Commit Graph

11669 Commits

Author SHA1 Message Date
Anatol Pomozov 4a83b16ce3 Use grep instead of obsolete egrep (#10701)
Summary:
It fixes "egrep: warning: egrep is obsolescent; using grep -E" warning at the systems with newer gnu grep.

https://www.phoronix.com/news/GNU-Grep-3.8-Stop-egrep-fgrep

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10701

Reviewed By: ajkr

Differential Revision: D39737908

Pulled By: cbi42

fbshipit-source-id: 13f3ccfc1a37d18541d156a6b4c2ba24f6c66589
2022-09-22 16:58:21 -07:00
dependabot[bot] 80d010a5e7 Bump commonmarker from 0.23.4 to 0.23.6 in /docs (#10722)
Summary:
Bumps [commonmarker](https://github.com/gjtorikian/commonmarker) from 0.23.4 to 0.23.6.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/gjtorikian/commonmarker/releases">commonmarker's releases</a>.</em></p>
<blockquote>
<h2>v0.23.6</h2>
<h2>What's Changed</h2>
<p>This release includes two updates from the upstream <code>cmark-gfm</code> library, namely:</p>
<ul>
<li><a href="https://github.com/github/cmark-gfm/releases">DoS vulnerability in autolink extension</a> per <a href="https://github.com/github/cmark-gfm/security/advisories/GHSA-cgh3-p57x-9q7q">GHSA-cgh3-p57x-9q7q</a></li>
<li><a href="https://github.com/github/cmark-gfm/releases/tag/0.29.0.gfm.5">Added <code>xmpp:</code> and <code>mailto:</code> support to the autolink extension</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/gjtorikian/commonmarker/blob/main/CHANGELOG.md">commonmarker's changelog</a>.</em></p>
<blockquote>
<h1>Changelog</h1>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="a8f8d76fbc"><code>a8f8d76</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/gjtorikian/commonmarker/issues/190">https://github.com/facebook/rocksdb/issues/190</a> from anticomputer/main</li>
<li><a href="ac91634631"><code>ac91634</code></a> 💎 release 0.23.6</li>
<li><a href="777fd3054b"><code>777fd30</code></a> Update cmark-upstream to <a href="https://github.com/github/cmark-gfm/commit/9d57d8a23">https://github.com/github/cmark-gfm/commit/9d57d8a23</a>...</li>
<li><a href="7aaeb37e97"><code>7aaeb37</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/gjtorikian/commonmarker/issues/188">https://github.com/facebook/rocksdb/issues/188</a> from stevenlaidlaw/update-to-0290gfm5</li>
<li><a href="795e628a40"><code>795e628</code></a> Update cmark-upstream to <a href="https://github.com/github/cmark-gfm/commit/0578e1e4f">https://github.com/github/cmark-gfm/commit/0578e1e4f</a>...</li>
<li><a href="39d19d6530"><code>39d19d6</code></a> Update cmark-upstream to <a href="https://github.com/github/cmark-gfm/commit/766f161ef">https://github.com/github/cmark-gfm/commit/766f161ef</a>...</li>
<li><a href="63b7bf89ee"><code>63b7bf8</code></a> Update FUNDING.yml</li>
<li><a href="558c7275b1"><code>558c727</code></a> Bump to 0.23.5</li>
<li><a href="41eee7265f"><code>41eee72</code></a> lint</li>
<li><a href="897e8ed07d"><code>897e8ed</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/gjtorikian/commonmarker/issues/180">https://github.com/facebook/rocksdb/issues/180</a> from lumaxis/main</li>
<li>Additional commits viewable in <a href="https://github.com/gjtorikian/commonmarker/compare/v0.23.4...v0.23.6">compare view</a></li>
</ul>
</details>
<br />

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Pull Request resolved: https://github.com/facebook/rocksdb/pull/10722

