1306 Commits (babe56ddbaae13877c896ac8d544c00d9219a374)

Author	SHA1	Message	Date
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
Peter Dillinger	1e403a0c6c	Fix assertion failure in FastLocalBloomBitsBuilder (#9585) ... Summary: As in ``` db_stress: table/block_based/filter_policy.cc:316: rocksdb::{anonymous}::FastLocalBloomBitsBuilder::FastLocalBloomBitsBuilder(int, std::atomic<long int>*, std::shared_ptr<rocksdb::CacheReservationManager>, bool): Assertion `millibits_per_key >= 1000' failed. ``` This assertion failure was actually happening with our RibbonFilterPolicy which falls back to Bloom for some cases, often for flush, but was missing new special logic to skip generating filter for 0 bits per key case. Fixed by adding the logic in other builtin FilterPolicy implementations. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9585 Test Plan: Updated db_bloom_filter_test to do more integration testing of the RibbonFilterPolicy ("auto Ribbon") class, incl regression test this with SkipFilterOnEssentiallyZeroBpk Reviewed By: ajkr Differential Revision: D34295101 Pulled By: pdillinger fbshipit-source-id: 3488eb207fc1d67bbbd1301313714aa1b6406e6e	3 years ago
Peter Dillinger	8c681087c7	Refactor FilterPolicies toward Customizable (#9567) ... Summary: Some changes to make it easier to make FilterPolicy customizable. Especially, create distinct classes for the different testing-only and user-facing built-in FilterPolicy modes. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9567 Test Plan: tests updated, with no intended difference in functionality tested. No difference in test performance seen as a result of moving to string-based filter type configuration. Reviewed By: mrambacher Differential Revision: D34234694 Pulled By: pdillinger fbshipit-source-id: 8a94931a9e04c3bcca863a4f524cfd064aaf0122	3 years ago
Peter Dillinger	479eb1aad6	Hide deprecated, inefficient block-based filter from public API (#9535) ... Summary: This change removes the ability to configure the deprecated, inefficient block-based filter in the public API. Options that would have enabled it now use "full" (and optionally partitioned) filters. Existing block-based filters can still be read and used, and a "back door" way to build them still exists, for testing and in case of trouble. About the only way this removal would cause an issue for users is if temporary memory for filter construction greatly increases. In HISTORY.md we suggest a few possible mitigations: partitioned filters, smaller SST files, or setting reserve_table_builder_memory=true. Or users who have customized a FilterPolicy using the CreateFilter/KeyMayMatch mechanism removed in https://github.com/facebook/rocksdb/issues/9501 will have to upgrade their code. (It's long past time for people to move to the new builder/reader customization interface.) This change also introduces some internal-use-only configuration strings for testing specific filter implementations while bypassing some compatibility / intelligence logic. This is intended to hint at a path toward making FilterPolicy Customizable, but it also gives us a "back door" way to configure block-based filter. Aside: updated db_bench so that -readonly implies -use_existing_db Pull Request resolved: https://github.com/facebook/rocksdb/pull/9535 Test Plan: Unit tests updated. Specifically, * BlockBasedTableTest.BlockReadCountTest is tweaked to validate the back door configuration interface and ignoring of `use_block_based_builder`. * BlockBasedTableTest.TracingGetTest is migrated from testing block-based filter access pattern to full filter access patter, by re-ordering some things. * Options test (pretty self-explanatory) Performance test - create with `./db_bench -db=/dev/shm/rocksdb1 -bloom_bits=10 -cache_index_and_filter_blocks=1 -benchmarks=fillrandom -num=10000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0` with and without `-use_block_based_filter`, which creates a DB with 21 SST files in L0. Read with `./db_bench -db=/dev/shm/rocksdb1 -readonly -bloom_bits=10 -cache_index_and_filter_blocks=1 -benchmarks=readrandom -num=10000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -duration=30` Without -use_block_based_filter: readrandom 464 ops/sec, 689280 KB DB With -use_block_based_filter: readrandom 169 ops/sec, 690996 KB DB No consistent difference with fillrandom Reviewed By: jay-zhuang Differential Revision: D34153871 Pulled By: pdillinger fbshipit-source-id: 31f4a933c542f8f09aca47fa64aec67832a69738	3 years ago
Peter Dillinger	68a9c186d0	FilterPolicy API changes for 7.0 (#9501) ... Summary: * Inefficient block-based filter is no longer customizable in the public API, though (for now) can still be enabled. * Removed deprecated FilterPolicy::CreateFilter() and FilterPolicy::KeyMayMatch() * Removed `rocksdb_filterpolicy_create()` from C API * Change meaning of nullptr return from GetBuilderWithContext() from "use block-based filter" to "generate no filter in this case." This is a cleaner solution to the proposal in https://github.com/facebook/rocksdb/issues/8250. * Also, when user specifies bits_per_key < 0.5, we now round this down to "no filter" because we expect a filter with >= 80% FP rate is unlikely to be worth the CPU cost of accessing it (esp with cache_index_and_filter_blocks=1 or partition_filters=1). * bits_per_key >= 0.5 and < 1.0 is still rounded up to 1.0 (for 62% FP rate) * This also gives us some support for configuring filters from OPTIONS file as currently saved: `filter_policy=rocksdb.BuiltinBloomFilter`. Opening from such an options file will enable reading filters (an improvement) but not writing new ones. (See Customizable follow-up below.) * Also removed deprecated functions * FilterBitsBuilder::CalculateNumEntry() * FilterPolicy::GetFilterBitsBuilder() * NewExperimentalRibbonFilterPolicy() * Remove default implementations of * FilterBitsBuilder::EstimateEntriesAdded() * FilterBitsBuilder::ApproximateNumEntries() * FilterPolicy::GetBuilderWithContext() * Remove support for "filter_policy=experimental_ribbon" configuration string. * Allow "filter_policy=bloomfilter:n" without bool to discourage use of block-based filter. Some pieces for https://github.com/facebook/rocksdb/issues/9389 Likely follow-up (later PRs): * Refactoring toward FilterPolicy Customizable, so that we can generate filters with same configuration as before when configuring from options file. * Remove support for user enabling block-based filter (ignore `bool use_block_based_builder`) * Some months after this change, we could even remove read support for block-based filter, because it is not critical to DB data preservation. * Make FilterBitsBuilder::FinishV2 to avoid `using FilterBitsBuilder::Finish` mess and add support for specifying a MemoryAllocator (for cache warming) Pull Request resolved: https://github.com/facebook/rocksdb/pull/9501 Test Plan: A number of obsolete tests deleted and new tests or test cases added or updated. Reviewed By: hx235 Differential Revision: D34008011 Pulled By: pdillinger fbshipit-source-id: a39a720457c354e00d5b59166b686f7f59e392aa	3 years ago
satyajanga	036bbab6f7	Use the comparator from the sst file table properties in sst_dump_tool (#9491) ... Summary: We introduced a new Comparator for timestamp in user keys. In the sst_dump_tool by default we use BytewiseComparator to read sst files. This change allows us to read comparator_name from table properties in meta data block and use it to read. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9491 Test Plan: added unittests for new functionality. make check   Reviewed By: riversand963 Differential Revision: D33993614 Pulled By: satyajanga fbshipit-source-id: 4b5cf938e6d2cb3931d763bef5baccc900b8c536	3 years ago
Hui Xiao	920386f2b7	Detect (new) Bloom/Ribbon Filter construction corruption (#9342) ... Summary: Note: rebase on and merge after https://github.com/facebook/rocksdb/pull/9349, https://github.com/facebook/rocksdb/pull/9345, (optional) https://github.com/facebook/rocksdb/pull/9393 **Context:** (Quoted from pdillinger) Layers of information during new Bloom/Ribbon Filter construction in building block-based tables includes the following: a) set of keys to add to filter b) set of hashes to add to filter (64-bit hash applied to each key) c) set of Bloom indices to set in filter, with duplicates d) set of Bloom indices to set in filter, deduplicated e) final filter and its checksum This PR aims to detect corruption (e.g, unexpected hardware/software corruption on data structures residing in the memory for a long time) from b) to e) and leave a) as future works for application level. - b)'s corruption is detected by verifying the xor checksum of the hash entries calculated as the entries accumulate before being added to the filter. (i.e, `XXPH3FilterBitsBuilder::MaybeVerifyHashEntriesChecksum()`) - c) - e)'s corruption is detected by verifying the hash entries indeed exists in the constructed filter by re-querying these hash entries in the filter (i.e, `FilterBitsBuilder::MaybePostVerify()`) after computing the block checksum (except for PartitionFilter, which is done right after each `FilterBitsBuilder::Finish` for impl simplicity - see code comment for more). For this stage of detection, we assume hash entries are not corrupted after checking on b) since the time interval from b) to c) is relatively short IMO. Option to enable this feature of detection is `BlockBasedTableOptions::detect_filter_construct_corruption` which is false by default. **Summary:** - Implemented new functions `XXPH3FilterBitsBuilder::MaybeVerifyHashEntriesChecksum()` and `FilterBitsBuilder::MaybePostVerify()` - Ensured hash entries, final filter and banding and their [cache reservation ](https://github.com/facebook/rocksdb/issues/9073) are released properly despite corruption - See [Filter.construction.artifacts.release.point.pdf ](https://github.com/facebook/rocksdb/files/7923487/Design.Filter.construction.artifacts.release.point.pdf) for high-level design - Bundled and refactored hash entries's related artifact in XXPH3FilterBitsBuilder into `HashEntriesInfo` for better control on lifetime of these artifact during `SwapEntires`, `ResetEntries` - Ensured RocksDB block-based table builder calls `FilterBitsBuilder::MaybePostVerify()` after constructing the filter by `FilterBitsBuilder::Finish()` - When encountering such filter construction corruption, stop writing the filter content to files and mark such a block-based table building non-ok by storing the corruption status in the builder. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9342 Test Plan: - Added new unit test `DBFilterConstructionCorruptionTestWithParam.DetectCorruption` - Included this new feature in `DBFilterConstructionReserveMemoryTestWithParam.ReserveMemory` as this feature heavily touch ReserveMemory's impl - For fallback case, I run `./filter_bench -impl=3 -detect_filter_construct_corruption=true -reserve_table_builder_memory=true -strict_capacity_limit=true -quick -runs 10 | grep 'Build avg'` to make sure nothing break. - Added to `filter_bench`: increased filter construction time by **30%**, mostly by `MaybePostVerify()` - FastLocalBloom - Before change: `./filter_bench -impl=2 -quick -runs 10 | grep 'Build avg'`: **28.86643s** - After change: - `./filter_bench -impl=2 -detect_filter_construct_corruption=false -quick -runs 10 | grep 'Build avg'` (expect a tiny increase due to MaybePostVerify is always called regardless): **27.6644s (-4% perf improvement might be due to now we don't drop bloom hash entry in `AddAllEntries` along iteration but in bulk later, same with the bypassing-MaybePostVerify case below)** - `./filter_bench -impl=2 -detect_filter_construct_corruption=true -quick -runs 10 | grep 'Build avg'` (expect acceptable increase): **34.41159s (+20%)** - `./filter_bench -impl=2 -detect_filter_construct_corruption=true -quick -runs 10 | grep 'Build avg'` (by-passing MaybePostVerify, expect minor increase): **27.13431s (-6%)** - Standard128Ribbon - Before change: `./filter_bench -impl=3 -quick -runs 10 | grep 'Build avg'`: **122.5384s** - After change: - `./filter_bench -impl=3 -detect_filter_construct_corruption=false -quick -runs 10 | grep 'Build avg'` (expect a tiny increase due to MaybePostVerify is always called regardless - verified by removing MaybePostVerify under this case and found only +-1ns difference): **124.3588s (+2%)** - `./filter_bench -impl=3 -detect_filter_construct_corruption=true -quick -runs 10 | grep 'Build avg'`(expect acceptable increase): **159.4946s (+30%)** - `./filter_bench -impl=3 -detect_filter_construct_corruption=true -quick -runs 10 | grep 'Build avg'`(by-passing MaybePostVerify, expect minor increase) : **125.258s (+2%)** - Added to `db_stress`: `make crash_test`, `./db_stress --detect_filter_construct_corruption=true` - Manually smoke-tested: manually corrupted the filter construction in some db level tests with basic PUT and background flush. As expected, the error did get returned to users in subsequent PUT and Flush status. Reviewed By: pdillinger Differential Revision: D33746928 Pulled By: hx235 fbshipit-source-id: cb056426be5a7debc1cd16f23bc250f36a08ca57	3 years ago
Peter Dillinger	f6d7ec1d02	Ignore `total_order_seek` in DB::Get (#9427) ... Summary: Apparently setting total_order_seek=true for DB::Get was intended to allow accurate read semantics if the current prefix extractor doesn't match what was used to generate SST files on disk. But since prefix_extractor was made a mutable option in 5.14.0, we have been able to detect this case and provide the correct semantics regardless of the total_order_seek option. Since that time, the option has only made Get() slower in a reasonably common case: prefix_extractor unchanged and whole_key_filtering=false. So this change primarily removes unnecessary effect of total_order_seek on Get. Also cleans up some related comments. Also adds a -total_order_seek option to db_bench and canonicalizes handling of ReadOptions in db_bench so that command line options have the expected association with library features. (There is potential for change in regression test behavior, but the old behavior is likely indefensible, or some other inconsistency would need to be fixed.) TODO in follow-up work: there should be no reason for Get() to depend on current prefix extractor at all. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9427 Test Plan: Unit tests updated. Performance (using db_bench update) Create DB with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12 -whole_key_filtering=0` Test with and without `-total_order_seek` on `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=readrandom -num=10000000 -duration=40 -disable_wal=1 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12` Before this change, total_order_seek=false: 25188 ops/sec Before this change, total_order_seek=true: 1222 ops/sec (~20x slower) After this change, total_order_seek=false: 24570 ops/sec After this change, total_order_seek=true: 25012 ops/sec (indistinguishable) Reviewed By: siying Differential Revision: D33753458 Pulled By: pdillinger fbshipit-source-id: bf892f34907a5e407d9c40bd4d42f0adbcbe0014	3 years ago
Peter Dillinger	ea89c77f27	Fix major bug with MultiGet, DeleteRange, and memtable Bloom (#9453) ... Summary: MemTable::MultiGet was not considering range tombstones before querying Bloom filter. This means range tombstones would be skipped for keys (or prefixes) with no other entries in the memtable. This could cause old values for a key (in SST files) to still show up until the range tombstone covering it has been flushed. This is fixed by essentially disabling the memtable Bloom filter when there are any range tombstones. (This could be better optimized in the future, but good enough for now.) Did some other cleanup/optimization in the same code to (more than) offset the cost of checking on range tombstones in more cases. There is now notable improvement when memtable_whole_key_filtering and prefix_extractor are used together (unusual), and this makes MultiGet closer to the Get implementation. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9453 Test Plan: new unit test added. Added memtable Bloom to crash test. Performance testing -------------------- Build WAL-only DB (recovers to memtable): ``` TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=1000000 -write_buffer_size=250000000 ``` Query test command, to maximize sensitivity to the changed code: ``` TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=multireadrandom -num=10000000 -write_buffer_size=250000000 -memtable_bloom_size_ratio=0.015 -multiread_batched -batch_size=24 -threads=8 -memtable_whole_key_filtering=$MWKF -prefix_size=$PXS ``` (Note -num here is 10x larger for mostly memtable misses) Before & after run simultaneously, average over 10 iterations per data point, ops/sec. MWKF=0 PXS=0 (Bloom disabled) Before: 5724844 After: 6722066 MWKF=0 PXS=7 (prefixes hardly unique; Bloom not useful) Before: 9981319 After: 10237990 MWKF=0 PXS=8 (prefixes unique; Bloom useful) Before: 12081715 After: 12117603 MWKF=1 PXS=0 (whole key Bloom useful) Before: 11944354 After: 12096085 MWKF=1 PXS=7 (whole key Bloom useful in new version; prefixes not useful in old version) Before: 9444299 After: 11826029 MWKF=1 PXS=7 (whole key Bloom useful in new version; prefixes useful in old version) Before: 11784465 After: 11778591 Only in this last case is the 'before' *slightly* faster, perhaps because hashing prefixes is slightly faster than hashing whole keys. Otherwise, 'after' is faster. Reviewed By: ajkr Differential Revision: D33805025 Pulled By: pdillinger fbshipit-source-id: 597523cae4f4eafdf6ae6bb2bc6cb46f83b017bf	3 years ago
Hui Xiao	11d7329503	Clarify status-handling logic in BlockBasedTableBuilder::WriteRawBlock (#9393) ... Summary: **Context:** Inside `BlockBasedTableBuilder::WriteRawBlock`, there are multiple places that change local variables `io_s` and `s` while depend on them. This PR attempts to clarify the relevant logics so that it's easier to read and add places of changing these local variables later (like https://github.com/facebook/rocksdb/pull/9342.) without changing the current behavior. **Summary:** - Shorten the lifetime of local var `io_s` and `s` as much as possible to avoid if-else branches by early return **Test** - Reasoned against original behavior to verify new changes do not break existing behaviors. - Rely on CI tests since we are not changing current behavior. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9393 Reviewed By: pdillinger Differential Revision: D33626095 Pulled By: hx235 fbshipit-source-id: 6184d1e1d85d2650d16617c449971988d062ed3f	3 years ago
