
Jay Zhuang	f0fca81fc6	Deflake DeleteSchedulerTest.StartBGEmptyTrashMultipleTimes (#9706) ... Summary: The designed sync point may not be hit if trash file is generated faster than deleting. Then the file will be deleted directly instead of waiting for background trash empty thread to do it. Increase SstFileManager Trash/DB ratio to avoid that. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9706 Test Plan: `gtest-parallel ./delete_scheduler_test --gtest_filter=DeleteSchedulerTest.StartBGEmptyTrashMultipleTimes -r 10000 -w 100` It was likely to happen on one of the host. Reviewed By: riversand963 Differential Revision: D34964735 Pulled By: jay-zhuang fbshipit-source-id: bb78015489b5f6b3f11783aae7e5853ea197702c	3 years ago
Hui Xiao	ca0ef54f16	Rate-limit automatic WAL flush after each user write (#9607) ... Summary: **Context:** WAL flush is currently not rate-limited by `Options::rate_limiter`. This PR is to provide rate-limiting to auto WAL flush, the one that automatically happen after each user write operation (i.e, `Options::manual_wal_flush == false`), by adding `WriteOptions::rate_limiter_options`. Note that we are NOT rate-limiting WAL flush that do NOT automatically happen after each user write, such as `Options::manual_wal_flush == true + manual FlushWAL()` (rate-limiting multiple WAL flushes), for the benefits of: - being consistent with [ReadOptions::rate_limiter_priority](https://github.com/facebook/rocksdb/blob/7.0.fb/include/rocksdb/options.h#L515) - being able to turn off some WAL flush's rate-limiting but not all (e.g, turn off specific the WAL flush of a critical user write like a service's heartbeat) `WriteOptions::rate_limiter_options` only accept `Env::IO_USER` and `Env::IO_TOTAL` currently due to an implementation constraint. - The constraint is that we currently queue parallel writes (including WAL writes) based on FIFO policy which does not factor rate limiter priority into this layer's scheduling. If we allow lower priorities such as `Env::IO_HIGH/MID/LOW` and such writes specified with lower priorities occurs before ones specified with higher priorities (even just by a tiny bit in arrival time), the former would have blocked the latter, leading to a "priority inversion" issue and contradictory to what we promise for rate-limiting priority. Therefore we only allow `Env::IO_USER` and `Env::IO_TOTAL` right now before improving that scheduling. A pre-requisite to this feature is to support operation-level rate limiting in `WritableFileWriter`, which is also included in this PR. **Summary:** - Renamed test suite `DBRateLimiterTest to DBRateLimiterOnReadTest` for adding a new test suite - Accept `rate_limiter_priority` in `WritableFileWriter`'s private and public write functions - Passed `WriteOptions::rate_limiter_options` to `WritableFileWriter` in the path of automatic WAL flush. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9607 Test Plan: - Added new unit test to verify existing flush/compaction rate-limiting does not break, since `DBTest, RateLimitingTest` is disabled and current db-level rate-limiting tests focus on read only (e.g, `db_rate_limiter_test`, `DBTest2, RateLimitedCompactionReads`). - Added new unit test `DBRateLimiterOnWriteWALTest, AutoWalFlush` - `strace -ftt -e trace=write ./db_bench -benchmarks=fillseq -db=/dev/shm/testdb -rate_limit_auto_wal_flush=1 -rate_limiter_bytes_per_sec=15 -rate_limiter_refill_period_us=1000000 -write_buffer_size=100000000 -disable_auto_compactions=1 -num=100` - verified that WAL flush(i.e, system-call _write_) were chunked into 15 bytes and each _write_ was roughly 1 second apart - verified the chunking disappeared when `-rate_limit_auto_wal_flush=0` - crash test: `python3 tools/db_crashtest.py blackbox --disable_wal=0 --rate_limit_auto_wal_flush=1 --rate_limiter_bytes_per_sec=10485760 --interval=10` killed as normal **Benchmarked on flush/compaction to ensure no performance regression:** - compaction with rate-limiting (see table 1, avg over 1280-run): pre-change: **915635 micros/op**; post-change: **907350 micros/op (improved by 0.106%)** ``` #!