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1444 Commits (57abdea38992350bd1d9044ddee263205a4b37f3)
Author | SHA1 | Message | Date |
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Peter Dillinger | 204fcff751 |
HyperClockCache support for SecondaryCache, with refactoring (#11301)
Summary: Internally refactors SecondaryCache integration out of LRUCache specifically and into a wrapper/adapter class that works with various Cache implementations. Notably, this relies on separating the notion of async lookup handles from other cache handles, so that HyperClockCache doesn't have to deal with the problem of allocating handles from the hash table for lookups that might fail anyway, and might be on the same key without support for coalescing. (LRUCache's hash table can incorporate previously allocated handles thanks to its pointer indirection.) Specifically, I'm worried about the case in which hundreds of threads try to access the same block and probing in the hash table degrades to linear search on the pile of entries with the same key. This change is a big step in the direction of supporting stacked SecondaryCaches, but there are obstacles to completing that. Especially, there is no SecondaryCache hook for evictions to pass from one to the next. It has been proposed that evictions be transmitted simply as the persisted data (as in SaveToCallback), but given the current structure provided by the CacheItemHelpers, that would require an extra copy of the block data, because there's intentionally no way to ask for a contiguous Slice of the data (to allow for flexibility in storage). `AsyncLookupHandle` and the re-worked `WaitAll()` should be essentially prepared for stacked SecondaryCaches, but several "TODO with stacked secondaries" issues remain in various places. It could be argued that the stacking instead be done as a SecondaryCache adapter that wraps two (or more) SecondaryCaches, but at least with the current API that would require an extra heap allocation on SecondaryCache Lookup for a wrapper SecondaryCacheResultHandle that can transfer a Lookup between secondaries. We could also consider trying to unify the Cache and SecondaryCache APIs, though that might be difficult if `AsyncLookupHandle` is kept a fixed struct. ## cache.h (public API) Moves `secondary_cache` option from LRUCacheOptions to ShardedCacheOptions so that it is applicable to HyperClockCache. ## advanced_cache.h (advanced public API) * Add `Cache::CreateStandalone()` so that the SecondaryCache support wrapper can use it. * Add `SetEvictionCallback()` / `eviction_callback_` so that the SecondaryCache support wrapper can use it. Only a single callback is supported for efficiency. If there is ever a need for more than one, hopefully that can be handled with a broadcast callback wrapper. These are essentially the two "extra" pieces of `Cache` for pulling out specific SecondaryCache support from the `Cache` implementation. I think it's a good trade-off as these are reasonable, limited, and reusable "cut points" into the `Cache` implementations. * Remove async capability from standard `Lookup()` (getting rid of awkward restrictions on pending Handles) and add `AsyncLookupHandle` and `StartAsyncLookup()`. As noted in the comments, the full struct of `AsyncLookupHandle` is exposed so that it can be stack allocated, for efficiency, though more data is being copied around than before, which could impact performance. (Lookup info -> AsyncLookupHandle -> Handle vs. Lookup info -> Handle) I could foresee a future in which a Cache internally saves a pointer to the AsyncLookupHandle, which means it's dangerous to allow it to be copyable or even movable. It also means it's not compatible with std::vector (which I don't like requiring as an API parameter anyway), so `WaitAll()` expects any contiguous array of AsyncLookupHandles. I believe this is best for common case efficiency, while behaving well in other cases also. For example, `WaitAll()` has no effect on default-constructed AsyncLookupHandles, which look like a completed cache miss. ## cacheable_entry.h A couple of functions are obsolete because Cache::Handle can no longer be pending. ## cache.cc Provides default implementations for new or revamped Cache functions, especially appropriate for non-blocking caches. ## secondary_cache_adapter.{h,cc} The full details of the Cache wrapper adding SecondaryCache support. Essentially replicates the SecondaryCache handling that was in LRUCache, but obviously refactored. There is a bit of logic duplication, where Lookup() is essentially a manually optimized version of StartAsyncLookup() and Wait(), but it's roughly a dozen lines of code. ## sharded_cache.h, typed_cache.h, charged_cache.{h,cc}, sim_cache.cc Simply updated for Cache API changes. ## lru_cache.{h,cc} Carefully remove SecondaryCache logic, implement `CreateStandalone` and eviction handler functionality. ## clock_cache.{h,cc} Expose existing `CreateStandalone` functionality, add eviction handler functionality. Light refactoring. ## block_based_table_reader* Mostly re-worked the only usage of async Lookup, which is in BlockBasedTable::MultiGet. Used arrays in place of autovector in some places for efficiency. Simplified some logic by not trying to process some cache results before they're all ready. Created new function `BlockBasedTable::GetCachePriority()` to reduce some pre-existing code duplication (and avoid making it worse). Fixed at least one small bug from the prior confusing mixture of async and sync Lookups. In MaybeReadBlockAndLoadToCache(), called by RetrieveBlock(), called by MultiGet() with wait=false, is_cache_hit for the block_cache_tracer entry would not be set to true if the handle was pending after Lookup and before Wait. ## Intended follow-up work * Figure out if there are any missing stats or block_cache_tracer work in refactored BlockBasedTable::MultiGet * Stacked secondary caches (see above discussion) * See if we can make up for the small MultiGet performance regression. * Study more performance with SecondaryCache * Items evicted from over-full LRUCache in Release were not being demoted to SecondaryCache, and still aren't to minimize unit test churn. Ideally they would be demoted, but it's an exceptional case so not a big deal. * Use CreateStandalone for cache reservations (save unnecessary hash table operations). Not a big deal, but worthy cleanup. * Somehow I got the contract for SecondaryCache::Insert wrong in #10945. (Doesn't take ownership!) That API comment needs to be fixed, but didn't want to mingle that in here. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11301 Test Plan: ## Unit tests Generally updated to include HCC in SecondaryCache tests, though HyperClockCache has some different, less strict behaviors that leads to some tests not really being set up to work with it. Some of the tests remain disabled with it, but I think we have good coverage without them. ## Crash/stress test Updated to use the new combination. ## Performance First, let's check for regression on caches without secondary cache configured. Adding support for the eviction callback is likely to have a tiny effect, but it shouldn't be worrisome. LRUCache could benefit slightly from less logic around SecondaryCache handling. We can test with cache_bench default settings, built with DEBUG_LEVEL=0 and PORTABLE=0. ``` (while :; do base/cache_bench --cache_type=hyper_clock_cache | grep Rough; done) | awk '{ sum += $9; count++; print $0; print "Average: " int(sum / count) }' ``` **Before** this and #11299 (which could also have a small effect), running for about an hour, before & after running concurrently for each cache type: HyperClockCache: 3168662 (average parallel ops/sec) LRUCache: 2940127 **After** this and #11299, running for about an hour: HyperClockCache: 3164862 (average parallel ops/sec) (0.12% slower) LRUCache: 2940928 (0.03% faster) This is an acceptable difference IMHO. Next, let's consider essentially the worst case of new CPU overhead affecting overall performance. MultiGet uses the async lookup interface regardless of whether SecondaryCache or folly are used. We can configure a benchmark where all block cache queries are for data blocks, and all are hits. Create DB and test (before and after tests running simultaneously): ``` TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=30000000 -disable_wal=1 -bloom_bits=16 TEST_TMPDIR=/dev/shm base/db_bench -benchmarks=multireadrandom[-X30] -readonly -multiread_batched -batch_size=32 -num=30000000 -bloom_bits=16 -cache_size=6789000000 -duration 20 -threads=16 ``` **Before**: multireadrandom [AVG 30 runs] : 3444202 (± 57049) ops/sec; 240.9 (± 4.0) MB/sec multireadrandom [MEDIAN 30 runs] : 3514443 ops/sec; 245.8 MB/sec **After**: multireadrandom [AVG 30 runs] : 3291022 (± 58851) ops/sec; 230.2 (± 4.1) MB/sec multireadrandom [MEDIAN 30 runs] : 3366179 ops/sec; 235.4 MB/sec So that's roughly a 3% regression, on kind of a *worst case* test of MultiGet CPU. Similar story with HyperClockCache: **Before**: multireadrandom [AVG 30 runs] : 3933777 (± 41840) ops/sec; 275.1 (± 2.9) MB/sec multireadrandom [MEDIAN 30 runs] : 3970667 ops/sec; 277.7 MB/sec **After**: multireadrandom [AVG 30 runs] : 3755338 (± 30391) ops/sec; 262.6 (± 2.1) MB/sec multireadrandom [MEDIAN 30 runs] : 3785696 ops/sec; 264.8 MB/sec Roughly a 4-5% regression. Not ideal, but not the whole story, fortunately. Let's also look at Get() in db_bench: ``` TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=readrandom[-X30] -readonly -num=30000000 -bloom_bits=16 -cache_size=6789000000 -duration 20 -threads=16 ``` **Before**: readrandom [AVG 30 runs] : 2198685 (± 13412) ops/sec; 153.8 (± 0.9) MB/sec readrandom [MEDIAN 30 runs] : 2209498 ops/sec; 154.5 MB/sec **After**: readrandom [AVG 30 runs] : 2292814 (± 43508) ops/sec; 160.3 (± 3.0) MB/sec readrandom [MEDIAN 30 runs] : 2365181 ops/sec; 165.4 MB/sec That's showing roughly a 4% improvement, perhaps because of the secondary cache code that is no longer part of LRUCache. But weirdly, HyperClockCache is also showing 2-3% improvement: **Before**: readrandom [AVG 30 runs] : 2272333 (± 9992) ops/sec; 158.9 (± 0.7) MB/sec readrandom [MEDIAN 30 runs] : 2273239 ops/sec; 159.0 MB/sec **After**: readrandom [AVG 30 runs] : 2332407 (± 11252) ops/sec; 163.1 (± 0.8) MB/sec readrandom [MEDIAN 30 runs] : 2335329 ops/sec; 163.3 MB/sec Reviewed By: ltamasi Differential Revision: D44177044 Pulled By: pdillinger fbshipit-source-id: e808e48ff3fe2f792a79841ba617be98e48689f5 |