sdong	5d10a53b42	Not try to finish index builder after errors (#9426) ... Summary: Right now, when error happens in block based table reader, we still call index_builder->Finish(), this causes one assertion in one stress test: db_stress: table/block_based/index_builder.cc:202: virtual rocksdb::Status rocksdb::PartitionedIndexBuilder::Finish(rocksdb::IndexBuilder::IndexBlocks*, const rocksdb::BlockHandle&): Assertion `sub_index_builder_ == nullptr' failed. This unlikely causes any corruption as we would finally abandon the file, but the code is confusing and it is hard to understand what would happen. Changing the behavior. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9426 Test Plan: Run existing tests Reviewed By: pdillinger Differential Revision: D33751929 fbshipit-source-id: 3c916b9444a4171010fc53df40496570bef5ae7a	3 years ago
Peter Dillinger	fc9d4071f0	Fast path for detecting unchanged prefix_extractor (#9407) ... Summary: Fixes a major performance regression in 6.26, where extra CPU is spent in SliceTransform::AsString when reads involve a prefix_extractor (Get, MultiGet, Seek). Common case performance is now better than 6.25. This change creates a "fast path" for verifying that the current prefix extractor is unchanged and compatible with what was used to generate a table file. This fast path detects the common case by pointer comparison on the current prefix_extractor and a "known good" prefix extractor (if applicable) that is saved at the time the table reader is opened. The "known good" prefix extractor is saved as another shared_ptr copy (in an existing field, however) to ensure the pointer is not recycled. When the prefix_extractor has changed to a different instance but same compatible configuration (rare, odd), performance is still a regression compared to 6.25, but this is likely acceptable because of the oddity of such a case. The performance of incompatible prefix_extractor is essentially unchanged. Also fixed a minor case (ForwardIterator) where a prefix_extractor could be used via a raw pointer after being freed as a shared_ptr, if replaced via SetOptions. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9407 Test Plan: ## Performance Populate DB with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12` Running head-to-head comparisons simultaneously with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=seekrandom -num=10000000 -duration=20 -disable_wal=1 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12` Below each is compared by ops/sec vs. baseline which is version 6.25 (multiple baseline runs because of variable machine load) v6.26: 4833 vs. 6698 (<- major regression!) v6.27: 4737 vs. 6397 (still) New: 6704 vs. 6461 (better than baseline in common case) Disabled fastpath: 4843 vs. 6389 (e.g. if prefix extractor instance changes but is still compatible) Changed prefix size (no usable filter) in new: 787 vs. 5927 Changed prefix size (no usable filter) in new & baseline: 773 vs. 784 Reviewed By: mrambacher Differential Revision: D33677812 Pulled By: pdillinger fbshipit-source-id: 571d9711c461fb97f957378a061b7e7dbc4d6a76	3 years ago
Peter Dillinger	ffe1e4b820	Make some FilterPolicy deprecations more clear (#9403) ... Summary: The old block-based filter has been deprecated for years, but this makes that more clear by marking the functions specific to it and logging a warning when the feature is used. It is deprecated because of performance. In that old design, you have to binary search through the full SST index before a bloom filter query, which is much more expensive than a bloom query itself. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9403 Test Plan: Used db_bench with and without -use_block_based_filter, running at the same time TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom,readrandom -num=10000000 -duration=20 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 No significant difference in construction time but 3x slower readrandom with -use_block_based_filter: readrandom : 100.517 micros/op 9948 ops/sec; 1.1 MB/s vs. readrandom : 33.368 micros/op 29968 ops/sec; 3.3 MB/s Also saw deprecation message (just once) in LOG only with -use_block_based_filter Reviewed By: ajkr Differential Revision: D33673202 Pulled By: pdillinger fbshipit-source-id: 99f6f0eff619408d9e5f7ef546954ed0be6c7a5b	3 years ago
Si Ke	93b1de4f45	Enable db_test running in Centos 32 bit OS and Alpine 32 bit OS (#9294) ... Summary: Closes https://github.com/facebook/rocksdb/issues/9271 Pull Request resolved: https://github.com/facebook/rocksdb/pull/9294 Reviewed By: riversand963, hx235 Differential Revision: D33586002 Pulled By: pdillinger fbshipit-source-id: 3d1a2fa71023e108613ff03dbd37a5f954fc4920	3 years ago
mrambacher	1973fcba11	Restore Regex support for ObjectLibrary::Register, rename new APIs to allow old one to be deprecated in the future (#9362) ... Summary: In order to support old-style regex function registration, restored the original "Register<T>(string, Factory)" method using regular expressions. The PatternEntry methods were left in place but renamed to AddFactory. The goal is to allow for the deprecation of the original regex Registry method in an upcoming release. Added modes to the PatternEntry kMatchZeroOrMore and kMatchAtLeastOne to match * or +, respectively (kMatchAtLeastOne was the original behavior). Pull Request resolved: https://github.com/facebook/rocksdb/pull/9362 Reviewed By: pdillinger Differential Revision: D33432562 Pulled By: mrambacher fbshipit-source-id: ed88ab3f9a2ad0d525c7bd1692873f9bb3209d02	3 years ago
Hui Xiao	9110685e8c	Release cache reservation of hash entries of the fall-back Ribbon Filter earlier (#9345) ... Summary: Note: rebase on and merge after https://github.com/facebook/rocksdb/pull/9349, as part of https://github.com/facebook/rocksdb/pull/9342 **Context:** https://github.com/facebook/rocksdb/pull/9073 charged the hash entries' memory in block cache with `CacheReservationHandle`. However, in the edge case where Ribbon Filter falls back to Bloom Filter and swaps its hash entries to the embedded bloom filter object, the handles associated with those entries are not swapped and thus not released as soon as those entries are cleared during Bloom Filter's finish process. Although this is a minor issue since RocksDB internal calls `FilterBitsBuilder->Reset()` right after `FilterBitsBuilder->Finish()` on the main path, which releases all the cache reservation related to both the Ribbon Filter and its embedded Bloom Filter, it still worths this fix to avoid confusion. **Summary:** - Swapped the `CacheReservationHandle` associated with the hash entries on Ribbon Filter's fallback Pull Request resolved: https://github.com/facebook/rocksdb/pull/9345 Test Plan: - Added a unit test to verify the number of cache reservation after clearing hash entries, which failed before the change and now succeeds Reviewed By: pdillinger Differential Revision: D33377225 Pulled By: hx235 fbshipit-source-id: 7487f4c40dfb6ee7928232021f93ef2c5329cffa	3 years ago
Hui Xiao	fb0a76a9e2	Always check previous conditionally unchecked status due to shortcut evaluation in BlockBasedTableBuilder::WriteIndexBlock (#9349) ... Summary: Note: part of https://github.com/facebook/rocksdb/pull/9342 **Context/Summary:** Due to shortcut evaluation in `ok() && s.IsIncomplete()`, status `s` remains unchecked if `ok()==false`, which is the case in https://app.circleci.com/pipelines/github/facebook/rocksdb/10718/workflows/429f7ad4-6b9a-446b-b9b3-710d51b90409/jobs/265508 revealed by the change in the corresponding PR https://github.com/facebook/rocksdb/pull/9342. As suggested by reviewers, separation and clarification of status checking for partitioned index building from general table building status is added. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9349 Test Plan: - The newly added if-else code is an equivalent translation of the existing logic plus always checking the conditionally unchecked status so relying on existing tests should be fine - https://github.com/facebook/rocksdb/pull/9342's `[build-linux-shared_lib-alt_namespace-status_checked](https://app.circleci.com/pipelines/github/facebook/rocksdb/10721/workflows/a200efe0-d545-4075-8c42-26dd3dc00f27/jobs/265625)` test should now pass after rebasing on this change Reviewed By: pdillinger Differential Revision: D33377223 Pulled By: hx235 fbshipit-source-id: cb81da9709ae9185e9cea89776e3012e915d6ef9	3 years ago