Reviewed By: riversand963

Differential Revision: D39735507

Pulled By: ajkr

fbshipit-source-id: 3a54f9542a3d2b88c2993dd8a125b0e7f990a886
2022-09-22 16:20:08 -07:00
Peter Dillinger ef443cead4 Refactor to avoid confusing "raw block" (#10408)
Summary:
We have a lot of confusing code because of mixed, sometimes
completely opposite uses of of the term "raw block" or "raw contents",
sometimes within the same source file. For example, in `BlockBasedTableBuilder`,
`raw_block_contents` and `raw_size` generally referred to uncompressed block
contents and size, while `WriteRawBlock` referred to writing a block that
is already compressed if it is going to be. Meanwhile, in
`BlockBasedTable`, `raw_block_contents` either referred to a (maybe
compressed) block with trailer, or a maybe compressed block maybe
without trailer. (Note: left as follow-up work to use C++ typing to
better sort out the various kinds of BlockContents.)

This change primarily tries to apply some consistent terminology around
the kinds of block representations, avoiding the unclear "raw". (Any
meaning of "raw" assumes some bias toward the storage layer or toward
the logical data layer.) Preferred terminology:

* **Serialized block** - bytes that go into storage. For block-based table
(usually the case) this includes the block trailer. WART: block `size` may or
may not include the trailer; need to be clear about whether it does or not.
* **Maybe compressed block** - like a serialized block, but without the
trailer (or no promise of including a trailer). Must be accompanied by a
CompressionType.
* **Uncompressed block** - "payload" bytes that are either stored with no
compression, used as input to compression function, or result of
decompression function.
* **Parsed block** - an in-memory form of a block in block cache, as it is
used by the table reader. Different C++ types are used depending on the
block type (see block_like_traits.h).

Other refactorings:
* Misc corrections/improvements of internal API comments
* Remove a few misleading / unhelpful / redundant comments.
* Use move semantics in some places to simplify contracts
* Use better parameter names to indicate which parameters are used for
outputs
* Remove some extraneous `extern`
* Various clean-ups to `CacheDumperImpl` (mostly unnecessary code)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10408

Test Plan: existing tests

Reviewed By: akankshamahajan15

Differential Revision: D38172617

Pulled By: pdillinger

fbshipit-source-id: ccb99299f324ac5ca46996d34c5089621a4f260c
2022-09-22 11:25:32 -07:00
Levi Tamasi 12f5a1e35c Clarify comments for cache priorities and pool options (#10718)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/10718

Reviewed By: riversand963

Differential Revision: D39707115

Pulled By: ltamasi

fbshipit-source-id: 59aec8c732482f063d0abaad4d9200ba57ebf437
2022-09-21 16:02:08 -07:00
Changyu Bi 93f46da1fa Mention in HISTORY.md the fix in #10705 (#10720)
Summary:
Mention in HISTORY.md the fix in https://github.com/facebook/rocksdb/issues/10705.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10720

Reviewed By: riversand963

Differential Revision: D39709455

Pulled By: cbi42

fbshipit-source-id: 1a2c9dd8425c73f7095ddb1d0b1cca8ed35b7ef2
2022-09-21 15:08:43 -07:00
anand76 fb9a025892 Fix platform 10 build with folly (#10708)
Summary:
Change the library order in PLATFORM_LDFLAGS to enable fbcode platform 10 build with folly. This PR also has a few fixes for platform 10 compiler errors.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10708

Test Plan:
ROCKSDB_FBCODE_BUILD_WITH_PLATFORM010=1 USE_COROUTINES=1 make -j64 check
ROCKSDB_FBCODE_BUILD_WITH_PLATFORM010=1 USE_FOLLY=1 make -j64 check

Reviewed By: ajkr

Differential Revision: D39666590

Pulled By: anand1976

fbshipit-source-id: 256a1127ef561399cd6299a6a392ca29bd68ca44
2022-09-21 14:43:44 -07:00
Akanksha Mahajan 0f4978d34f Fix sqe->addr passed in cancel request in io_uring (#10644)
Summary:
Update io_uring_prep_cancel as it is now backward compatible.
Also, io_uring_prep_cancel expects sqe->addr to match with read
request submitted. It's being set wrong which is now fixed in this PR.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10644

Test Plan:
- Ran internally with lastest liburing package and on RocksDB
github repo with older version.
- Ran seekrandom regression to confirm there is no regression.

