rocksdb

Commit Graph

Author	SHA1	Message	Date
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 ``` In 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
Alan Paxton	b6ad0d958f	Fb 9718 verify checksums is ignored (#9767 ) Summary: Fixes https://github.com/facebook/rocksdb/issues/9718 The verify_checksums flag of read_options should be passed to the read options used by the BlockFetcher in a couple of cases where it is not at present. It will now happen (but did not, previously) on iteration and on [multi]get, where a fetcher is created as part of the iterate/get call. This may result in much better performance in a few workloads where the client chooses to remove verification. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9767 Reviewed By: mrambacher Differential Revision: D35218986 Pulled By: jay-zhuang fbshipit-source-id: 329d29764bb70fbc7f2673440bc46c107a813bc8	3 years ago
mrambacher	13ae16c315	Cleanup includes in dbformat.h (#8930 ) Summary: This header file was including everything and the kitchen sink when it did not need to. This resulted in many places including this header when they needed other pieces instead. Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing. Hopefully, this sort of code hygiene cleanup will speed up the builds... Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930 Reviewed By: pdillinger Differential Revision: D31142788 Pulled By: mrambacher fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d	3 years ago
anand76	8ea0a2c1bd	Parallelize secondary cache lookup in MultiGet (#8405 ) Summary: Implement the ```WaitAll()``` interface in ```LRUCache``` to allow callers to issue multiple lookups in parallel and wait for all of them to complete. Modify ```MultiGet``` to use this to parallelize the secondary cache lookups in order to reduce the overall latency. A call to ```cache->Lookup()``` returns a handle that has an incomplete value (nullptr), and the caller can call ```cache->IsReady()``` to check whether the lookup is complete, and pass a vector of handles to ```WaitAll``` to wait for completion. If any of the lookups fail, ```MultiGet``` will read the block from the SST file. Another change in this PR is to rename ```SecondaryCacheHandle``` to ```SecondaryCacheResultHandle``` as it more accurately describes the return result of the secondary cache lookup, which is more like a future. Tests: 1. Add unit tests in lru_cache_test 2. Benchmark results with no secondary cache configured Master - ``` readrandom : 41.175 micros/op 388562 ops/sec; 106.7 MB/s (7277999 of 7277999 found) readrandom : 41.217 micros/op 388160 ops/sec; 106.6 MB/s (7274999 of 7274999 found) multireadrandom : 10.309 micros/op 1552082 ops/sec; (28908992 of 28908992 found) multireadrandom : 10.321 micros/op 1550218 ops/sec; (29081984 of 29081984 found) ``` This PR - ``` readrandom : 41.158 micros/op 388723 ops/sec; 106.8 MB/s (7290999 of 7290999 found) readrandom : 41.185 micros/op 388463 ops/sec; 106.7 MB/s (7287999 of 7287999 found) multireadrandom : 10.277 micros/op 1556801 ops/sec; (29346944 of 29346944 found) multireadrandom : 10.253 micros/op 1560539 ops/sec; (29274944 of 29274944 found) ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/8405 Reviewed By: zhichao-cao Differential Revision: D29190509 Pulled By: anand1976 fbshipit-source-id: 6f8eff6246712af8a297cfe22ea0d1c3b2a01bb0	4 years ago
mrambacher	0ca6d6297f	Rename variables in ImmutableCFOptions to avoid conflicts with ImmutableDBOptions (#8227 ) Summary: Renaming ImmutableCFOptions::info_log and statistics to logger and stats. This is stage 2 in creating an ImmutableOptions class. It is necessary because the names match those in ImmutableOptions and have different types. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8227 Reviewed By: jay-zhuang Differential Revision: D28000967 Pulled By: mrambacher fbshipit-source-id: 3bf2aa04e8f1e8724d825b7deacf41080c14420b	4 years ago
Anand Ananthabhotla	9a5886bd8c	Extend Get/MultiGet deadline support to table open (#6982 ) Summary: Current implementation of the ```read_options.deadline``` option only checks the deadline for random file reads during point lookups. This PR extends the checks to file opens, prefetches and preloads as part of table open. The main changes are in the ```BlockBasedTable```, partitioned index and filter readers, and ```TableCache``` to take ReadOptions as an additional parameter. In ```BlockBasedTable::Open```, in order to retain existing behavior w.r.t checksum verification and block cache usage, we filter out most of the options in ```ReadOptions``` except ```deadline```. However, having the ```ReadOptions``` gives us more flexibility to honor other options like verify_checksums, fill_cache etc. in the future. Additional changes in callsites due to function signature changes in ```NewTableReader()``` and ```FilePrefetchBuffer```. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6982 Test Plan: Add new unit tests in db_basic_test Reviewed By: riversand963 Differential Revision: D22219515 Pulled By: anand1976 fbshipit-source-id: 8a3b92f4a889808013838603aa3ca35229cd501b	5 years ago