mrambacher	1c39b7952b	Remove/Reduce use of Regex in ObjectRegistry/Library (#9264) ... Summary: Added new ObjectLibrary::Entry classes to replace/reduce the use of Regex. For simple factories that only do name matching, there are "StringEntry" and "AltStringEntry" classes. For classes that use some semblance of regular expressions, there is a PatternEntry class that can match a name and prefixes. There is also a class for Customizable::IndividualId format matches. Added tests for the new derivative classes and got all unit tests to pass. Resolves https://github.com/facebook/rocksdb/issues/9225. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9264 Reviewed By: pdillinger Differential Revision: D33062001 Pulled By: mrambacher fbshipit-source-id: c2d2143bd2d38bdf522705c8280c35381b135c03	3 years ago
mrambacher	9a116ab4b4	Add NewMetaDataIterator method (#8692) ... Summary: Fixes a problem where the iterator for metadata was being treated as a non-user key when in fact it was a user key. This led to a problem where the property keys could not be searched for correctly. The main exposure of this problem was that the HashIndexReader could not get the "prefixes" property correctly, resulting in the failure of retrieval/creation of the BlockPrefixIndex. Added BlockBasedTableTest.SeekMetaBlocks test to validate this condition. Fixing this condition exposed two other tests (SeekWithPrefixLongerThanKey, MultiGetPrefixFilter) that passed incorrectly previously and now failed. Updated those two tests to pass. Not sure if the tests are functionally correct/still appropriate, but made them pass... Pull Request resolved: https://github.com/facebook/rocksdb/pull/8692 Reviewed By: riversand963 Differential Revision: D33119539 Pulled By: mrambacher fbshipit-source-id: 658969fe9265f73dc184dab97cc3f4eaed2d881a	3 years ago
mrambacher	423538a816	Make MemoryAllocator into a Customizable class (#8980) ... Summary: - Make MemoryAllocator and its implementations into a Customizable class. - Added a "DefaultMemoryAllocator" which uses new and delete - Added a "CountedMemoryAllocator" that counts the number of allocs and free - Updated the existing tests to use these new allocators - Changed the memkind allocator test into a generic test that can test the various allocators. - Added tests for creating all of the allocators - Added tests to verify/create the JemallocNodumpAllocator using its options. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8980 Reviewed By: zhichao-cao Differential Revision: D32990403 Pulled By: mrambacher fbshipit-source-id: 6fdfe8218c10dd8dfef34344a08201be1fa95c76	3 years ago
Peter Dillinger	0050a73a4f	New stable, fixed-length cache keys (#9126) ... Summary: This change standardizes on a new 16-byte cache key format for block cache (incl compressed and secondary) and persistent cache (but not table cache and row cache). The goal is a really fast cache key with practically ideal stability and uniqueness properties without external dependencies (e.g. from FileSystem). A fixed key size of 16 bytes should enable future optimizations to the concurrent hash table for block cache, which is a heavy CPU user / bottleneck, but there appears to be measurable performance improvement even with no changes to LRUCache. This change replaces a lot of disjointed and ugly code handling cache keys with calls to a simple, clean new internal API (cache_key.h). (Preserving the old cache key logic under an option would be very ugly and likely negate the performance gain of the new approach. Complete replacement carries some inherent risk, but I think that's acceptable with sufficient analysis and testing.) The scheme for encoding new cache keys is complicated but explained in cache_key.cc. Also: EndianSwapValue is moved to math.h to be next to other bit operations. (Explains some new include "math.h".) ReverseBits operation added and unit tests added to hash_test for both. Fixes https://github.com/facebook/rocksdb/issues/7405 (presuming a root cause) Pull Request resolved: https://github.com/facebook/rocksdb/pull/9126 Test Plan: ### Basic correctness Several tests needed updates to work with the new functionality, mostly because we are no longer relying on filesystem for stable cache keys so table builders & readers need more context info to agree on cache keys. This functionality is so core, a huge number of existing tests exercise the cache key functionality. ### Performance Create db with `TEST_TMPDIR=/dev/shm ./db_bench -bloom_bits=10 -benchmarks=fillrandom -num=3000000 -partition_index_and_filters` And test performance with `TEST_TMPDIR=/dev/shm ./db_bench -readonly -use_existing_db -bloom_bits=10 -benchmarks=readrandom -num=3000000 -duration=30 -cache_index_and_filter_blocks -cache_size=250000 -threads=4` using DEBUG_LEVEL=0 and simultaneous before & after runs. Before ops/sec, avg over 100 runs: 121924 After ops/sec, avg over 100 runs: 125385 (+2.8%) ### Collision probability I have built a tool, ./cache_bench -stress_cache_key to broadly simulate host-wide cache activity over many months, by making some pessimistic simplifying assumptions: * Every generated file has a cache entry for every byte offset in the file (contiguous range of cache keys) * All of every file is cached for its entire lifetime We use a simple table with skewed address assignment and replacement on address collision to simulate files coming & going, with quite a variance (super-Poisson) in ages. Some output with `./cache_bench -stress_cache_key -sck_keep_bits=40`: ``` Total cache or DBs size: 32TiB Writing 925.926 MiB/s or 76.2939TiB/day Multiply by 9.22337e+18 to correct for simulation losses (but still assume whole file cached) ``` These come from default settings of 2.5M files per day of 32 MB each, and `-sck_keep_bits=40` means that to represent a single file, we are only keeping 40 bits of the 128-bit cache key. With file size of 2\*\*25 contiguous keys (pessimistic), our simulation is about 2\*\*(128-40-25) or about 9 billion billion times more prone to collision than reality. More default assumptions, relatively pessimistic: * 100 DBs in same process (doesn't matter much) * Re-open DB in same process (new session ID related to old session ID) on average every 100 files generated * Restart process (all new session IDs unrelated to old) 24 times per day After enough data, we get a result at the end: ``` (keep 40 bits) 17 collisions after 2 x 90 days, est 10.5882 days between (9.76592e+19 corrected) ``` If we believe the (pessimistic) simulation and the mathematical generalization, we would need to run a billion machines all for 97 billion days to expect a cache key collision. To help verify that our generalization ("corrected") is robust, we can make our simulation more precise with `-sck_keep_bits=41` and `42`, which takes more running time to get enough data: ``` (keep 41 bits) 16 collisions after 4 x 90 days, est 22.5 days between (1.03763e+20 corrected) (keep 42 bits) 19 collisions after 10 x 90 days, est 47.3684 days between (1.09224e+20 corrected) ``` The generalized prediction still holds. With the `-sck_randomize` option, we can see that we are beating "random" cache keys (except offsets still non-randomized) by a modest amount (roughly 20x less collision prone than random), which should make us reasonably comfortable even in "degenerate" cases: ``` 197 collisions after 1 x 90 days, est 0.456853 days between (4.21372e+18 corrected) ``` I've run other tests to validate other conditions behave as expected, never behaving "worse than random" unless we start chopping off structured data. Reviewed By: zhichao-cao Differential Revision: D33171746 Pulled By: pdillinger fbshipit-source-id: f16a57e369ed37be5e7e33525ace848d0537c88f	3 years ago
Akanksha Mahajan	96d0773a11	Update prepopulate_block_cache logic to support block-based filter (#9300) ... Summary: Update prepopulate_block_cache logic to support block-based filter during insertion in block cache Pull Request resolved: https://github.com/facebook/rocksdb/pull/9300 Test Plan: CircleCI tests, make crash_test -j64 Reviewed By: pdillinger Differential Revision: D33132018 Pulled By: akankshamahajan15 fbshipit-source-id: 241deabab8645bda704728e572d6de6354df18b2	3 years ago
Peter Dillinger	e92a0ed040	Optimize & clean up footer code (#9280) ... Summary: Again, ahead of planned changes in https://github.com/facebook/rocksdb/issues/9058. This change improves performance (vs. pre-https://github.com/facebook/rocksdb/issues/9240 baseline) by separating a FooterBuilder from Footer, where FooterBuilder includes (inline owns) the serialized data so that it can be stack allocated. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9280 Test Plan: existing tests + performance testing below Extreme case performance testing as in https://github.com/facebook/rocksdb/issues/9240 with TEST_TMPDIR=/dev/shm/ ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=30000000 (Each is ops/s averaged over 50 runs, run simultaneously with competing configuration for load fairness) Pre-https://github.com/facebook/rocksdb/issues/9240 baseline (f577458): 436389 With https://github.com/facebook/rocksdb/issues/9240 (653c392): 417946 (-4.2% vs. baseline) This change: 443762 (+1.7% vs. baseline) Reviewed By: ajkr Differential Revision: D33077220 Pulled By: pdillinger fbshipit-source-id: 7eaa6499589aac1693414a758e8c799216c5016c	3 years ago