2 years ago |
Peter Dillinger | ccaa3225b0 |
Simplify tracking entries already in SecondaryCache (#11299)
Summary: In preparation for factoring secondary cache support out of individual Cache implementations, we can get rid of the "in secondary cache" flag on entries through a workable hack: when an entry is promoted from secondary, it is inserted in primary using a helper that lacks secondary cache support, thus preventing re-insertion into secondary cache through existing logic. This adds to the complexity of building CacheItemHelpers, because you always have to be able to get to an equivalent helper without secondary cache support, but that complexity is reasonably isolated within RocksDB typed_cache.h and test code. gcc-7 seems to have problems with constexpr constructor referencing `this` so removed constexpr support on CacheItemHelper. Also refactored some related test code to share common code / functionality. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11299 Test Plan: existing tests Reviewed By: anand1976 Differential Revision: D44101453 Pulled By: pdillinger fbshipit-source-id: 7a59d0a3938ee40159c90c3e65d7004f6a272345 |
2 years ago |
Hui Xiao | bab5f9a6f2 |
Add new stat rocksdb.table.open.prefetch.tail.read.bytes, rocksdb.table.open.prefetch.tail.{miss|hit} (#11265)
Summary: **Context/Summary:** We are adding new stats to measure behavior of prefetched tail size and look up into this buffer The stat collection is done in FilePrefetchBuffer but only for prefetched tail buffer during table open for now using FilePrefetchBuffer enum. It's cleaner than the alternative of implementing in upper-level call places of FilePrefetchBuffer for table open. It also has the benefit of extensible to other types of FilePrefetchBuffer if needed. See db bench for perf regression concern. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11265 Test Plan: **- Piggyback on existing test** **- rocksdb.table.open.prefetch.tail.miss is harder to UT so I manually set prefetch tail read bytes to be small and run db bench.** ``` ./db_bench -db=/tmp/testdb -statistics=true -benchmarks="fillseq" -key_size=32 -value_size=512 -num=5000 -write_buffer_size=655 -target_file_size_base=655 -disable_auto_compactions=false -compression_type=none -bloom_bits=3 -use_direct_reads=true ``` ``` rocksdb.table.open.prefetch.tail.read.bytes P50 : 4096.000000 P95 : 4096.000000 P99 : 4096.000000 P100 : 4096.000000 COUNT : 225 SUM : 921600 rocksdb.table.open.prefetch.tail.miss COUNT : 91 rocksdb.table.open.prefetch.tail.hit COUNT : 1034 ``` **- No perf regression observed in db_bench** SETUP command: create same db with ~900 files for pre-change/post-change. ``` ./db_bench -db=/tmp/testdb -benchmarks="fillseq" -key_size=32 -value_size=512 -num=500000 -write_buffer_size=655360 -disable_auto_compactions=true -target_file_size_base=16777216 -compression_type=none ``` TEST command 60 runs or til convergence: as suggested by anand1976 and akankshamahajan15, vary `seek_nexts` and `async_io` in testing. ``` ./db_bench -use_existing_db=true -db=/tmp/testdb -statistics=false -cache_size=0 -cache_index_and_filter_blocks=false -benchmarks=seekrandom[-X60] -num=50000 -seek_nexts={10, 500, 1000} -async_io={0|1} -use_direct_reads=true ``` async io = 0, direct io read = true | seek_nexts = 10, 30 runs | seek_nexts = 500, 12 runs | seek_nexts = 1000, 6 runs -- | -- | -- | -- pre-post change | 4776 (± 28) ops/sec; 24.8 (± 0.1) MB/sec | 288 (± 1) ops/sec; 74.8 (± 0.4) MB/sec | 145 (± 4) ops/sec; 75.6 (± 2.2) MB/sec post-change | 4790 (± 32) ops/sec; 24.9 (± 0.2) MB/sec | 288 (± 3) ops/sec; 74.7 (± 0.8) MB/sec | 143 (± 3) ops/sec; 74.5 (± 1.6) MB/sec async io = 1, direct io read = true | seek_nexts = 10, 54 runs | seek_nexts = 500, 6 runs | seek_nexts = 1000, 4 runs -- | -- | -- | -- pre-post change | 3350 (± 36) ops/sec; 17.4 (± 0.2) MB/sec | 264 (± 0) ops/sec; 68.7 (± 0.2) MB/sec | 138 (± 1) ops/sec; 71.8 (± 1.0) MB/sec post-change | 3358 (± 27) ops/sec; 17.4 (± 0.1) MB/sec | 263 (± 2) ops/sec; 68.3 (± 0.8) MB/sec | 139 (± 1) ops/sec; 72.6 (± 0.6) MB/sec Reviewed By: ajkr Differential Revision: D43781467 Pulled By: hx235 fbshipit-source-id: a706a18472a8edb2b952bac3af40eec803537f2a |
2 years ago |
Levi Tamasi | 49881921cd |
Rename a recently added PerfContext counter (#11294)
Summary: The patch renames the counter added in https://github.com/facebook/rocksdb/issues/11284 for better consistency with the existing naming scheme. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11294 Test Plan: `make check` Reviewed By: jowlyzhang Differential Revision: D44035964 Pulled By: ltamasi fbshipit-source-id: 8b1a2a03ee728148365367e0ecc1fcf462f62191 |
2 years ago |
Levi Tamasi | 1d52438504 |
Add a PerfContext counter for merge operands applied in point lookups (#11284)
Summary: The existing PerfContext counter `internal_merge_count` only tracks the Merge operands applied during range scans. The patch adds a new counter called `internal_merge_count_point_lookups` to track the same metric for point lookups (`Get` / `MultiGet` / `GetEntity` / `MultiGetEntity`), and also fixes a couple of cases in the iterator where the existing counter wasn't updated. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11284 Test Plan: `make check` Reviewed By: jowlyzhang Differential Revision: D43926082 Pulled By: ltamasi fbshipit-source-id: 321566d8b4cf0a3b6c9b73b7a5c984fb9bb492e9 |
2 years ago |
Peter Dillinger | e01073252b |
Tests verifying non-zero checksums of zero bytes (#11260)
Summary: Adds unit tests verifying that a block payload and checksum of all zeros is not falsely considered valid data. The test exhaustively checks that for blocks up to some length (default 20K, more exhaustively 10M) of all zeros do not produce a block checksum of all zeros. Also small refactoring of an existing checksum test to use parameterized test. (Suggest hiding whitespace changes for review.) Pull Request resolved: https://github.com/facebook/rocksdb/pull/11260 Test Plan: this is the test, manual run with `ROCKSDB_THOROUGH_CHECKSUM_TEST=1` to verify up to 10M. Reviewed By: hx235 Differential Revision: D43706192 Pulled By: pdillinger fbshipit-source-id: 95e721c320ca928e7fa2400c2570fb359cc30b1f |
2 years ago |
Changyu Bi | d053926fa2 |
Improve documentation for MergingIterator (#11161)
Summary: Add some comments to try to explain how/why MergingIterator works. Made some small refactoring, mostly in MergingIterator::SkipNextDeleted() and MergingIterator::SeekImpl(). Pull Request resolved: https://github.com/facebook/rocksdb/pull/11161 Test Plan: crash test with small key range: ``` python3 tools/db_crashtest.py blackbox --simple --max_key=100 --interval=6000 --write_buffer_size=262144 --target_file_size_base=256 --max_bytes_for_level_base=262144 --block_size=128 --value_size_mult=33 --subcompactions=10 --use_multiget=1 --delpercent=3 --delrangepercent=2 --verify_iterator_with_expected_state_one_in=2 --num_iterations=10 ``` Reviewed By: ajkr Differential Revision: D42860994 Pulled By: cbi42 fbshipit-source-id: 3f0c1c9c6481a7f468bf79d823998907a8116e9e |
2 years ago |
Levi Tamasi | 3c9eed688e |
Enable moving a string or PinnableSlice into PinnableWideColumns (#11248)
Summary: This makes it possible to eliminate some copies in `GetEntity` / `MultiGetEntity`, in particular when `Merge`s or blobs are involved. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11248 Test Plan: `make check` Reviewed By: akankshamahajan15 Differential Revision: D43544215 Pulled By: ltamasi fbshipit-source-id: bc4c8955a24bbd8bc4ab098e72133ead757f9707 |
2 years ago |
Changyu Bi | 229297d1b8 |
Refactor AddRangeDels() + consider range tombstone during compaction file cutting (#11113)