/bin/bash TEST_TMPDIR=/dev/shm/testdb START=1 NUM_DATA_ENTRY=8 N=10 rm -f compact_bmk_output.txt compact_bmk_output_2.txt dont_care_output.txt for i in $(eval echo "{$START..$NUM_DATA_ENTRY}") do NUM_RUN=$(($N*(2**($i-1)))) for j in $(eval echo "{$START..$NUM_RUN}") do ./db_bench --benchmarks=fillrandom -db=$TEST_TMPDIR -disable_auto_compactions=1 -write_buffer_size=6710886 > dont_care_output.txt && ./db_bench --benchmarks=compact -use_existing_db=1 -db=$TEST_TMPDIR -level0_file_num_compaction_trigger=1 -rate_limiter_bytes_per_sec=100000000 | egrep 'compact' done > compact_bmk_output.txt && awk -v NUM_RUN=$NUM_RUN '{sum+=$3;sum_sqrt+=$3^2}END{print sum/NUM_RUN, sqrt(sum_sqrt/NUM_RUN-(sum/NUM_RUN)^2)}' compact_bmk_output.txt >> compact_bmk_output_2.txt done ``` - compaction w/o rate-limiting (see table 2, avg over 640-run): pre-change: **822197 micros/op**; post-change: **823148 micros/op (regressed by 0.12%)** ``` Same as above script, except that -rate_limiter_bytes_per_sec=0 ``` - flush with rate-limiting (see table 3, avg over 320-run, run on the [patch](ee5c6023a9) to augment current db_bench ): pre-change: **745752 micros/op**; post-change: **745331 micros/op (regressed by 0.06 %)** ``` #!/bin/bash TEST_TMPDIR=/dev/shm/testdb START=1 NUM_DATA_ENTRY=8 N=10 rm -f flush_bmk_output.txt flush_bmk_output_2.txt for i in $(eval echo "{$START..$NUM_DATA_ENTRY}") do NUM_RUN=$(($N*(2**($i-1)))) for j in $(eval echo "{$START..$NUM_RUN}") do ./db_bench -db=$TEST_TMPDIR -write_buffer_size=1048576000 -num=1000000 -rate_limiter_bytes_per_sec=100000000 -benchmarks=fillseq,flush | egrep 'flush' done > flush_bmk_output.txt && awk -v NUM_RUN=$NUM_RUN '{sum+=$3;sum_sqrt+=$3^2}END{print sum/NUM_RUN, sqrt(sum_sqrt/NUM_RUN-(sum/NUM_RUN)^2)}' flush_bmk_output.txt >> flush_bmk_output_2.txt done ``` - flush w/o rate-limiting (see table 4, avg over 320-run, run on the [patch](ee5c6023a9) to augment current db_bench): pre-change: **487512 micros/op**, post-change: **485856 micors/ops (improved by 0.34%)** ``` Same as above script, except that -rate_limiter_bytes_per_sec=0 ``` | table 1 - compact with rate-limiting| #-run | (pre-change) avg micros/op | std micros/op | (post-change) avg micros/op | std micros/op | change in avg micros/op (%) -- | -- | -- | -- | -- | -- 10 | 896978 | 16046.9 | 901242 | 15670.9 | 0.475373978 20 | 893718 | 15813 | 886505 | 17544.7 | -0.8070778478 40 | 900426 | 23882.2 | 894958 | 15104.5 | -0.6072681153 80 | 906635 | 21761.5 | 903332 | 23948.3 | -0.3643141948 160 | 898632 | 21098.9 | 907583 | 21145 | 0.9960695813 3.20E+02 | 905252 | 22785.5 | 908106 | 25325.5 | 0.3152713278 6.40E+02 | 905213 | 23598.6 | 906741 | 21370.5 | 0.1688000504 **1.28E+03** | **908316** | **23533.1** | **907350** | **24626.8** | **-0.1063506533** average over #-run | 901896.25 | 21064.9625 | 901977.125 | 20592.025 | 0.008967217682 | table 2 - compact w/o rate-limiting| #-run | (pre-change) avg micros/op | std micros/op | (post-change) avg micros/op | std micros/op | change in avg micros/op (%) -- | -- | -- | -- | -- | -- 10 | 811211 | 26996.7 | 807586 | 28456.4 | -0.4468627768 20 | 815465 | 14803.7 | 814608 | 28719.7 | -0.105093413 40 | 809203 | 26187.1 | 797835 | 25492.1 | -1.404839082 80 | 822088 | 28765.3 | 822192 | 32840.4 | 0.01265071379 160 | 821719 | 36344.7 | 821664 | 29544.9 | -0.006693285661 3.20E+02 | 820921 | 27756.4 | 821403 | 28347.7 | 0.05871454135 **6.40E+02** | **822197** | **28960.6** | **823148** | **30055.1** | **0.1156657103** average over #-run | 8.18E+05 | 2.71E+04 | 8.15E+05 | 2.91E+04 | -0.25 | table 3 - flush with rate-limiting| #-run | (pre-change) avg micros/op | std micros/op | (post-change) avg micros/op | std micros/op | change in avg micros/op (%) -- | -- | -- | -- | -- | -- 10 | 741721 | 11770.8 | 740345 | 5949.76 | -0.1855144994 20 | 735169 | 3561.83 | 743199 | 9755.77 | 1.09226586 40 | 743368 | 8891.03 | 742102 | 8683.22 | -0.1703059588 80 | 742129 | 8148.51 | 743417 | 9631.58| 0.1735547324 160 | 749045 | 9757.21 | 746256 | 9191.86 | -0.3723407806 **3.20E+02** | **745752** | **9819.65** | **745331** | **9840.62** | **-0.0564530836** 6.40E+02 | 749006 | 11080.5 | 748173 | 10578.7 | -0.1112140624 average over #-run | 743741.4286 | 9004.218571 | 744117.5714 | 9090.215714 | 0.05057441238 | table 4 - flush w/o rate-limiting| #-run | (pre-change) avg micros/op | std micros/op | (post-change) avg micros/op | std micros/op | change in avg micros/op (%) -- | -- | -- | -- | -- | -- 10 | 477283 | 24719.6 | 473864 | 12379 | -0.7163464863 20 | 486743 | 20175.2 | 502296 | 23931.3 | 3.195320734 40 | 482846 | 15309.2 | 489820 | 22259.5 | 1.444352858 80 | 491490 | 21883.1 | 490071 | 23085.7 | -0.2887139108 160 | 493347 | 28074.3 | 483609 | 21211.7 | -1.973864238 **3.20E+02** | **487512** | **21401.5** | **485856** | **22195.2** | **-0.3396839462** 6.40E+02 | 490307 | 25418.6 | 485435 | 22405.2 | -0.9936631539 average over #-run | 4.87E+05 | 2.24E+04 | 4.87E+05 | 2.11E+04 | 0.00E+00 Reviewed By: ajkr Differential Revision: D34442441 Pulled By: hx235 fbshipit-source-id: 4790f13e1e5c0a95ae1d1cc93ffcf69dc6e78bdd	3 years ago
anand76	3362a730dc	Avoid usage of ReopenWritableFile in db_stress (#9649) ... Summary: The UniqueIdVerifier constructor currently calls ReopenWritableFile on the FileSystem, which might not be supported. Instead of relying on reopening the unique IDs file for writing, create a new file and copy the original contents. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9649 Test Plan: Run db_stress Reviewed By: pdillinger Differential Revision: D34572307 Pulled By: anand1976 fbshipit-source-id: 3a777908582d79dae57488d4278bad126774f698	3 years ago
Jay Zhuang	d3a2f284d9	Add Temperature info in `NewSequentialFile()` (#9499) ... Summary: Add Temperature hints information from RocksDB in API `NewSequentialFile()`. backup and checkpoint operations need to open the source files with `NewSequentialFile()`, which will have the temperature hints. Other operations are not covered. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9499 Test Plan: Added unittest Reviewed By: pdillinger Differential Revision: D34006115 Pulled By: jay-zhuang fbshipit-source-id: 568b34602b76520e53128672bd07e9d886786a2f	3 years ago
Jay Zhuang	f4b2500e12	Add last level and non-last level read statistics (#9519) ... Summary: Add last level and non-last level read statistics: ``` LAST_LEVEL_READ_BYTES, LAST_LEVEL_READ_COUNT, NON_LAST_LEVEL_READ_BYTES, NON_LAST_LEVEL_READ_COUNT, ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/9519 Test Plan: added unittest Reviewed By: siying Differential Revision: D34062539 Pulled By: jay-zhuang fbshipit-source-id: 908644c3050878b4234febdc72e3e19d89af38cd	3 years ago