Peter Dillinger	653c392e47	More refactoring ahead of footer & meta changes (#9240) ... Summary: I'm working on a new format_version=6 to support context checksum (https://github.com/facebook/rocksdb/issues/9058) and this includes much of the refactoring and test updates to support that change. Test coverage data and manual inspection agree on dead code in block_based_table_reader.cc (removed). Pull Request resolved: https://github.com/facebook/rocksdb/pull/9240 Test Plan: tests enhanced to cover more cases etc. Extreme case performance testing indicates small % regression in fillseq (w/ compaction), though CPU profile etc. doesn't suggest any explanation. There is enhanced correctness checking in Footer::DecodeFrom, but this should be negligible. TEST_TMPDIR=/dev/shm/ ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=30000000 -checksum_type=1 --disable_wal={false,true} (Each is ops/s averaged over 50 runs, run simultaneously with competing configuration for load fairness) Before w/ wal: 454512 After w/ wal: 444820 (-2.1%) Before w/o wal: 1004560 After w/o wal: 998897 (-0.6%) Since this doesn't modify WAL code, one would expect real effects to be larger in w/o wal case. This regression will be corrected in a follow-up PR. Reviewed By: ajkr Differential Revision: D32813769 Pulled By: pdillinger fbshipit-source-id: 444a244eabf3825cd329b7d1b150cddce320862f	3 years ago
Akanksha Mahajan	9e4d56f2c9	Fix segmentation fault in table_options.prepopulate_block_cache when used with partition_filters (#9263) ... Summary: When table_options.prepopulate_block_cache is set to BlockBasedTableOptions::PrepopulateBlockCache::kFlushOnly and table_options.partition_filters is also set true, then there is segmentation failure when top level filter is fetched because its entered with wrong type in cache. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9263 Test Plan: Updated unit tests; Ran db_stress: make crash_test -j32 Reviewed By: pdillinger Differential Revision: D32936566 Pulled By: akankshamahajan15 fbshipit-source-id: 8bd79e53830d3e3c1bb79787e1ffbc3cb46d4426	3 years ago
Hui Xiao	9daf07305c	Replace TableProperties::properties_offsets map with external_sst_file_global_seqno_offset (#9212) ... Summary: **Context:** Searching `TableProperties::properties_offsets` across the codebase reveals that internally it is only used to find the external SST file's global seqno offeset. Therefore we can narrow it down and replace this map property with a uint64_t property `external_sst_file_global_seqno_offset` to save memory usage related to table properties. Note: - See PR comments for discussion about potential impact on existing external usage of `TableProperties::properties_offsets` - See PR comments for discussion on keeping external SST file global seqno's offset VS using a simple flag indicating seqno's existence. **Summary:** - Replaced `TableProperties::properties_offsets` with `TableProperties::external_sst_file_global_seqno_offset` Pull Request resolved: https://github.com/facebook/rocksdb/pull/9212 Test Plan: - Relied on existing tests should be sufficient since `TableProperties::properties_offsets` existed before and should already be tested. Reviewed By: ajkr Differential Revision: D32665941 Pulled By: hx235 fbshipit-source-id: 718e44617346dc4f3b1276ee953e61c196277795	3 years ago
Akanksha Mahajan	04b2c16f9b	Fix bug in rocksdb internal automatic prefetching (#9234) ... Summary: After introducing adaptive_readahead, the original flow got broken. Readahead size was set to 0 because of which rocksdb wasn't be able to do automatic prefetching which it enables after seeing sequential reads. This PR fixes it. ---------------------------------------------------------------------------------------------------- Before this patch: b_bench -use_existing_db=true -db=/tmp/prefix_scan -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 6.27 Date: Tue Nov 30 11:56:50 2021 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 WARNING: Assertions are enabled; benchmarks unnecessarily slow ------------------------------------------------ DB path: [/tmp/prefix_scan] seekrandom : 5356367.174 micros/op 0 ops/sec; 29.4 MB/s (23 of 23 found) ---------------------------------------------------------------------------------------------------- After the patch: ./db_bench -use_existing_db=true -db=/tmp/prefix_scan -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 6.27 Date: Tue Nov 30 14:38:33 2021 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 WARNING: Assertions are enabled; benchmarks unnecessarily slow ------------------------------------------------ DB path: [/tmp/prefix_scan] seekrandom : 456504.277 micros/op 2 ops/sec; 359.8 MB/s (264 of 264 found) Pull Request resolved: https://github.com/facebook/rocksdb/pull/9234 Test Plan: Ran ./db_bench -db=/data/mysql/rocksdb/prefix_scan -benchmarks="fillseq" -key_size=32 -value_size=512 -num=5000000 -use_d irect_io_for_flush_and_compaction=true -target_file_size_base=16777216 and then ./db_bench -use_existing_db=true -db=/data/mysql/rocksdb/prefix_scan -benchmarks="seekrandom" -key_size=32 -value_siz e=512 -num=5000000 -use_direct_reads=true -seek_nexts=327680 -duration=120 -ops_between_duration_checks=1 and compared the results. Reviewed By: anand1976 Differential Revision: D32743965 Pulled By: akankshamahajan15 fbshipit-source-id: b950fba68c91963b7deb5c20acdf471bc60251f5	3 years ago
Levi Tamasi	dc5de45af8	Support readahead during compaction for blob files (#9187) ... Summary: The patch adds a new BlobDB configuration option `blob_compaction_readahead_size` that can be used to enable prefetching data from blob files during compaction. This is important when using storage with higher latencies like HDDs or remote filesystems. If enabled, prefetching is used for all cases when blobs are read during compaction, namely garbage collection, compaction filters (when the existing value has to be read from a blob file), and `Merge` (when the value of the base `Put` is stored in a blob file). Pull Request resolved: https://github.com/facebook/rocksdb/pull/9187 Test Plan: Ran `make check` and the stress/crash test. Reviewed By: riversand963 Differential Revision: D32565512 Pulled By: ltamasi fbshipit-source-id: 87be9cebc3aa01cc227bec6b5f64d827b8164f5d	3 years ago
Peter Dillinger	cd4ea675e3	Fix backward compatibility with 2.5 through 2.7 (#9189) ... Summary: A bug in https://github.com/facebook/rocksdb/issues/9163 can cause checksum verification to fail if parsing a properties block fails. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9189 Test Plan: check_format_compatible.sh (never quite works locally but this particular case seems fixed using variants of SHORT_TEST=1). And added new unit test case. Reviewed By: ajkr Differential Revision: D32574626 Pulled By: pdillinger fbshipit-source-id: 6fa5c8595737b71a3c3d011a52daf6d6c08715d7	3 years ago
slk	e12753eb71	Track each SST's timestamp information as user properties (#9093) ... Summary: Track each SST's timestamp information as user properties https://github.com/facebook/rocksdb/issues/8959 Rockdb has supported user-defined timestamp feature. Application can specify a timestamp when writing each k-v pair. When data flush from memory to disk file called SST files. Each SST files consist of multiple data blocks and several metadata blocks. Among the metadata blocks, there is one called Properties block that tracks some pre-defined properties of this SST file. This PR is for collecting the properties of min and max timestamps of all keys in the file. With those properties the SST file is more convenient to tell whether the keys in the SST have timestamps or not. The changes involved are as follows: 1) Add a class TimestampTablePropertiesCollector to collect min/max timestamp when add keys to table, The way TimestampTablePropertiesCollector use to compare timestamp of key should defined by user by implementing the Comparator::CompareTimestamp function in the user defined comparator. 2) Add corresponding unit tests. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9093 Reviewed By: ltamasi Differential Revision: D32406927 Pulled By: riversand963 fbshipit-source-id: 25922971b7e67bacf4d53a1fb67c4c5ddaa61573	3 years ago