Summary: A second attempt after https://github.com/facebook/rocksdb/issues/10802, with bug fixes and refactoring. This PR updates compaction logic to take range tombstones into account when determining whether to cut the current compaction output file (https://github.com/facebook/rocksdb/issues/4811). Before this change, only point keys were considered, and range tombstones could cause large compactions. For example, if the current compaction outputs is a range tombstone [a, b) and 2 point keys y, z, they would be added to the same file, and may overlap with too many files in the next level and cause a large compaction in the future. This PR also includes ajkr's effort to simplify the logic to add range tombstones to compaction output files in `AddRangeDels()` ([https://github.com/facebook/rocksdb/issues/11078](https://github.com/facebook/rocksdb/pull/11078#issuecomment-1386078861)). The main change is for `CompactionIterator` to emit range tombstone start keys to be processed by `CompactionOutputs`. A new class `CompactionMergingIterator` is introduced to replace `MergingIterator` under `CompactionIterator` to enable emitting of range tombstone start keys. Further improvement after this PR include cutting compaction output at some grandparent boundary key (instead of the next output key) when cutting within a range tombstone to reduce overlap with grandparents. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11113 Test Plan: * added unit test in db_range_del_test * crash test with a small key range: `python3 tools/db_crashtest.py blackbox --simple --max_key=100 --interval=600 --write_buffer_size=262144 --target_file_size_base=256 --max_bytes_for_level_base=262144 --block_size=128 --value_size_mult=33 --subcompactions=10 --use_multiget=1 --delpercent=3 --delrangepercent=2 --verify_iterator_with_expected_state_one_in=2 --num_iterations=10` Reviewed By: ajkr Differential Revision: D42655709 Pulled By: cbi42 fbshipit-source-id: 8367e36ef5640e8f21c14a3855d4a8d6e360a34c |
2 years ago |
mrambacher | b6640c3117 |
Remove FactoryFunc from LoadXXXObject (#11203)
Summary: The primary purpose of the FactoryFunc was to support LITE mode where the ObjectRegistry was not available. With the removal of LITE mode, the function was no longer required. Note that the MergeOperator had some private classes defined in header files. To gain access to their constructors (and name methods), the class definitions were moved into header files. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11203 Reviewed By: cbi42 Differential Revision: D43160255 Pulled By: pdillinger fbshipit-source-id: f3a465fd5d1a7049b73ecf31e4b8c3762f6dae6c |
2 years ago |
Andrew Kryczka | 25e1365227 |
Merge operator failed subcode (#11231)
Summary: From HISTORY.md: Added a subcode of `Status::Corruption`, `Status::SubCode::kMergeOperatorFailed`, for users to identify corruption failures originating in the merge operator, as opposed to RocksDB's internally identified data corruptions. This is a followup to https://github.com/facebook/rocksdb/issues/11092, where we gave users the ability to keep running a DB despite merge operator failing. Now that the DB keeps running despite such failures, they want to be able to distinguish such failures from real corruptions. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11231 Test Plan: updated unit test Reviewed By: akankshamahajan15 Differential Revision: D43396607 Pulled By: ajkr fbshipit-source-id: 17fbcc779ad724dafada8abd73efd38e1c5208b9 |
2 years ago |
Andrew Kryczka | 6aef1a05d6 |
Use CacheDependencies() at start of ApproximateKeyAnchors() (#11230)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/11230 Test Plan: - setup command: `$ ./db_bench -benchmarks=fillrandom,compact -compression_type=none -num=1000000 -write_buffer_size=4194304 -target_file_size_base=4194304 -use_direct_io_for_flush_and_compaction=true -partition_index_and_filters=true -bloom_bits=10 -metadata_block_size=1024` - measure small read count bucketed by size: `$ strace -fye pread64 ./db_bench.ctrl -use_existing_db=true -benchmarks=compact -compaction_readahead_size=4194304 -compression_type=none -num=1000000 -write_buffer_size=4194304 -target_file_size_base=4194304 -use_direct_io_for_flush_and_compaction=true -partition_index_and_filters=true -bloom_bits=10 -metadata_block_size=1024 -subcompactions=4 -cache_size=1048576000 2>&1 >/dev/null | awk '/= [0-9]+$/{print "[", int($NF / 1024), "KB,", int(1 + $NF / 1024), "KB)"}' | sort -n -k 2 | uniq -c | head -3` - before: ``` 1119 [ 0 KB, 1 KB) 1 [ 6 KB, 7 KB) 2 [ 7 KB, 8 KB) ``` - after: ``` 242 [ 0 KB, 1 KB) 1 [ 6 KB, 7 KB) 2 [ 7 KB, 8 KB) ``` Reviewed By: pdillinger Differential Revision: D43388507 Pulled By: ajkr fbshipit-source-id: a02413c9f615b00784700646825a9870ee10f3a7 |
2 years ago |
Levi Tamasi | 9794acb597 |
Add a new MultiGetEntity API (#11222)
Summary: The new `MultiGetEntity` API can be used to get a consistent view of a batch of keys, with the results presented as wide-column entities. Similarly to `GetEntity` and the iterator's `columns` API, if the entry corresponding to the key is a wide-column entity to start with, it is returned as-is, and if it is a plain key-value, it is wrapped into an entity with a single default column. Implementation-wise, the new API shares the logic of the batched `MultiGet` API (via the `MultiGetCommon` methods). Both single-CF and multi-CF `MultiGetEntity` APIs are provided, and blobs are also supported. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11222 Test Plan: `make check` Reviewed By: akankshamahajan15 Differential Revision: D43256950 Pulled By: ltamasi fbshipit-source-id: 47fb2cb7e2d0470e3580f43fdb2fe9e51f0e7005 |
2 years ago |
Wentian Guo | 42d6652ba2 |
remove dependency on options.h for port_posix.h andport_win.h (#11214)
Summary: The files in `port/`, such as `port_posix.h`, are layering over the system libraries, so shouldn't include the DB-specific files like `options.h`. This PR remove this dependency. # How The reason that `port_posix.h` (or `port_win.h`) include `options.h` is to use `CpuPriority`, as there is a method `SetCpuPriority()` in `port_posix.h` that uses `CpuPriority.` - I think `SetCpuPriority()` make sense to exist in `port_posix.h` as it provides has platform-dependent implementation - `CpuPriority` enum is defined in `env.h`, but used in `rocksdb/include` and `port/`. Hence, let us define `CpuPriority` enum in a common file, say `port_defs.h`, such that both directories `rocksdb/include` and `port/` can include. When we remove this dependency, some other files have compile errors because they can't find definitions, so add header files to resolve # Test make all check -j Pull Request resolved: https://github.com/facebook/rocksdb/pull/11214 Reviewed By: pdillinger Differential Revision: D43196910 Pulled By: guowentian fbshipit-source-id: 70deccb72844cfb08fcc994f76c6ef6df5d55ab9 |
2 years ago |
Peter Dillinger | 3cacd4b4ec |
Put Cache and CacheWrapper in new public header (#11192)
Summary: The definition of the Cache class should not be needed by the vast majority of RocksDB users, so I think it is just distracting to include it in cache.h, which is primarily needed for configuring and creating caches. This change moves the class to a new header advanced_cache.h. It is just cut-and-paste except for modifying the class API comment. In general, operations on shared_ptr<Cache> should continue to work when only a forward declaration of Cache is available, as long as all the Cache instances provided are already shared_ptr. See https://stackoverflow.com/a/17650101/454544 Also, the most common way to customize a Cache is by wrapping an existing implementation, so it makes sense to provide CacheWrapper in the public API. This was a cut-and-paste job except removing the implementation of Name() so that derived classes must provide it. Intended follow-up: consolidate Release() into one function to reduce customization bugs / confusion Pull Request resolved: https://github.com/facebook/rocksdb/pull/11192 Test Plan: `make check` Reviewed By: anand1976 Differential Revision: D43055487 Pulled By: pdillinger fbshipit-source-id: 7b05492df35e0f30b581b4c24c579bc275b6d110 |
2 years ago |
Hui Xiao | 6650ca244e |
Remove a couple deprecated convenience.h APIs (#11120)
Summary: **Context/Summary:** As instructed by convenience.h comments, a few deprecated APIs are removed. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11120 Test Plan: - make check & CI - eyeball check on test semantics. Reviewed By: pdillinger Differential Revision: D42937507 Pulled By: hx235 fbshipit-source-id: a9e4709387da01b1d0e9148c2e210f02e9746ee1 |
2 years ago |
Yu Zhang | 24ac53d81a |
Use user key on sst file for blob verification for Get and MultiGet (#11105)
Summary: Use the user key on sst file for blob verification for `Get` and `MultiGet` instead of the user key passed from caller. Add tests for `Get` and `MultiGet` operations when user defined timestamp feature is enabled in a BlobDB. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11105 Test Plan: make V=1 db_blob_basic_test ./db_blob_basic_test --gtest_filter="DBBlobTestWithTimestamp.*" Reviewed By: ltamasi Differential Revision: D42716487 Pulled By: jowlyzhang fbshipit-source-id: 5987ecbb7e56ddf46d2467a3649369390789506a |
2 years ago |
sdong | 4720ba4391 |
Remove RocksDB LITE (#11147)
Summary: We haven't been actively mantaining RocksDB LITE recently and the size must have been gone up significantly. We are removing the support. Most of changes were done through following comments: unifdef -m -UROCKSDB_LITE `git grep -l ROCKSDB_LITE | egrep '[.](cc|h)'` by Peter Dillinger. Others changes were manually applied to build scripts, CircleCI manifests, ROCKSDB_LITE is used in an expression and file db_stress_test_base.cc. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11147 Test Plan: See CI Reviewed By: pdillinger Differential Revision: D42796341 fbshipit-source-id: 4920e15fc2060c2cd2221330a6d0e5e65d4b7fe2 |