Jay Zhuang	2fbc672732	Add temperature information to the event listener callbacks (#9591) ... Summary: RocksDB try to provide temperature information in the event listener callbacks. The information is not guaranteed, as some operation like backup won't have these information. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9591 Test Plan: Added unittest Reviewed By: siying, pdillinger Differential Revision: D34309339 Pulled By: jay-zhuang fbshipit-source-id: 4aca4f270f99fa49186d85d300da42594663d6d7	3 years ago
Andrew Kryczka	babe56ddba	Add rate limiter priority to ReadOptions (#9424) ... Summary: Users can set the priority for file reads associated with their operation by setting `ReadOptions::rate_limiter_priority` to something other than `Env::IO_TOTAL`. Rate limiting `VerifyChecksum()` and `VerifyFileChecksums()` is the motivation for this PR, so it also includes benchmarks and minor bug fixes to get that working. `RandomAccessFileReader::Read()` already had support for rate limiting compaction reads. I changed that rate limiting to be non-specific to compaction, but rather performed according to the passed in `Env::IOPriority`. Now the compaction read rate limiting is supported by setting `rate_limiter_priority = Env::IO_LOW` on its `ReadOptions`. There is no default value for the new `Env::IOPriority` parameter to `RandomAccessFileReader::Read()`. That means this PR goes through all callers (in some cases multiple layers up the call stack) to find a `ReadOptions` to provide the priority. There are TODOs for cases I believe it would be good to let user control the priority some day (e.g., file footer reads), and no TODO in cases I believe it doesn't matter (e.g., trace file reads). The API doc only lists the missing cases where a file read associated with a provided `ReadOptions` cannot be rate limited. For cases like file ingestion checksum calculation, there is no API to provide `ReadOptions` or `Env::IOPriority`, so I didn't count that as missing. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9424 Test Plan: - new unit tests - new benchmarks on ~50MB database with 1MB/s read rate limit and 100ms refill interval; verified with strace reads are chunked (at 0.1MB per chunk) and spaced roughly 100ms apart. - setup command: `./db_bench -benchmarks=fillrandom,compact -db=/tmp/testdb -target_file_size_base=1048576 -disable_auto_compactions=true -file_checksum=true` - benchmarks command: `strace -ttfe pread64 ./db_bench -benchmarks=verifychecksum,verifyfilechecksums -use_existing_db=true -db=/tmp/testdb -rate_limiter_bytes_per_sec=1048576 -rate_limit_bg_reads=1 -rate_limit_user_ops=true -file_checksum=true` - crash test using IO_USER priority on non-validation reads with https://github.com/facebook/rocksdb/issues/9567 reverted: `python3 tools/db_crashtest.py blackbox --max_key=1000000 --write_buffer_size=524288 --target_file_size_base=524288 --level_compaction_dynamic_level_bytes=true --duration=3600 --rate_limit_bg_reads=true --rate_limit_user_ops=true --rate_limiter_bytes_per_sec=10485760 --interval=10` Reviewed By: hx235 Differential Revision: D33747386 Pulled By: ajkr fbshipit-source-id: a2d985e97912fba8c54763798e04f006ccc56e0c	3 years ago
Yanqin Jin	dd203ed604	Disallow a combination of options (#9348) ... Summary: Disallow `immutable_db_opts.use_direct_io_for_flush_and_compaction == true` and `mutable_db_opts.writable_file_max_buffer_size == 0`, since it causes `WritableFileWriter::Append()` to loop forever and does not make much sense in direct IO. This combination of options itself does not make much sense: asking RocksDB to do direct IO but not allowing RocksDB to allocate a buffer. We should detect this false combination and warn user early, no matter whether the application is running on a platform that supports direct IO or not. In the case of platform **not** supporting direct IO, it's ok if the user learns about this