Peter Dillinger	230660be73	Improve / clean up meta block code & integrity (#9163) ... Summary: * Checksums are now checked on meta blocks unless specifically suppressed or not applicable (e.g. plain table). (Was other way around.) This means a number of cases that were not checking checksums now are, including direct read TableProperties in Version::GetTableProperties (fixed in meta_blocks ReadTableProperties), reading any block from PersistentCache (fixed in BlockFetcher), read TableProperties in SstFileDumper (ldb/sst_dump/BackupEngine) before table reader open, maybe more. * For that to work, I moved the global_seqno+TableProperties checksum logic to the shared table/ code, because that is used by many utilies such as SstFileDumper. * Also for that to work, we have to know when we're dealing with a block that has a checksum (trailer), so added that capability to Footer based on magic number, and from there BlockFetcher. * Knowledge of trailer presence has also fixed a problem where other table formats were reading blocks including bytes for a non-existant trailer--and awkwardly kind-of not using them, e.g. no shared code checking checksums. (BlockFetcher compression type was populated incorrectly.) Now we only read what is needed. * Minimized code duplication and differing/incompatible/awkward abstractions in meta_blocks.{cc,h} (e.g. SeekTo in metaindex block without parsing block handle) * Moved some meta block handling code from table_properties*.* * Moved some code specific to block-based table from shared table/ code to BlockBasedTable class. The checksum stuff means we can't completely separate it, but things that don't need to be in shared table/ code should not be. * Use unique_ptr rather than raw ptr in more places. (Note: you can std::move from unique_ptr to shared_ptr.) Without enhancements to GetPropertiesOfAllTablesTest (see below), net reduction of roughly 100 lines of code. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9163 Test Plan: existing tests and * Enhanced DBTablePropertiesTest.GetPropertiesOfAllTablesTest to verify that checksums are now checked on direct read of table properties by TableCache (new test would fail before this change) * Also enhanced DBTablePropertiesTest.GetPropertiesOfAllTablesTest to test putting table properties under old meta name * Also generally enhanced that same test to actually test what it was supposed to be testing already, by kicking things out of table cache when we don't want them there. Reviewed By: ajkr, mrambacher Differential Revision: D32514757 Pulled By: pdillinger fbshipit-source-id: 507964b9311d186ae8d1131182290cbd97a99fa9	3 years ago
Hui Xiao	74544d582f	Account Bloom/Ribbon filter construction memory in global memory limit (#9073) ... Summary: Note: This PR is the 4th part of a bigger PR stack (https://github.com/facebook/rocksdb/pull/9073) and will rebase/merge only after the first three PRs (https://github.com/facebook/rocksdb/pull/9070, https://github.com/facebook/rocksdb/pull/9071, https://github.com/facebook/rocksdb/pull/9130) merge. **Context:** Similar to https://github.com/facebook/rocksdb/pull/8428, this PR is to track memory usage during (new) Bloom Filter (i.e,FastLocalBloom) and Ribbon Filter (i.e, Ribbon128) construction, moving toward the goal of [single global memory limit using block cache capacity](https://github.com/facebook/rocksdb/wiki/Projects-Being-Developed#improving-memory-efficiency). It also constrains the size of the banding portion of Ribbon Filter during construction by falling back to Bloom Filter if that banding is, at some point, larger than the available space in the cache under `LRUCacheOptions::strict_capacity_limit=true`. The option to turn on this feature is `BlockBasedTableOptions::reserve_table_builder_memory = true` which by default is set to `false`. We [decided](https://github.com/facebook/rocksdb/pull/9073#discussion_r741548409) not to have separate option for separate memory user in table building therefore their memory accounting are all bundled under one general option. **Summary:** - Reserved/released cache for creation/destruction of three main memory users with the passed-in `FilterBuildingContext::cache_res_mgr` during filter construction: - hash entries (i.e`hash_entries`.size(), we bucket-charge hash entries during insertion for performance), - banding (Ribbon Filter only, `bytes_coeff_rows` +`bytes_result_rows` + `bytes_backtrack`), - final filter (i.e, `mutable_buf`'s size). - Implementation details: in order to use `CacheReservationManager::CacheReservationHandle` to account final filter's memory, we have to store the `CacheReservationManager` object and `CacheReservationHandle` for final filter in `XXPH3BitsFilterBuilder` as well as explicitly delete the filter bits builder when done with the final filter in block based table. - Added option fo run `filter_bench` with this memory reservation feature Pull Request resolved: https://github.com/facebook/rocksdb/pull/9073 Test Plan: - Added new tests in `db_bloom_filter_test` to verify filter construction peak cache reservation under combination of `BlockBasedTable::Rep::FilterType` (e.g, `kFullFilter`, `kPartitionedFilter`), `BloomFilterPolicy::Mode`(e.g, `kFastLocalBloom`, `kStandard128Ribbon`, `kDeprecatedBlock`) and `BlockBasedTableOptions::reserve_table_builder_memory` - To address the concern for slow test: tests with memory reservation under `kFullFilter` + `kStandard128Ribbon` and `kPartitionedFilter` take around **3000 - 6000 ms** and others take around **1500 - 2000 ms**, in total adding **20000 - 25000 ms** to the test suit running locally - Added new test in `bloom_test` to verify Ribbon Filter fallback on large banding in FullFilter - Added test in `filter_bench` to verify that this feature does not significantly slow down Bloom/Ribbon Filter construction speed. Local result averaged over **20** run as below: - FastLocalBloom - baseline `./filter_bench -impl=2 -quick -runs 20 | grep 'Build avg'`: - **Build avg ns/key: 29.56295** (DEBUG_LEVEL=1), **29.98153** (DEBUG_LEVEL=0) - new feature (expected to be similar as above)`./filter_bench -impl=2 -quick -runs 20 -reserve_table_builder_memory=true | grep 'Build avg'`: - **Build avg ns/key: 30.99046** (DEBUG_LEVEL=1), **30.48867** (DEBUG_LEVEL=0) - new feature of RibbonFilter with fallback (expected to be similar as above) `./filter_bench -impl=2 -quick -runs 20 -reserve_table_builder_memory=true -strict_capacity_limit=true | grep 'Build avg'` : - **Build avg ns/key: 31.146975** (DEBUG_LEVEL=1), **30.08165** (DEBUG_LEVEL=0) - Ribbon128 - baseline `./filter_bench -impl=3 -quick -runs 20 | grep 'Build avg'`: - **Build avg ns/key: 129.17585** (DEBUG_LEVEL=1), **130.5225** (DEBUG_LEVEL=0) - new feature (expected to be similar as above) `./filter_bench -impl=3 -quick -runs 20 -reserve_table_builder_memory=true | grep 'Build avg' `: - **Build avg ns/key: 131.61645** (DEBUG_LEVEL=1), **132.98075** (DEBUG_LEVEL=0) - new feature of RibbonFilter with fallback (expected to be a lot faster than above due to fallback) `./filter_bench -impl=3 -quick -runs 20 -reserve_table_builder_memory=true -strict_capacity_limit=true | grep 'Build avg'` : - **Build avg ns/key: 52.032965** (DEBUG_LEVEL=1), **52.597825** (DEBUG_LEVEL=0) - And the warning message of `"Cache reservation for Ribbon filter banding failed due to cache full"` is indeed logged to console. Reviewed By: pdillinger Differential Revision: D31991348 Pulled By: hx235 fbshipit-source-id: 9336b2c60f44d530063da518ceaf56dac5f9df8e	3 years ago
Peter Dillinger	f8c685c4fc	Check for and disallow shared key space in block caches (#9172) ... Summary: We have three layers of block cache that often use the same key but map to different physical data: * BlockBasedTableOptions::block_cache * BlockBasedTableOptions::block_cache_compressed * BlockBasedTableOptions::persistent_cache If any two of these happen to share an underlying implementation and key space (insertion into one shows up in another), then memory safety is broken. The simplest case is block_cache == block_cache_compressed. (Credit mrambacher for asking about this case in a review.) With this change, we explicitly check for overlap and preemptively and safely fail with a Status code. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9172 Test Plan: test added. Crashes without new check Reviewed By: anand1976 Differential Revision: D32465659 Pulled By: pdillinger fbshipit-source-id: 3876b45b6dce6167e5a7a642725ddc86b96f8e40	3 years ago
Akanksha Mahajan	17ce1ca48b	Reuse internal auto readhead_size at each Level (expect L0) for Iterations (#9056) ... Summary: RocksDB does auto-readahead for iterators on noticing more than two sequential reads for a table file if user doesn't provide readahead_size. The readahead starts at 8KB and doubles on every additional read up to max_auto_readahead_size. However at each level, if iterator moves over next file, readahead_size starts again from 8KB. This PR introduces a new ReadOption "adaptive_readahead" which when set true will maintain readahead_size at each level. So when iterator moves from one file to another, new file's readahead_size will continue from previous file's readahead_size instead of scratch. However if reads are not sequential it will fall back to 8KB (default) with no prefetching for that block. 1. If block is found in cache but it was eligible for prefetch (block wasn't in Rocksdb's prefetch buffer), readahead_size will decrease by 8KB. 2. It maintains readahead_size for L1 - Ln levels. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9056 Test Plan: Added new unit tests Ran db_bench for "readseq, seekrandom, seekrandomwhilewriting, readrandom" with --adaptive_readahead=true and there was no regression if new feature is enabled. Reviewed By: anand1976 Differential Revision: D31773640 Pulled By: akankshamahajan15 fbshipit-source-id: 7332d16258b846ae5cea773009195a5af58f8f98	3 years ago