2 years ago |
Karim TAAM | a1e92bd956 |
use verify checksum option in block based table reader Open() (#11099)
Summary: ## Description In this issue https://github.com/facebook/rocksdb/issues/11002 we found that when we use rocksdb with the `verify checksum` read_option to false the verification is done anyway By analyzing the code along the stacktrace I saw that at the level of https://github.com/facebook/rocksdb/compare/main...matkt:feature/use-verify-checksum-in-block-based-table-reader?expand=1#diff-57ed8c49db2bdd4db7618646a177397674bbf25beacacecb104070071d30129f we are not keeping all the options and we forget the `verify_checksum` the comment in this class suggests that it should be managed https://github.com/facebook/rocksdb/compare/main...matkt:feature/use-verify-checksum-in-block-based-table-reader?expand=1#diff-57ed8c49db2bdd4db7618646a177397674bbf25beacacecb104070071d30129fL581 <img width="1724" alt="204511641-86ab4b9b-45e5-4a2b-a13d-81fa26435d38" src="https://user-images.githubusercontent.com/26581503/213152802-c46bc1c7-a3a2-4a6f-9bb1-bf92ee93af7a.png"> this PR just adds the line to manage the `verify checksum` ## Tests - Running unit tests - Test without setting `verify checksum` and verifying that we are calling the checksum code - Test by setting `verify checksum` to true and verifying that we are calling the checksum code - Test by setting `verify checksum` to false and verifying that we are **not** calling the checksum code Pull Request resolved: https://github.com/facebook/rocksdb/pull/11099 Reviewed By: cbi42 Differential Revision: D42679881 Pulled By: ajkr fbshipit-source-id: c7dd10768282fd0699f7e1bf397ceb7adbea4ab6 |
2 years ago |
Heiko Becker | 88edfbfb5e |
Fix build with gcc 13 by including <cstdint> (#11118)
Summary: Like other versions before, gcc 13 moved some includes around and as a result <cstdint> is no longer transitively included [1]. Explicitly include it for uint{32,64}_t. [1] https://gcc.gnu.org/gcc-13/porting_to.html#header-dep-changes Pull Request resolved: https://github.com/facebook/rocksdb/pull/11118 Reviewed By: cbi42 Differential Revision: D42711356 Pulled By: ajkr fbshipit-source-id: 5ea257b85b7017f40fd8fdbce965336da95c55b2 |
2 years ago |
sdong | 2800aa069a |
Remove compressed block cache (#11117)
Summary: Compressed block cache is replaced by compressed secondary cache. Remove the feature. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11117 Test Plan: See CI passes Reviewed By: pdillinger Differential Revision: D42700164 fbshipit-source-id: 6cbb24e460da29311150865f60ecb98637f9f67d |
2 years ago |
Andrew Kryczka | b7fbcefda8 |
Add API to limit blast radius of merge operator failure (#11092)
Summary: Prior to this PR, `FullMergeV2()` can only return `false` to indicate failure, which causes any operation invoking it to fail. During a compaction, such a failure causes the compaction to fail and causes the DB to irreversibly enter read-only mode. Some users asked for a way to allow the merge operator to fail without such widespread damage. To limit the blast radius of merge operator failures, this PR introduces the `MergeOperationOutput::op_failure_scope` API. When unpopulated (`kDefault`) or set to `kTryMerge`, the merge operator failure handling is the same as before. When set to `kMustMerge`, merge operator failure still causes failure to operations that must merge (`Get()`, iterator, `MultiGet()`, etc.). However, under `kMustMerge`, flushes/compactions can survive merge operator failures by outputting the unmerged input operands. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11092 Reviewed By: siying Differential Revision: D42525673 Pulled By: ajkr fbshipit-source-id: 951dc3bf190f86347dccf3381be967565cda52ee |
2 years ago |
leipeng | a5bcbcd8be |
remove unused InternalIteratorBase::is_mutable_ (#11104)
Summary: `InternalIteratorBase::is_mutable_` is not used any more, remove it. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11104 Reviewed By: ajkr Differential Revision: D42582747 Pulled By: cbi42 fbshipit-source-id: d30bf75151fc8414df0ae112a6ec4943b5b7330b |
2 years ago |
Changyu Bi | f515d9d203 |
Revert #10802 Consider range tombstone in compaction output file cutting (#11089)
Summary:
This reverts commit
|
2 years ago |
Peter Dillinger | 9f7801c5f1 |
Major Cache refactoring, CPU efficiency improvement (#10975)
Summary: This is several refactorings bundled into one to avoid having to incrementally re-modify uses of Cache several times. Overall, there are breaking changes to Cache class, and it becomes more of low-level interface for implementing caches, especially block cache. New internal APIs make using Cache cleaner than before, and more insulated from block cache evolution. Hopefully, this is the last really big block cache refactoring, because of rather effectively decoupling the implementations from the uses. This change also removes the EXPERIMENTAL designation on the SecondaryCache support in Cache. It seems reasonably mature at this point but still subject to change/evolution (as I warn in the API docs for Cache). The high-level motivation for this refactoring is to minimize code duplication / compounding complexity in adding SecondaryCache support to HyperClockCache (in a later PR). Other benefits listed below. * static_cast lines of code +29 -35 (net removed 6) * reinterpret_cast lines of code +6 -32 (net removed 26) ## cache.h and secondary_cache.h * Always use CacheItemHelper with entries instead of just a Deleter. There are several motivations / justifications: * Simpler for implementations to deal with just one Insert and one Lookup. * Simpler and more efficient implementation because we don't have to track which entries are using helpers and which are using deleters * Gets rid of hack to classify cache entries by their deleter. Instead, the CacheItemHelper includes a CacheEntryRole. This simplifies a lot of code (cache_entry_roles.h almost eliminated). Fixes https://github.com/facebook/rocksdb/issues/9428. * Makes it trivial to adjust SecondaryCache behavior based on kind of block (e.g. don't re-compress filter blocks). * It is arguably less convenient for many direct users of Cache, but direct users of Cache are now rare with introduction of typed_cache.h (below). * I considered and rejected an alternative approach in which we reduce customizability by assuming each secondary cache compatible value starts with a Slice referencing the uncompressed block contents (already true or mostly true), but we apparently intend to stack secondary caches. Saving an entry from a compressed secondary to a lower tier requires custom handling offered by SaveToCallback, etc. * Make CreateCallback part of the helper and introduce CreateContext to work with it (alternative to https://github.com/facebook/rocksdb/issues/10562). This cleans up the interface while still allowing context to be provided for loading/parsing values into primary cache. This model works for async lookup in BlockBasedTable reader (reader owns a CreateContext) under the assumption that it always waits on secondary cache operations to finish. (Otherwise, the CreateContext could be destroyed while async operation depending on it continues.) This likely contributes most to the observed performance improvement because it saves an std::function backed by a heap allocation. * Use char* for serialized data, e.g. in SaveToCallback, where void* was confusingly used. (We use `char*` for serialized byte data all over RocksDB, with many advantages over `void*`. `memcpy` etc. are legacy APIs that should not be mimicked.) * Add a type alias Cache::ObjectPtr = void*, so that we can better indicate the intent of the void* when it is to be the object associated with a Cache entry. Related: started (but did not complete) a refactoring to move away from "value" of a cache entry toward "object" or "obj". (It is confusing to call Cache a key-value store (like DB) when it is really storing arbitrary in-memory objects, not byte strings.) * Remove unnecessary key param from DeleterFn. This is good for efficiency in HyperClockCache, which does not directly store the cache key in memory. (Alternative to https://github.com/facebook/rocksdb/issues/10774) * Add allocator to Cache DeleterFn. This is a kind of future-proofing change in case we get more serious about using the Cache allocator for memory tracked by the Cache. Right now, only the uncompressed block contents are allocated using the allocator, and a pointer to that allocator is saved as part of the cached object so that the deleter can use it. (See CacheAllocationPtr.) If in the future we are able to "flatten out" our Cache objects some more, it would be good not to have to track the allocator as part of each object. * Removes legacy `ApplyToAllCacheEntries` and changes `ApplyToAllEntries` signature for Deleter->CacheItemHelper change. ## typed_cache.h Adds various "typed" interfaces to the Cache as internal APIs, so that most uses of Cache can use simple type safe code without casting and without explicit deleters, etc. Almost all of the