and then finds that direct IO is not supported. One tricky thing: the constructor of `WritableFileWriter` is being used in our unit tests, and it's impossible to return status code from constructor. Since we do not throw, I put an assertion for now. Fortunately, the constructor is not exposed to external applications. Closing https://github.com/facebook/rocksdb/issues/7109 Pull Request resolved: https://github.com/facebook/rocksdb/pull/9348 Test Plan: make check Reviewed By: ajkr Differential Revision: D33371924 Pulled By: riversand963 fbshipit-source-id: 2a3701ab541cee23bffda8a36cdf37b2d235edfa	3 years ago
anand76	beb86addeb	Fix race condition in SstFileManagerImpl error recovery code (#9435) ... Summary: There is a race in SstFileManagerImpl between the ClearError() function and CancelErrorRecovery(). The race can cause ClearError() to deref the file system pointer after it has been freed. This is likely to occur during process shutdown, when the order of destruction of the DB/Env/FileSystem and SstFileManagerImpl is not deterministic. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9435 Test Plan: Reproduce the crash in a TSAN build by introducing sleeps in the code, and verify with the fix. Reviewed By: siying Differential Revision: D33774696 Pulled By: anand1976 fbshipit-source-id: 643d3da31b8d2ee6d9b6db5d33327e0053ce3b83	3 years ago
Yanqin Jin	08721293ea	Fix a bug causing duplicate trailing entries in WritableFile (buffered IO) (#9236) ... Summary: `db_stress` is a user of `FaultInjectionTestFS`. After injecting a write error, `db_stress` probabilistically determins data drop (https://github.com/facebook/rocksdb/blob/6.27.fb/db_stress_tool/db_stress_test_base.cc#L2615:L2619). In some of our recent runs of `db_stress`, we found duplicate trailing entries corresponding to file trivial move in the MANIFEST, causing the recovery to fail, because the file move operation is not idempotent: you cannot delete a file from a given level twice. Investigation suggests that data buffering in both `WritableFileWriter` and `FaultInjectionTestFS` may be the root cause. WritableFileWriter buffers data to write in a memory buffer, `WritableFileWriter::buf_`. After each `WriteBuffered()`/`WriteBufferedWithChecksum()` succeeds, the `buf_` is cleared. If the underlying file `WritableFileWriter::writable_file_` is opened in buffered IO mode, then `FaultInjectionTestFS` buffers data written for each file until next file sync. After an injected error, user of `FaultInjectionFS` can choose to drop some or none of previously buffered data. If `db_stress` does not drop any unsynced data, then such data will still exist in the `FaultInjectionTestFS`'s buffer. Existing implementation of `WritableileWriter::WriteBuffered()` does not clear `buf_` if there is an error. This may lead to the data being buffered two copies: one in `WritableFileWriter`, and another in `FaultInjectionTestFS`. We also know that the `WritableFileWriter` of MANIFEST file will close upon an error. During `Close()`, it will flush the content in `buf_`. If no write error is injected to `FaultInjectionTestFS` this time, then we end up with two copies of the data appended to the file. To fix, we clear the `WritableFileWriter::buf_` upon failure as well. We focus this PR on files opened in non-direct mode. This PR includes a unit test to reproduce a case when write error injection to `WritableFile` can cause duplicate trailing entries. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9236 Test Plan: make check Reviewed By: zhichao-cao Differential Revision: D33033984 Pulled By: riversand963 fbshipit-source-id: ebfa5a0db8cbf1ed73100528b34fcba543c5db31	3 years ago