anand76	dddb791c18	Enable a few unit tests to use custom Env objects (#9087) ... Summary: Allow compaction_job_test, db_io_failure_test, dbformat_test, deletefile_test, and fault_injection_test to use a custom Env object. Also move ```RegisterCustomObjects``` declaration to a header file to simplify things. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9087 Test Plan: Run manually using "buck test rocksdb/src:compaction_job_test_fbcode" etc. Reviewed By: riversand963 Differential Revision: D32007222 Pulled By: anand1976 fbshipit-source-id: 99af58559e25bf61563dfa95dc46e31fa7375792	3 years ago
Hui Xiao	3018a3e27e	Minor improvement to CacheReservationManager/WriteBufferManager/CompressionDictBuilding (#9139) ... Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/9139 Reviewed By: zhichao-cao Differential Revision: D32211415 Pulled By: hx235 fbshipit-source-id: 39ce036ba34e1fb4a1992a33ac6904a4a943301d	3 years ago
Hui Xiao	1ababeb76a	Deallocate payload of BlockBasedTableBuilder::Rep::FilterBlockBuilder earlier for Full/PartitionedFilter (#9070) ... Summary: Note: This PR is the 1st part of a bigger PR stack (https://github.com/facebook/rocksdb/pull/9073). Context: Previously, the payload (i.e, filter data) within `BlockBasedTableBuilder::Rep::FilterBlockBuilder` object is not deallocated until `BlockBasedTableBuilder` is deallocated, despite it is no longer useful after its related `filter_content` being written. - Transferred the payload (i.e, the filter data) out of `BlockBasedTableBuilder::Rep::FilterBlockBuilder` object - For PartitionedFilter: - Unified `filters` and `filter_gc` lists into one `std::deque<FilterEntry> filters` by adding a new field `last_filter_entry_key` and storing the `std::unique_ptr filter_data` with the `Slice filter` in the same entry - Reset `last_filter_data` in the case where `filters` is empty, which should be as by then we would've finish using all the `Slice filter` - Deallocated the payload by going out of scope as soon as we're done with using the `filter_content` associated with the payload - This is an internal interface change at the level of `FilterBlockBuilder::Finish()`, which leads to touching the inherited interface in `BlockBasedFilterBlockBuilder`. But for that, the payload transferring is ignored. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9070 Test Plan: - The main focus is to catch segment fault error during `FilterBlockBuilder::Finish()` and `BlockBasedTableBuilder::Finish()` and interface mismatch. Relying on existing CI tests is enough as `assert(false)` was temporarily added to verify the new logic of transferring ownership indeed run Reviewed By: pdillinger Differential Revision: D31884933 Pulled By: hx235 fbshipit-source-id: f73ecfbea13788d4fc058013ace27230110b52f4	3 years ago
Peter Dillinger	dfedc74d82	Some checksum code refactoring (#9113) ... Summary: To prepare for adding checksum to footer and "context aware" checksums. This also brings closely related code much closer together. Recently added `BlockBasedTableBuilder::ComputeBlockTrailer` for testing is made obsolete in the refactoring, as testing the checksums can happen at a lower level of abstraction. Also now checking for unrecognized checksum type on reading footer, rather than later on use. Also removed an obsolete function delcaration. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9113 Test Plan: existing tests worked before refactoring to remove `ComputeBlockTrailer`. And then refactored+improved tests using it. Reviewed By: mrambacher Differential Revision: D32090149 Pulled By: pdillinger fbshipit-source-id: 2879da683c1498ea85a3b70dace9b6d9f6b47b6e	3 years ago
hx235	a5ec5e3ea0	Minor improvement to #8428 (Account for dictionary-building buffer in global memory limit) (#9032) ... Summary: Summary/Context: - Renamed `cache_rev_mng` to `compression_dict_buffer_cache_res_mgr` - It is to distinguish with other potential `cache_res_mgr` in `BlockBasedTableBuilder` and to use correct short-hand for the words "reservation", "manager" - Added `table_options.block_cache == nullptr` in additional to `table_options.no_block_cache == true` to be conditions where we don't create a `CacheReservationManager` - Theoretically `table_options.no_block_cache == true` is equivalent to `table_options.block_cache == nullptr` by API. But since segment fault will be generated by passing `nullptr` into `CacheReservationManager`'s constructor, it does not hurt to directly verify `table_options.block_cache != nullptr` before passing in - Renamed `is_cache_full` to `exceeds_global_block_cache_limit` - It is to hide implementation detail of cache reservation and to emphasize on the concept/design intent of caping memory within global block cache limit Pull Request resolved: https://github.com/facebook/rocksdb/pull/9032 Test Plan: - Passing existing tests Reviewed By: ajkr Differential Revision: D32005807 Pulled By: hx235 fbshipit-source-id: 619fd17bb924199de3db5924d8ab7dae53b1efa2	3 years ago
Peter Dillinger	a7d4bea43a	Implement XXH3 block checksum type (#9069) ... Summary: XXH3 - latest hash function that is extremely fast on large data, easily faster than crc32c on most any x86_64 hardware. In integrating this hash function, I have handled the compression type byte in a non-standard way to avoid using the streaming API (extra data movement and active code size because of hash function complexity). This approach got a thumbs-up from Yann Collet. Existing functionality change: * reject bad ChecksumType in options with InvalidArgument This change split off from https://github.com/facebook/rocksdb/issues/9058 because context-aware checksum is likely to be handled through different configuration than ChecksumType. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9069 Test Plan: tests updated, and substantially expanded. Unit tests now check that we don't accidentally change the values generated by the checksum algorithms ("schema test") and that we properly handle invalid/unrecognized checksum types in options or in file footer. DBTestBase::ChangeOptions (etc.) updated from two to one configuration changing from default CRC32c ChecksumType. The point of this test code is to detect possible interactions among features, and the likelihood of some bad interaction being detected by including configurations other than XXH3 and CRC32c--and then not detected by stress/crash test--is extremely low. Stress/crash test also updated (manual run long enough to see it accepts new checksum type). db_bench also updated for microbenchmarking checksums. ### Performance microbenchmark (PORTABLE=0 DEBUG_LEVEL=0, Broadwell processor) ./db_bench -benchmarks=crc32c,xxhash,xxhash64,xxh3,crc32c,xxhash,xxhash64,xxh3,crc32c,xxhash,xxhash64,xxh3 crc32c : 0.200 micros/op 5005220 ops/sec; 19551.6 MB/s (4096 per op) xxhash : 0.807 micros/op 1238408 ops/sec; 4837.5 MB/s (4096 per op) xxhash64 : 0.421 micros/op 2376514 ops/sec; 9283.3 MB/s (4096 per op) xxh3 : 0.171 micros/op 5858391 ops/sec; 22884.3 MB/s (4096 per op) crc32c : 0.206 micros/op 4859566 ops/sec; 18982.7 MB/s (4096 per op) xxhash : 0.793 micros/op 1260850 ops/sec; 4925.2 MB/s (4096 per op) xxhash64 : 0.410 micros/op 2439182 ops/sec; 9528.1 MB/s (4096 per op) xxh3 : 0.161 micros/op 6202872 ops/sec; 24230.0 MB/s (4096 per op) crc32c : 0.203 micros/op 4924686 ops/sec; 19237.1 MB/s (4096 per op) xxhash : 0.839 micros/op 1192388 ops/sec; 4657.8 MB/s (4096 per op) xxhash64 : 0.424 micros/op 2357391 ops/sec; 9208.6 MB/s (4096 per op) xxh3 : 0.162 micros/op 6182678 ops/sec; 24151.1 MB/s (4096 per op) As you can see, especially once warmed up, xxh3 is fastest. ### Performance macrobenchmark (PORTABLE=0 DEBUG_LEVEL=0, Broadwell processor) Test for I in `seq 1 50`; do for CHK in 0 1 2 3 4; do TEST_TMPDIR=/dev/shm/rocksdb$CHK ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=30000000 -checksum_type=$CHK 2>&1 | grep 'micros/op' | tee -a results-$CHK & done; wait; done Results (ops/sec) for FILE in results*; do echo -n "$FILE "; awk '{ s += $5; c++; } END { print 1.0 * s / c; }' < $FILE; done results-0 252118 # kNoChecksum results-1 251588 # kCRC32c results-2 251863 # kxxHash results-3 252016 # kxxHash64 results-4 252038 # kXXH3 Reviewed By: mrambacher Differential Revision: D31905249 Pulled By: pdillinger fbshipit-source-id: cb9b998ebe2523fc7c400eedf62124a78bf4b4d1	3 years ago
Peter Dillinger	5bf9a7d5ee	Clarify caching behavior for index and filter partitions (#9068) ... Summary: Somewhat confusingly, index and filter partition blocks are never owned by table readers, even with cache_index_and_filter_blocks=false. They still go into block cache (possibly pinned by table reader) if there is a block cache. If no block cache, they are only loaded transiently on demand. This PR primarily clarifies the options APIs and some internal code comments. Also, this closes a hypothetical data corruption vulnerability where some but not all index partitions are pinned. I haven't been able to reproduce a case where it can happen (the failure seems to propagate to abort table open) but it's worth patching nonetheless. Fixes https://github.com/facebook/rocksdb/issues/8979 Pull Request resolved: https://github.com/facebook/rocksdb/pull/9068 Test Plan: existing tests :-/ I could cover the new code using sync points, but then I'd have to very carefully relax my `assert(false)` Reviewed By: ajkr Differential Revision: D31898284 Pulled By: pdillinger fbshipit-source-id: f2511a7d3a36bc04b627935d8e6cfea6422f98be	3 years ago