non-test, non-glue code uses of Cache have been migrated. (Follow-up work: CompressedSecondaryCache deserves deeper attention to migrate.) This change expands RocksDB's internal usage of metaprogramming and SFINAE (https://en.cppreference.com/w/cpp/language/sfinae). The existing usages of Cache are divided up at a high level into these new interfaces. See updated existing uses of Cache for examples of how these are used. * PlaceholderCacheInterface - Used for making cache reservations, with entries that have a charge but no value. * BasicTypedCacheInterface<TValue> - Used for primary cache storage of objects of type TValue, which can be cleaned up with std::default_delete<TValue>. The role is provided by TValue::kCacheEntryRole or given in an optional template parameter. * FullTypedCacheInterface<TValue, TCreateContext> - Used for secondary cache compatible storage of objects of type TValue. In addition to BasicTypedCacheInterface constraints, we require TValue::ContentSlice() to return persistable data. This simplifies usage for the normal case of simple secondary cache compatibility (can give you a Slice to the data already in memory). In addition to TCreateContext performing the role of Cache::CreateContext, it is also expected to provide a factory function for creating TValue. * For each of these, there's a "Shared" version (e.g. FullTypedSharedCacheInterface) that holds a shared_ptr to the Cache, rather than assuming external ownership by holding only a raw `Cache*`. These interfaces introduce specific handle types for each interface instantiation, so that it's easy to see what kind of object is controlled by a handle. (Ultimately, this might not be worth the extra complexity, but it seems OK so far.) Note: I attempted to make the cache 'charge' automatically inferred from the cache object type, such as by expecting an ApproximateMemoryUsage() function, but this is not so clean because there are cases where we need to compute the charge ahead of time and don't want to re-compute it. ## block_cache.h This header is essentially the replacement for the old block_like_traits.h. It includes various things to support block cache access with typed_cache.h for block-based table. ## block_based_table_reader.cc Before this change, accessing the block cache here was an awkward mix of static polymorphism (template TBlocklike) and switch-case on a dynamic BlockType value. This change mostly unifies on static polymorphism, relying on minor hacks in block_cache.h to distinguish variants of Block. We still check BlockType in some places (especially for stats, which could be improved in follow-up work) but at least the BlockType is a static constant from the template parameter. (No more awkward partial redundancy between static and dynamic info.) This likely contributes to the overall performance improvement, but hasn't been tested in isolation. The other key source of simplification here is a more unified system of creating block cache objects: for directly populating from primary cache and for promotion from secondary cache. Both use BlockCreateContext, for context and for factory functions. ## block_based_table_builder.cc, cache_dump_load_impl.cc Before this change, warming caches was super ugly code. Both of these source files had switch statements to basically transition from the dynamic BlockType world to the static TBlocklike world. None of that mess is needed anymore as there's a new, untyped WarmInCache function that handles all the details just as promotion from SecondaryCache would. (Fixes `TODO akanksha: Dedup below code` in block_based_table_builder.cc.) ## Everything else Mostly just updating Cache users to use new typed APIs when reasonably possible, or changed Cache APIs when not. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10975 Test Plan: tests updated Performance test setup similar to https://github.com/facebook/rocksdb/issues/10626 (by cache size, LRUCache when not "hyper" for HyperClockCache): 34MB 1thread base.hyper -> kops/s: 0.745 io_bytes/op: 2.52504e+06 miss_ratio: 0.140906 max_rss_mb: 76.4844 34MB 1thread new.hyper -> kops/s: 0.751 io_bytes/op: 2.5123e+06 miss_ratio: 0.140161 max_rss_mb: 79.3594 34MB 1thread base -> kops/s: 0.254 io_bytes/op: 1.36073e+07 miss_ratio: 0.918818 max_rss_mb: 45.9297 34MB 1thread new -> kops/s: 0.252 io_bytes/op: 1.36157e+07 miss_ratio: 0.918999 max_rss_mb: 44.1523 34MB 32thread base.hyper -> kops/s: 7.272 io_bytes/op: 2.88323e+06 miss_ratio: 0.162532 max_rss_mb: 516.602 34MB 32thread new.hyper -> kops/s: 7.214 io_bytes/op: 2.99046e+06 miss_ratio: 0.168818 max_rss_mb: 518.293 34MB 32thread base -> kops/s: 3.528 io_bytes/op: 1.35722e+07 miss_ratio: 0.914691 max_rss_mb: 264.926 34MB 32thread new -> kops/s: 3.604 io_bytes/op: 1.35744e+07 miss_ratio: 0.915054 max_rss_mb: 264.488 233MB 1thread base.hyper -> kops/s: 53.909 io_bytes/op: 2552.35 miss_ratio: 0.0440566 max_rss_mb: 241.984 233MB 1thread new.hyper -> kops/s: 62.792 io_bytes/op: 2549.79 miss_ratio: 0.044043 max_rss_mb: 241.922 233MB 1thread base -> kops/s: 1.197 io_bytes/op: 2.75173e+06 miss_ratio: 0.103093 max_rss_mb: 241.559 233MB 1thread new -> kops/s: 1.199 io_bytes/op: 2.73723e+06 miss_ratio: 0.10305 max_rss_mb: 240.93 233MB 32thread base.hyper -> kops/s: 1298.69 io_bytes/op: 2539.12 miss_ratio: 0.0440307 max_rss_mb: 371.418 233MB 32thread new.hyper -> kops/s: 1421.35 io_bytes/op: 2538.75 miss_ratio: 0.0440307 max_rss_mb: 347.273 233MB 32thread base -> kops/s: 9.693 io_bytes/op: 2.77304e+06 miss_ratio: 0.103745 max_rss_mb: 569.691 233MB 32thread new -> kops/s: 9.75 io_bytes/op: 2.77559e+06 miss_ratio: 0.103798 max_rss_mb: 552.82 1597MB 1thread base.hyper -> kops/s: 58.607 io_bytes/op: 1449.14 miss_ratio: 0.0249324 max_rss_mb: 1583.55 1597MB 1thread new.hyper -> kops/s: 69.6 io_bytes/op: 1434.89 miss_ratio: 0.0247167 max_rss_mb: 1584.02 1597MB 1thread base -> kops/s: 60.478 io_bytes/op: 1421.28 miss_ratio: 0.024452 max_rss_mb: 1589.45 1597MB 1thread new -> kops/s: 63.973 io_bytes/op: 1416.07 miss_ratio: 0.0243766 max_rss_mb: 1589.24 1597MB 32thread base.hyper -> kops/s: 1436.2 io_bytes/op: 1357.93 miss_ratio: 0.0235353 max_rss_mb: 1692.92 1597MB 32thread new.hyper -> kops/s: 1605.03 io_bytes/op: 1358.04 miss_ratio: 0.023538 max_rss_mb: 1702.78 1597MB 32thread base -> kops/s: 280.059 io_bytes/op: 1350.34 miss_ratio: 0.023289 max_rss_mb: 1675.36 1597MB 32thread new -> kops/s: 283.125 io_bytes/op: 1351.05 miss_ratio: 0.0232797 max_rss_mb: 1703.83 Almost uniformly improving over base revision, especially for hot paths with HyperClockCache, up to 12% higher throughput seen (1597MB, 32thread, hyper). The improvement for that is likely coming from much simplified code for providing context for secondary cache promotion (CreateCallback/CreateContext), and possibly from less branching in block_based_table_reader. And likely a small improvement from not reconstituting key for DeleterFn. Reviewed By: anand1976 Differential Revision: D42417818 Pulled By: pdillinger fbshipit-source-id: f86bfdd584dce27c028b151ba56818ad14f7a432 |
2 years ago |
anand76 | bec4264813 |
Avoid mixing sync and async prefetch (#11050)
Summary: Reading uncompression dict block always uses sync reads, while data blocks may use async reads and prefetching. This causes problems in FilePrefetchBuffer. So avoid mixing the two by reading the uncompression dict straight from the file. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11050 Test Plan: Crash test Reviewed By: akankshamahajan15 Differential Revision: D42194682 Pulled By: anand1976 fbshipit-source-id: aaa8b396fdfe966b157e210f5ef8501c45b7b69e |
2 years ago |
Changyu Bi | f02c708aa3 |
Consider range tombstone in compaction output file cutting (#10802)
Summary: This PR is the first step for Issue https://github.com/facebook/rocksdb/issues/4811. Currently compaction output files are cut at point keys, and the decision is made mainly in `CompactionOutputs::ShouldStopBefore()`. This makes it possible for range tombstones to cause large compactions that does not respect `max_compaction_bytes`. For example, we can have a large range tombstone that overlaps with too many files from the next level. Another example is when there is a gap between a range tombstone and another key. The first issue may be more acceptable, as a lot of data is deleted. This PR address the second issue by calling `ShouldStopBefore()` for range tombstone start keys. The main change is for `CompactionIterator` to emit range tombstone start keys to be processed by `CompactionOutputs`. A new `CompactionMergingIterator` is introduced and only used under `CompactionIterator` for this purpose. Further improvement after this PR include 1) cut compaction output at some grandparent boundary key instead of at the next point key or range tombstone start key and 2) cut compaction output file within a large range tombstone (it may be easier and reasonable to only do it for range tombstones at the end of a compaction output). Pull Request resolved: https://github.com/facebook/rocksdb/pull/10802 Test Plan: - added unit tests in db_range_del_test. - stress test: `python3 tools/db_crashtest.py whitebox --[simple|enable_ts] --verify_iterator_with_expected_state_one_in=5 --delrangepercent=5 --prefixpercent=2 --writepercent=58 --readpercen=21 --duration=36000 --range_deletion_width=1000000` Reviewed By: ajkr, jay-zhuang Differential Revision: D40308827 Pulled By: cbi42 fbshipit-source-id: a8fd6f70a3f09d0ef7a40e006f6c964bba8c00df |