sdong	fdf882ded2	Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433 ) Summary: When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433 Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag. Differential Revision: D19977691 fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e	5 years ago
sdong	e8263dbdaa	Apply formatter to recent 200+ commits. (#5830 ) Summary: Further apply formatter to more recent commits. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5830 Test Plan: Run all existing tests. Differential Revision: D17488031 fbshipit-source-id: 137458fd94d56dd271b8b40c522b03036943a2ab	5 years ago
Levi Tamasi	df8c307d63	Revert to storing UncompressionDicts in the cache (#5645 ) Summary: PR https://github.com/facebook/rocksdb/issues/5584 decoupled the uncompression dictionary object from the underlying block data; however, this defeats the purpose of the digested ZSTD dictionary, since the whole point of the digest is to create it once and reuse it over and over again. This patch goes back to storing the uncompression dictionary itself in the cache (which should be now safe to do, since it no longer includes a Statistics pointer), while preserving the rest of the refactoring. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5645 Test Plan: make asan_check Differential Revision: D16551864 Pulled By: ltamasi fbshipit-source-id: 2a7e2d34bb16e70e3c816506d5afe1d842057800	5 years ago
Levi Tamasi	d92a59b6f2	Fix regression affecting partitioned indexes/filters when cache_index_and_filter_blocks is false (#5705 ) Summary: PR https://github.com/facebook/rocksdb/issues/5298 (and subsequent related patches) unintentionally changed the semantics of cache_index_and_filter_blocks: historically, this option only affected the main index/filter block; with the changes, it affects index/filter partitions as well. This can cause performance issues when cache_index_and_filter_blocks is false since in this case, partitions are neither cached nor preloaded (i.e. they are loaded on demand upon each access). The patch reverts to the earlier behavior, that is, partitions are cached similarly to data blocks regardless of the value of the above option. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5705 Test Plan: make check ./db_bench -benchmarks=fillrandom --statistics --stats_interval_seconds=1 --duration=30 --num=500000000 --bloom_bits=20 --partition_index_and_filters=true --cache_index_and_filter_blocks=false ./db_bench -benchmarks=readrandom --use_existing_db --statistics --stats_interval_seconds=1 --duration=10 --num=500000000 --bloom_bits=20 --partition_index_and_filters=true --cache_index_and_filter_blocks=false --cache_size=8000000000 Relevant statistics from the readrandom benchmark with the old code: rocksdb.block.cache.index.miss COUNT : 0 rocksdb.block.cache.index.hit COUNT : 0 rocksdb.block.cache.index.add COUNT : 0 rocksdb.block.cache.index.bytes.insert COUNT : 0 rocksdb.block.cache.index.bytes.evict COUNT : 0 rocksdb.block.cache.filter.miss COUNT : 0 rocksdb.block.cache.filter.hit COUNT : 0 rocksdb.block.cache.filter.add COUNT : 0 rocksdb.block.cache.filter.bytes.insert COUNT : 0 rocksdb.block.cache.filter.bytes.evict COUNT : 0 With the new code: rocksdb.block.cache.index.miss COUNT : 2500 rocksdb.block.cache.index.hit COUNT : 42696 rocksdb.block.cache.index.add COUNT : 2500 rocksdb.block.cache.index.bytes.insert COUNT : 4050048 rocksdb.block.cache.index.bytes.evict COUNT : 0 rocksdb.block.cache.filter.miss COUNT : 2500 rocksdb.block.cache.filter.hit COUNT : 4550493 rocksdb.block.cache.filter.add COUNT : 2500 rocksdb.block.cache.filter.bytes.insert COUNT : 10331040 rocksdb.block.cache.filter.bytes.evict COUNT : 0 Differential Revision: D16817382 Pulled By: ltamasi fbshipit-source-id: 28a516b0da1f041a03313e0b70b28cf5cf205d00	5 years ago
Levi Tamasi	092f417037	Move the uncompression dictionary object out of the block cache (#5584 ) Summary: RocksDB has historically stored uncompression dictionary objects in the block cache as opposed to storing just the block contents. This neccesitated evicting the object upon table close. With the new code, only the raw blocks are stored in the cache, eliminating the need for eviction. In addition, the patch makes the following improvements: 1) Compression dictionary blocks are now prefetched/pinned similarly to index/filter blocks. 2) A copy operation got eliminated when the uncompression dictionary is retrieved. 3) Errors related to retrieving the uncompression dictionary are propagated as opposed to silently ignored. Note: the patch temporarily breaks the compression dictionary evicition stats. They will be fixed in a separate phase. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5584 Test Plan: make asan_check Differential Revision: D16344151 Pulled By: ltamasi fbshipit-source-id: 2962b295f5b19628f9da88a3fcebbce5a5017a7b	5 years ago

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