Zhichao Cao	6d93b87588	Add lowest_used_cache_tier to ImmutableDBOptions to enable or disable Secondary Cache (#9050) ... Summary: Currently, if Secondary Cache is provided to the lru cache, it is used by default. We add CacheTier to advanced_options.h to describe the cache tier we used. Add a `lowest_used_cache_tier` option to `DBOptions` (immutable) and pass it to BlockBasedTableReader to decide if secondary cache will be used or not. By default it is `CacheTier::kNonVolatileTier`, which means, we always use both block cache (kVolatileTier) and secondary cache (kNonVolatileTier). By set it to `CacheTier::kVolatileTier`, the DB will not use the secondary cache. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9050 Test Plan: added new tests Reviewed By: anand1976 Differential Revision: D31744769 Pulled By: zhichao-cao fbshipit-source-id: a0575ebd23e1c6dfcfc2b4c8578764e73b15bce6	3 years ago
Peter Dillinger	b234a3f569	Improve data block construction performance (#9040) ... Summary: ... by bypassing tracking of last_key in BlockBuilder when last_key is already known (for BlockBasedTableBuilder::data_block). I tried extracting a base class of BlockBuilder without the last_key tracking at all, but that became complicated by NewFlushBlockPolicy() in the public API referencing BlockBuilder, which would need to be the base class, and I don't want to replace nearly all the internal references to BlockBuilder. Possible follow-up: * Investigate / consider using AddWithLastKey in more places This improvement should stack with https://github.com/facebook/rocksdb/issues/9039 Pull Request resolved: https://github.com/facebook/rocksdb/pull/9040 Test Plan: TEST_TMPDIR=/dev/shm/rocksdb1 ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=50000000 Compiled with DEBUG_LEVEL=0 Test vs. control runs simulaneous for better accuracy, units = ops/sec Run 1: 278929 vs. 267799 (+4.2%) Run 2: 281836 vs. 267432 (+5.4%) Run 3: 278279 vs. 270454 (+2.9%) (This benchmark is chosen to have detectable signal-to-noise, not to represent expected improvement percent on real workloads.) Reviewed By: mrambacher Differential Revision: D31706033 Pulled By: pdillinger fbshipit-source-id: 8a50fe6fefdd67b6d7665ffa687bbdcf5ad0d5ec	3 years ago
Peter Dillinger	ad5325a736	Experimental support for SST unique IDs (#8990) ... Summary: * New public header unique_id.h and function GetUniqueIdFromTableProperties which computes a universally unique identifier based on table properties of table files from recent RocksDB versions. * Generation of DB session IDs is refactored so that they are guaranteed unique in the lifetime of a process running RocksDB. (SemiStructuredUniqueIdGen, new test included.) Along with file numbers, this enables SST unique IDs to be guaranteed unique among SSTs generated in a single process, and "better than random" between processes. See https://github.com/pdillinger/unique_id * In addition to public API producing 'external' unique IDs, there is a function for producing 'internal' unique IDs, with functions for converting between the two. In short, the external ID is "safe" for things people might do with it, and the internal ID enables more "power user" features for the future. Specifically, the external ID goes through a hashing layer so that any subset of bits in the external ID can be used as a hash of the full ID, while also preserving uniqueness guarantees in the first 128 bits (bijective both on first 128 bits and on full 192 bits). Intended follow-up: * Use the internal unique IDs in cache keys. (Avoid conflicts with https://github.com/facebook/rocksdb/issues/8912) (The file offset can be XORed into the third 64-bit value of the unique ID.) * Publish the external unique IDs in FileStorageInfo (https://github.com/facebook/rocksdb/issues/8968) Pull Request resolved: https://github.com/facebook/rocksdb/pull/8990 Test Plan: Unit tests added, and checking of unique ids in stress test. NOTE in stress test we do not generate nearly enough files to thoroughly stress uniqueness, but the test trims off pieces of the ID to check for uniqueness so that we can infer (with some assumptions) stronger properties in the aggregate. Reviewed By: zhichao-cao, mrambacher Differential Revision: D31582865 Pulled By: pdillinger fbshipit-source-id: 1f620c4c86af9abe2a8d177b9ccf2ad2b9f48243	3 years ago
Jay Zhuang	b4326b5273	Fix gcc-11 compile error (#9043) ... Summary: gcc11 added new static check. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9043 Test Plan: Added CI for gcc11 build Reviewed By: zhichao-cao Differential Revision: D31716005 Pulled By: jay-zhuang fbshipit-source-id: 9f53be6f2f9e58e39b83359f6bbf66f945d57429	3 years ago
Peter Dillinger	9d66d6d13e	Two performance improvements in BlockBuilder (#9039) ... Summary: Primarily, this change reserves space in the std::string for building the next block once a block is finished, using `block_size` as reservation size. Note: also tried reusing same std::string in the common "unbuffered" path but that showed no benefit or regression. Secondarily, this slightly reduces the work in resetting `restarts_`. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9039 Test Plan: TEST_TMPDIR=/dev/shm/rocksdb1 ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=50000000 Compiled with DEBUG_LEVEL=0 Test vs. control runs simulaneous for better accuracy, units = ops/sec Run 1, Primary change only: 292697 vs. 280267 (+4.4%) Run 2, Primary change only: 288763 vs. 279621 (+3.3%) Run 1, Secondary change only: 260065 vs. 254232 (+2.3%) Run 2, Secondary change only: 275925 vs. 272248 (+1.4%) Run 1, Both changes: 284890 vs. 270372 (+5.3%) Run 2, Both changes: 263511 vs. 258188 (+2.0%) Reviewed By: zhichao-cao Differential Revision: D31701253 Pulled By: pdillinger fbshipit-source-id: 7e40810afbb98e6b6446955e77bda59e69b19ffd	3 years ago
leipeng	4c277ab201	MergingIterator: rearrange fields to reduce paddings (#9024) ... Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/9024 Reviewed By: pdillinger Differential Revision: D31614752 Pulled By: ajkr fbshipit-source-id: ef19ae243127f992e982a5a3b8ddefe7946246f8	3 years ago
Andrew Kryczka	c0ec58ecb9	stop populating unused/invalid MergingIterator heaps (#8975) ... Summary: I was looking at https://github.com/facebook/rocksdb/issues/2636 and got very confused that `MergingIterator::AddIterator()` is populating `min_heap_` with dangling pointers. There is justification in the comments that `min_heap_` will be cleared before it's used, but it'd be cleaner to not populate it with dangling pointers in the first place. Also made similar change in the constructor for consistency, although the pointers there would not be dangling, just unused. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8975 Test Plan: rely on existing tests Reviewed By: pdillinger, hx235 Differential Revision: D31273767 Pulled By: ajkr fbshipit-source-id: 127ca9dd1f82f77f55dd0c3f19511de3282fc229	3 years ago
Zhichao Cao	699f45049d	Introduce a mechanism to dump out blocks from block cache and re-insert to secondary cache (#8912) ... Summary: Background: Cache warming up will cause potential read performance degradation due to reading blocks from storage to the block cache. Since in production, the workload and access pattern to a certain DB is stable, it is a potential solution to dump out the blocks belonging to a certain DB to persist storage (e.g., to a file) and bulk-load the blocks to Secondary cache before the DB is relaunched. For example, when migrating a DB form host A to host B, it will take a short period of time, the access pattern to blocks in the block cache will not change much. It is efficient to dump out the blocks of certain DB, migrate to the destination host and insert them to the Secondary cache before we relaunch the DB. Design: we introduce the interface of CacheDumpWriter and CacheDumpRead for user to store the blocks dumped out from block cache. RocksDB will encode all the information and send the string to the writer. User can implement their own writer it they want. CacheDumper and CacheLoad are introduced to save the blocks and load the blocks respectively. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8912 Test Plan: add new tests to lru_cache_test and pass make check. Reviewed By: pdillinger Differential Revision: D31452871 Pulled By: zhichao-cao fbshipit-source-id: 11ab4f5d03e383f476947116361d54188d36ec48	3 years ago
mrambacher	53e595d1f3	Cleanup multiple implementations of VectorIterator (#8901) ... Summary: There were three implementations of VectorIterator (util/vector_iterator, test_util/testutil.h and LoggingForwardVectorIterator). Merged them into one class to increase code coverage/testing and reduce duplication. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8901 Reviewed By: pdillinger Differential Revision: D31022673 Pulled By: mrambacher fbshipit-source-id: 8e3acbd2dfd60b4df609d02cc72846de2389d531	3 years ago