2 years ago |
Arvid Lunnemark | 00238a386b |
replace sprintf with its safe version snprintf (v2) (#11011)
Summary: same motivations as https://github.com/facebook/rocksdb/pull/5475, applied to the last remaining `sprintf`. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11011 Reviewed By: pdillinger Differential Revision: D41673500 Pulled By: ajkr fbshipit-source-id: 88618ea791cafad86a9a491799c45979d46e3544 |
2 years ago |
Peter Dillinger | 433d7e4594 |
Improve error messages for SST footer and size errors (#11009)
Summary: Previously, you could get a format_version error if SST file size was too small in manifest, or a weird "too short" error if too big in manifest. Now we ensure: * Magic number error is reported first if we attempt to open an SST file and the footer is completely bad. * Footer errors are reported with affected file. * If manifest file size doesn't match actual, then the error includes expected and actual sizes (if an error is reported; in some cases we allow the file to be too big) Pull Request resolved: https://github.com/facebook/rocksdb/pull/11009 Test Plan: unit tests added, some manual Previously, the code for "file too short" in footer processing was only covered by some tests attempting to verify SST checksums on non-SST files (fixed). Reviewed By: siying Differential Revision: D41656272 Pulled By: pdillinger fbshipit-source-id: 3da32702eb5aaedbea0e5e74742ad57edd7ad3df |
2 years ago |
Changyu Bi | 6cdb7af9f8 |
Remove copying of range tombstones keys in iterator (#10878)
Summary: In MergingIterator, if a range tombstone's start or end key is added to minHeap/maxHeap, the key is copied. This PR removes the copying of range tombstone keys by adding InternalKey comparator that compares `Slice` for internal key and `ParsedInternalKey` directly. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10878 Test Plan: - existing UT - ran all flavors of stress test through sandcastle - benchmarks: I did not get improvement when compiling with DEBUG_LEVEL=0, and saw many noise. With `OPTIMIZE_LEVEL="-O3" USE_LTO=1` I do see improvement. ``` # Favorable set up: half of the writes are DeleteRange. TEST_TMPDIR=/tmp/rocksdb-rangedel-test-all-tombstone ./db_bench --benchmarks=fillseq,levelstats --writes_per_range_tombstone=1 --max_num_range_tombstones=1000000 --range_tombstone_width=2 --num=1000000 --max_bytes_for_level_base=4194304 --disable_auto_compactions --write_buffer_size=33554432 --key_size=50 # benchmark command TEST_TMPDIR=/tmp/rocksdb-rangedel-test-all-tombstone ./db_bench --benchmarks=readseq[-W1][-X5],levelstats --use_existing_db=true --cache_size=3221225472 --disable_auto_compactions=true --avoid_flush_during_recovery=true --seek_nexts=100 --reads=1000000 --num=1000000 --threads=25 # main readseq [AVG 5 runs] : 26017977 (± 371077) ops/sec; 3721.9 (± 53.1) MB/sec readseq [MEDIAN 5 runs] : 26096905 ops/sec; 3733.2 MB/sec # this PR readseq [AVG 5 runs] : 27481724 (± 568758) ops/sec; 3931.3 (± 81.4) MB/sec readseq [MEDIAN 5 runs] : 27323957 ops/sec; 3908.7 MB/sec ``` Reviewed By: ajkr Differential Revision: D40711170 Pulled By: cbi42 fbshipit-source-id: 708cb584e2bd085a9ce0d2ef6a420489f721717f |
2 years ago |
Changyu Bi | 534fb06dd3 |
Prevent iterating over range tombstones beyond `iterate_upper_bound` (#10966)
Summary: Currently, `iterate_upper_bound` is not checked for range tombstone keys in MergingIterator. This may impact performance when there is a large number of range tombstones right after `iterate_upper_bound`. This PR fixes this issue by checking `iterate_upper_bound` in MergingIterator for range tombstone keys. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10966 Test Plan: - added unit test - stress test: `python3 tools/db_crashtest.py whitebox --simple --verify_iterator_with_expected_state_one_in=5 --delrangepercent=5 --prefixpercent=18 --writepercent=48 --readpercen=15 --duration=36000 --range_deletion_width=100` - ran different stress tests over sandcastle - Falcon team ran some test traffic and saw reduced CPU usage on processing range tombstones. Reviewed By: ajkr Differential Revision: D41414172 Pulled By: cbi42 fbshipit-source-id: 9b2c29eb3abb99327c6a649bdc412e70d863f981 |
2 years ago |
Peter Dillinger | f321e8fc98 |
Don't attempt to use SecondaryCache on block_cache_compressed (#10944)
Summary: Compressed block cache depends on reading the block compression marker beyond the payload block size. Only the payload bytes were being saved and loaded from SecondaryCache -> boom! This removes some unnecessary code attempting to combine these two competing features. Note that BlockContents was previously used for block-based filter in block cache, but that support has been removed. Also marking block_cache_compressed as deprecated in this commit as we expect it to be replaced with SecondaryCache. This problem was discovered during refactoring but didn't want to combine bug fix with that refactoring. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10944 Test Plan: test added that fails on base revision (at least with ASAN) Reviewed By: akankshamahajan15 Differential Revision: D41205578 Pulled By: pdillinger fbshipit-source-id: 1b29d36c7a6552355ac6511fcdc67038ef4af29f |
2 years ago |
Levi Tamasi | 2ea109521f |
Revisit the interface of MergeHelper::TimedFullMerge(WithEntity) (#10932)
Summary: The patch refines/reworks `MergeHelper::TimedFullMerge(WithEntity)` a bit in two ways. First, it eliminates the recently introduced `TimedFullMerge` overload, which makes the responsibilities clearer by making sure the query result (`value` for `Get`, `columns` for `GetEntity`) is set uniformly in `SaveValue` and `GetContext`. Second, it changes the interface of `TimedFullMergeWithEntity` so it exposes its result in a serialized form; this is a more decoupled design which will come in handy when adding support for `Merge` with wide-column entities to `DBIter`. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10932 Test Plan: `make check` Reviewed By: akankshamahajan15 Differential Revision: D41129399 Pulled By: ltamasi fbshipit-source-id: 69d8da358c77d4fc7e8c40f4dafc2c129a710677 |
2 years ago |
Levi Tamasi | fbd9077d66 |
Fix a bug where GetContext does not update READ_NUM_MERGE_OPERANDS (#10925)
Summary: The patch fixes a bug where `GetContext::Merge` (and `MergeEntity`) does not update the ticker `READ_NUM_MERGE_OPERANDS` because it implicitly uses the default parameter value of `update_num_ops_stats=false` when calling `MergeHelper::TimedFullMerge`. Also, to prevent such issues going forward, the PR removes the default parameter values from the `TimedFullMerge` methods. In addition, it removes an unused/unnecessary parameter from `TimedFullMergeWithEntity`, and does some cleanup at the call sites of these methods. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10925 Test Plan: `make check` Reviewed By: riversand963 Differential Revision: D41096453 Pulled By: ltamasi fbshipit-source-id: fc60646d32b4d516b8fe81e265c3f020a32fd7f8 |
2 years ago |
Levi Tamasi | 941d834739 |
Support Merge for wide-column entities during point lookups (#10916)
Summary: The patch adds `Merge` support for wide-column entities to the point lookup APIs, i.e. `Get`, `MultiGet`, `GetEntity`, and `GetMergeOperands`. (I plan to update the iterator and compaction logic in separate PRs.) In terms of semantics, the `Merge` operation is applied to the default (anonymous) column; any other columns in the entity are unaffected. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10916 Test Plan: `make check` Reviewed By: riversand963 Differential Revision: D40962311 Pulled By: ltamasi fbshipit-source-id: 244bc9d172be1af2f204796b2f89104e4d2fa373 |
2 years ago |
Yanqin Jin | 7d26e4c5a3 |
Basic Support for Merge with user-defined timestamp (#10819)
Summary: This PR implements the originally disabled `Merge()` APIs when user-defined timestamp is enabled. Simplest usage: ```cpp // assume string append merge op is used with '.' as delimiter. // ts1 < ts2 db->Put(WriteOptions(), "key", ts1, "v0"); db->Merge(WriteOptions(), "key", ts2, "1"); ReadOptions ro; ro.timestamp = &ts2; db->Get(ro, "key", &value); ASSERT_EQ("v0.1", value); ``` Some code comments are added for clarity. Note: support for timestamp in `DB::GetMergeOperands()` will be done in a follow-up PR. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10819 Test Plan: make check Reviewed By: ltamasi Differential Revision: D40603195 Pulled By: riversand963 fbshipit-source-id: f96d6f183258f3392d80377025529f7660503013 |
2 years ago |
Yanqin Jin | 9079895aae |
Fix deletion counting in memtable stats (#10886)
Summary: Currently, a memtable's stats `num_deletes_` is incremented only if the entry is a regular delete (kTypeDeletion). We need to fix it by accounting for kTypeSingleDeletion and kTypeDeletionWithTimestamp. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10886 Test Plan: make check Reviewed By: ltamasi Differential Revision: D40740754 Pulled By: riversand963 fbshipit-source-id: 7bde62cd6df136585bc5bfb1c426c7a8276c08e1 |
2 years ago |
Jay Zhuang | 36f5e19e33 |
Fix a Windows build error (#10897)
Summary: The for loop is marked as unreachable code because it will never call the increment. Switch it to `if`. ``` \table\merging_iterator.cc(823): error C2220: the following warning is treated as an error \table\merging_iterator.cc(823): warning C4702: unreachable code \table\merging_iterator.cc(1030): error C2220: the following warning is treated as an error \table\merging_iterator.cc(1030): warning C4702: unreachable code ``` Pull Request resolved: https://github.com/facebook/rocksdb/pull/10897 Reviewed By: cbi42 Differential Revision: D40811790 Pulled By: jay-zhuang fbshipit-source-id: fe8fd3e7cf3d6f710360c402b79763854d5120df |
2 years ago |
Levi Tamasi | 7867a1112b |
Handle Merges correctly in GetEntity (#10894)
Summary: The PR fixes the handling of `Merge`s in `GetEntity`. Note that `Merge` is not yet supported for wide-column entities written using `PutEntity`; this change is about returning correct (i.e. consistent with `Get`) results in cases like when the base value is a plain old key-value written using `Put` or when there is no real base value because we hit either a tombstone or the beginning of history. Implementation-wise, the patch introduces a new wrapper around the existing `MergeHelper::TimedFullMerge` that can store the merge result in either a string (for the purposes of `Get`) or a `PinnableWideColumns` instance (for `GetEntity`). Pull Request resolved: https://github.com/facebook/rocksdb/pull/10894 Test Plan: `make check` Reviewed By: riversand963 Differential Revision: D40782708 Pulled By: ltamasi fbshipit-source-id: 3d700d56b2ef81f02ba1e2d93f6481bf13abcc90 |
2 years ago |
Changyu Bi | 56715350d9 |
Reduce heap operations for range tombstone keys in iterator (#10877)
Summary: Right now in MergingIterator, for each range tombstone start and end key, we pop one end from heap and push the other end into the heap. This involves extra downheap and upheap cost. In the likely cases when a range tombstone iterator emits relatively adjacent keys, these keys should have similar order within all keys in the heap. This can happen when there is a burst of consecutive range tombstones, and most of the keys covered by them are dropped already. This PR uses `replace_top()` when inserting new range tombstone keys, which is more efficient in these common cases. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10877 Test Plan: - existing UT - ran all flavors of stress test through sandcastle - benchmark: ``` # Set up: --writes_per_range_tombstone=1 means one point write and one delete range TEST_TMPDIR=/tmp/rocksdb-rangedel-test-all-tombstone ./db_bench --benchmarks=fillseq,levelstats --writes_per_range_tombstone=1 --max_num_range_tombstones=1000000 --range_tombstone_width=2 --num=100000000 --writes=800000 --max_bytes_for_level_base=4194304 --disable_auto_compactions --write_buffer_size=33554432 --key_size=64 Level Files Size(MB) -------------------- 0 8 152 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 # Benchmark TEST_TMPDIR=/tmp/rocksdb-rangedel-test-all-tombstone/ ./db_bench --benchmarks=readseq[-W1][-X5],levelstats --use_existing_db=true --cache_size=3221225472 --num=100000000 --reads=1000000 --disable_auto_compactions=true --avoid_flush_during_recovery=true # Pre PR readseq [AVG 5 runs] : 1432116 (± 59664) ops/sec; 224.0 (± 9.3) MB/sec readseq [MEDIAN 5 runs] : 1454886 ops/sec; 227.5 MB/sec # Post PR readseq [AVG 5 runs] : 1944425 (± 29521) ops/sec; 304.1 (± 4.6) MB/sec readseq [MEDIAN 5 runs] : 1959430 ops/sec; 306.5 MB/sec ``` Reviewed By: ajkr Differential Revision: D40710936 Pulled By: cbi42 fbshipit-source-id: cb782fb9cdcd26c0c3eb9443215a4ef4d2f79022 |
2 years ago |
sdong | 3e686c7cbe |
sst_dump --command=raw to add index offset information (#10873)
Summary: Add some extra information in outputs of "sst_dump --command=raw" to help debug some issues. Right now, encoded block handle is printed out. It is more useful to directly print out offset and size. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10873 Test Plan: Manually run it against a file and check the output. Reviewed By: anand1976 Differential Revision: D40742289 fbshipit-source-id: 04d7de26e7f27e1595a7cc3ac1c1082e4e835b93 |
2 years ago |
anand76 | 727bad78b8 |
Format files under table/ by clang-format (#10852)
Summary: Run clang-format on files under the `table` directory. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10852 Reviewed By: ajkr Differential Revision: D40650732 Pulled By: anand1976 fbshipit-source-id: 2023a958e37fd6274040c5181130284600c9e0ef |
2 years ago |
Changyu Bi | 7a95938899 |
Improve FragmentTombstones() speed by lazily initializing `seq_set_` (#10848)
Summary: FragmentedRangeTombstoneList has a member variable `seq_set_` that contains the sequence numbers of all range tombstones in a set. The set is constructed in `FragmentTombstones()` and is used only in `FragmentedRangeTombstoneList::ContainsRange()` which only happens during compaction. This PR moves the initialization of `seq_set_` to `FragmentedRangeTombstoneList::ContainsRange()`. This should speed up `FragmentTombstones()` when the range tombstone list is used for read/scan requests. Microbench shows the speed improvement to be ~45%. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10848 Test Plan: - Existing tests and stress test: `python3 tools/db_crashtest.py whitebox --simple --verify_iterator_with_expected_state_one_in=5`. - Microbench: update `range_del_aggregator_bench` to benchmark speed of `FragmentTombstones()`: ``` ./range_del_aggregator_bench --num_range_tombstones=1000 --tombstone_start_upper_bound=50000000 --num_runs=10000 --tombstone_width_mean=200 --should_deletes_per_run=100 --use_compaction_range_del_aggregator=true Before this PR: ========================= Fragment Tombstones: 270.286 us AddTombstones: 1.28933 us ShouldDelete (first): 0.525528 us ShouldDelete (rest): 0.0797519 us After this PR: time to fragment tombstones is pushed to AddTombstones() which only happen during compaction. ========================= Fragment Tombstones: 149.879 us AddTombstones: 102.131 us ShouldDelete (first): 0.565871 us ShouldDelete (rest): 0.0729444 us ``` - db_bench: this should improve speed for fragmenting range tombstones for mutable memtable: ``` ./db_bench --benchmarks=readwhilewriting --writes_per_range_tombstone=100 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=500000 --reads=250000 --disable_auto_compactions --max_num_range_tombstones=100000 --finish_after_writes --write_buffer_size=1073741824 --threads=25 Before this PR: readwhilewriting : 18.301 micros/op 1310445 ops/sec 4.769 seconds 6250000 operations; 28.1 MB/s (41001 of 250000 found) After this PR: readwhilewriting : 16.943 micros/op 1439376 ops/sec 4.342 seconds 6250000 operations; 23.8 MB/s (28977 of 250000 found) ``` Reviewed By: ajkr Differential Revision: D40646227 Pulled By: cbi42 fbshipit-source-id: ea471667edb258f67d01cfd828588e80a89e4083 |
2 years ago |
Changyu Bi | deb6a24be2 |
Remove range tombstone test code from sst_file_reader (#10847)
Summary: `#include "db/range_tombstone_fragmenter.h"` seems to break some internal test for 7.8 release. I'm removing it from sst_file_reader.h for now to unblock release. This should be fine as it is only used in a unit test for DeleteRange with timestamp. In addition, it does not seem to be useful to support delete range for sst file writer, since the range tombstone won't cover any key (its sequence number is 0). So maybe we can remove it in the future. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10847 Test Plan: CI. Reviewed By: akankshamahajan15 Differential Revision: D40620865 Pulled By: cbi42 fbshipit-source-id: be44b2f31e062bff87ed1b8d94482c3f7eaa370c |
2 years ago |
Peter Dillinger | 27c9705ac4 |
Use kXXH3 as default checksum (CPU efficiency) (#10778)
Summary: Since this has been supported for about a year, I think it's time to make it the default. This should improve CPU efficiency slightly on most hardware. A current DB performance comparison using buck+clang build: ``` TEST_TMPDIR=/dev/shm ./db_bench -checksum_type={1,4} -benchmarks=fillseq[-X1000] -num=3000000 -disable_wal ``` kXXH3 (+0.2% DB write throughput): `fillseq [AVG 1000 runs] : 822149 (± 1004) ops/sec; 91.0 (± 0.1) MB/sec` kCRC32c: `fillseq [AVG 1000 runs] : 820484 (± 1203) ops/sec; 90.8 (± 0.1) MB/sec` Micro benchmark comparison: ``` ./db_bench --benchmarks=xxh3[-X20],crc32c[-X20] ``` Machine 1, buck+clang build: `xxh3 [AVG 20 runs] : 3358616 (± 19091) ops/sec; 13119.6 (± 74.6) MB/sec` `crc32c [AVG 20 runs] : 2578725 (± 7742) ops/sec; 10073.1 (± 30.2) MB/sec` Machine 2, make+gcc build, DEBUG_LEVEL=0 PORTABLE=0: `xxh3 [AVG 20 runs] : 6182084 (± 137223) ops/sec; 24148.8 (± 536.0) MB/sec` `crc32c [AVG 20 runs] : 5032465 (± 42454) ops/sec; 19658.1 (± 165.8) MB/sec` Pull Request resolved: https://github.com/facebook/rocksdb/pull/10778 Test Plan: make check, unit tests updated Reviewed By: ajkr Differential Revision: D40112510 Pulled By: pdillinger fbshipit-source-id: e59a8d50a60346137732f8668ba7cfac93be2b37 |
2 years ago |
akankshamahajan | 0e7b27bfcf |
Refactor block cache tracing APIs (#10811)
Summary: Refactor the classes, APIs and data structures for block cache tracing to allow a user provided trace writer to be used. Currently, only a TraceWriter is supported, with a default built-in implementation of FileTraceWriter. The TraceWriter, however, takes a flat trace record and is thus only suitable for file tracing. This PR introduces an abstract BlockCacheTraceWriter class that takes a structured BlockCacheTraceRecord. The BlockCacheTraceWriter implementation can then format and log the record in whatever way it sees fit. The default BlockCacheTraceWriterImpl does file tracing using a user provided TraceWriter. `DB::StartBlockTrace` will internally redirect to changed `BlockCacheTrace::StartBlockCacheTrace`. New API `DB::StartBlockTrace` is also added that directly takes `BlockCacheTraceWriter` pointer. This same philosophy can be applied to KV and IO tracing as well. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10811 Test Plan: existing unit tests Old API DB::StartBlockTrace checked with db_bench tool create database ``` ./db_bench --benchmarks="fillseq" \ --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 \ --cache_index_and_filter_blocks --cache_size=1048576 \ --disable_auto_compactions=1 --disable_wal=1 --compression_type=none \ --min_level_to_compress=-1 --compression_ratio=1 --num=10000000 ``` To trace block cache accesses when running readrandom benchmark: ``` ./db_bench --benchmarks="readrandom" --use_existing_db --duration=60 \ --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 \ --cache_index_and_filter_blocks --cache_size=1048576 \ --disable_auto_compactions=1 --disable_wal=1 --compression_type=none \ --min_level_to_compress=-1 --compression_ratio=1 --num=10000000 \ --threads=16 \ -block_cache_trace_file="/tmp/binary_trace_test_example" \ -block_cache_trace_max_trace_file_size_in_bytes=1073741824 \ -block_cache_trace_sampling_frequency=1 ``` Reviewed By: anand1976 Differential Revision: D40435289 Pulled By: akankshamahajan15 fbshipit-source-id: fa2755f4788185e19f4605e731641cfd21ab3282 |
2 years ago |
Peter Dillinger | 7555243bcf |
Refactor ShardedCache for more sharing, static polymorphism (#10801)
Summary: The motivations for this change include * Free up space in ClockHandle so that we can add data for secondary cache handling while still keeping within single cache line (64 byte) size. * This change frees up space by eliminating the need for the `hash` field by making the fixed-size key itself a hash, using a 128-bit bijective (lossless) hash. * Generally more customizability of ShardedCache (such as hashing) without worrying about virtual call overheads * ShardedCache now uses static polymorphism (template) instead of dynamic polymorphism (virtual overrides) for the CacheShard. No obvious performance benefit is seen from the change (as mostly expected; most calls to virtual functions in CacheShard could already be optimized to static calls), but offers more flexibility without incurring the runtime cost of adhering to a common interface (without type parameters or static callbacks). * You'll also notice less `reinterpret_cast`ing and other boilerplate in the Cache implementations, as this can go in ShardedCache. More detail: * Don't have LRUCacheShard maintain `std::shared_ptr<SecondaryCache>` copies (extra refcount) when LRUCache can be in charge of keeping a `shared_ptr`. * Renamed `capacity_mutex_` to `config_mutex_` to better represent the scope of what it guards. * Some preparation for 64-bit hash and indexing in LRUCache, but didn't include the full change because of slight performance regression. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10801 Test Plan: Unit test updates were non-trivial because of major changes to the ClockCacheShard interface in handling of key vs. hash. Performance: Create with `TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=30000000 -disable_wal=1 -bloom_bits=16` Test with ``` TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=readrandom[-X1000] -readonly -num=30000000 -bloom_bits=16 -cache_index_and_filter_blocks=1 -cache_size=610000000 -duration 20 -threads=16 ``` Before: `readrandom [AVG 150 runs] : 321147 (± 253) ops/sec` After: `readrandom [AVG 150 runs] : 321530 (± 326) ops/sec` So possibly ~0.1% improvement. And with `-cache_type=hyper_clock_cache`: Before: `readrandom [AVG 30 runs] : 614126 (± 7978) ops/sec` After: `readrandom [AVG 30 runs] : 645349 (± 8087) ops/sec` So roughly 5% improvement! Reviewed By: anand1976 Differential Revision: D40252236 Pulled By: pdillinger fbshipit-source-id: ff8fc70ef569585edc95bcbaaa0386f61355ae5b |
2 years ago |
Peter Dillinger | e466173d5c |
Print stack traces on frozen tests in CI (#10828)
Summary: Instead of existing calls to ps from gnu_parallel, call a new wrapper that does ps, looks for unit test like processes, and uses pstack or gdb to print thread stack traces. Also, using `ps -wwf` instead of `ps -wf` ensures output is not cut off. For security, CircleCI runs with security restrictions on ptrace (/proc/sys/kernel/yama/ptrace_scope = 1), and this change adds a work-around to `InstallStackTraceHandler()` (only used by testing tools) to allow any process from the same user to debug it. (I've also touched >100 files to ensure all the unit tests call this function.) Pull Request resolved: https://github.com/facebook/rocksdb/pull/10828 Test Plan: local manual + temporary infinite loop in a unit test to observe in CircleCI Reviewed By: hx235 Differential Revision: D40447634 Pulled By: pdillinger fbshipit-source-id: 718a4c4a5b54fa0f9af2d01a446162b45e5e84e1 |
2 years ago |
Changyu Bi | 9f2363f4c4 |
User-defined timestamp support for `DeleteRange()` (#10661)
Summary: Add user-defined timestamp support for range deletion. The new API is `DeleteRange(opt, cf, begin_key, end_key, ts)`. Most of the change is to update the comparator to compare without timestamp. Other than that, major changes are - internal range tombstone data structures (`FragmentedRangeTombstoneList`, `RangeTombstone`, etc.) to store timestamps. - Garbage collection of range tombstones and range tombstone covered keys during compaction. - Get()/MultiGet() to return the timestamp of a range tombstone when needed. - Get/Iterator with range tombstones bounded by readoptions.timestamp. - timestamp crash test now issues DeleteRange by default. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10661 Test Plan: - Added unit test: `make check` - Stress test: `python3 tools/db_crashtest.py --enable_ts whitebox --readpercent=57 --prefixpercent=4 --writepercent=25 -delpercent=5 --iterpercent=5 --delrangepercent=4` - Ran `db_bench` to measure regression when timestamp is not enabled. The tests are for write (with some range deletion) and iterate with DB fitting in memory: `./db_bench--benchmarks=fillrandom,seekrandom --writes_per_range_tombstone=200 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=500000 --reads=500000 --seek_nexts=10 --disable_auto_compactions -disable_wal=true --max_num_range_tombstones=1000`. Did not see consistent regression in no timestamp case. | micros/op | fillrandom | seekrandom | | --- | --- | --- | |main| 2.58 |10.96| |PR 10661| 2.68 |10.63| Reviewed By: riversand963 Differential Revision: D39441192 Pulled By: cbi42 fbshipit-source-id: f05aca3c41605caf110daf0ff405919f300ddec2 |
2 years ago |
Jay Zhuang | f3cc66632b |
Align compaction output file boundaries to the next level ones (#10655)
Summary: Try to align the compaction output file boundaries to the next level ones (grandparent level), to reduce the level compaction write-amplification. In level compaction, there are "wasted" data at the beginning and end of the output level files. Align the file boundary can avoid such "wasted" compaction. With this PR, it tries to align the non-bottommost level file boundaries to its next level ones. It may cut file when the file size is large enough (at least 50% of target_file_size) and not too large (2x target_file_size). db_bench shows about 12.56% compaction reduction: ``` TEST_TMPDIR=/data/dbbench2 ./db_bench --benchmarks=fillrandom,readrandom -max_background_jobs=12 -num=400000000 -target_file_size_base=33554432 # baseline: Flush(GB): cumulative 25.882, interval 7.216 Cumulative compaction: 285.90 GB write, 162.36 MB/s write, 269.68 GB read, 153.15 MB/s read, 2926.7 seconds # with this change: Flush(GB): cumulative 25.882, interval 7.753 Cumulative compaction: 249.97 GB write, 141.96 MB/s write, 233.74 GB read, 132.74 MB/s read, 2534.9 seconds ``` The compaction simulator shows a similar result (14% with 100G random data). As a side effect, with this PR, the SST file size can exceed the target_file_size, but is capped at 2x target_file_size. And there will be smaller files. Here are file size statistics when loading 100GB with the target file size 32MB: ``` baseline this_PR count 1.656000e+03 1.705000e+03 mean 3.116062e+07 3.028076e+07 std 7.145242e+06 8.046139e+06 ``` The feature is enabled by default, to revert to the old behavior disable it with `AdvancedColumnFamilyOptions.level_compaction_dynamic_file_size = false` Also includes https://github.com/facebook/rocksdb/issues/1963 to cut file before skippable grandparent file. Which is for use case like user adding 2 or more non-overlapping data range at the same time, it can reduce the overlapping of 2 datasets in the lower levels. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10655 Reviewed By: cbi42 Differential Revision: D39552321 Pulled By: jay-zhuang fbshipit-source-id: 640d15f159ab0cd973f2426cfc3af266fc8bdde2 |
2 years ago |