Reviewed By: anand1976

Differential Revision: D39284229

Pulled By: akankshamahajan15

fbshipit-source-id: fd52cdf23d676da114896163626b75c8ae09c980
2022-09-21 14:21:59 -07:00
Changyu Bi 013305af13 Fix potential memory leak in ArenaWrappedDBIter::Refresh() (#10716)
Summary:
Fix potential memory leak in ArenaWrappedDBIter::Refresh() introduced in https://github.com/facebook/rocksdb/issues/10705. See https://github.com/facebook/rocksdb/pull/10705#discussion_r976765905 for detail.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10716

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D39698561

Pulled By: cbi42

fbshipit-source-id: dc0d0c6e3878eaa84f87623fbe4916b9b08b077a
2022-09-21 14:08:10 -07:00
Bo Wang dd40f83e95 Fix lint issues after enable BLACK (#10717)
Summary:
As title

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10717

Test Plan:
Unit Tests
CI

Reviewed By: riversand963

Differential Revision: D39700707

Pulled By: gitbw95

fbshipit-source-id: 54de27e695535a50159f5f6467da36aaf21bebae
2022-09-21 13:37:51 -07:00
Changyu Bi 749b849a34 Fix memtable-only iterator regression (#10705)
Summary:
when there is a single memtable without range tombstones and no SST files in the database, DBIter should wrap memtable iterator directly. Currently we create a merging iterator on top of the memtable iterator, and have DBIter wrap around it. This causes iterator regression and this PR fixes this issue.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10705

Test Plan:
- `make check`
- Performance:
  - Set up: `./db_bench -benchmarks=filluniquerandom -write_buffer_size=$((1 << 30)) -num=10000`
  - Benchmark: `./db_bench -benchmarks=seekrandom -use_existing_db=true -avoid_flush_during_recovery=true -write_buffer_size=$((1 << 30)) -num=10000 -threads=16 -duration=60 -seek_nexts=$seek_nexts`
```
seek_nexts    main op/sec    https://github.com/facebook/rocksdb/issues/10705      RocksDB v7.6
0             5746568        5749033     5786180
30            2411690        3006466     2837699
1000          102556         128902      124667
```

Reviewed By: ajkr

Differential Revision: D39644221

Pulled By: cbi42

fbshipit-source-id: 8063ff611ba31b0e5670041da3927c8c54b2097d
2022-09-21 09:49:31 -07:00
Bo Wang 9e01de9066 Enable BLACK for internal_repo_rocksdb (#10710)
Summary:
Enable BLACK for internal_repo_rocksdb.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10710

Reviewed By: riversand963, zsol

Differential Revision: D39666245

Pulled By: gitbw95

fbshipit-source-id: ef364318d2bbba66e96f3211dd6a975174d52c21
2022-09-20 17:47:52 -07:00
Jay Zhuang 00050d4634 Disable tiered storage + BlobDB stress test (#10699)
Summary:
There're 2 knobs to disable blobdb, adding that.
Also print call stack when there's assert failure.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10699

Reviewed By: gitbw95

Differential Revision: D39596448

Pulled By: jay-zhuang

fbshipit-source-id: 5ce9fd0630d8b6ff1e157a2685a1e80a99997098
2022-09-19 15:39:31 -07:00
Jay Zhuang 92df36985d Deflake CompactionServiceTest.BasicCompactions (#10697)
Summary:
The background compaction may still running while the test end, which would cause ASAN stack-use-after-scope error.
Explicitly close the DB before test end.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10697

Test Plan:
able to reproduce with:
```
gtest-parallel ./compaction_service_test --gtest_filter=CompactionServiceTest.BasicCompactions -r 10000 -w 100
```

Reviewed By: gitbw95

Differential Revision: D39590974

Pulled By: jay-zhuang

fbshipit-source-id: da264b2e6a276afbda7d5ff7adb9d7b8d4213d90
2022-09-19 14:10:05 -07:00
Yanqin Jin 2b6f3510c2 Update version number and HISTORY in main branch (#10694)
Summary:
This PR bumps up version number from 7.7 to 7.8 in main branch, indicating that next release will be 7.8. We are going to release 7.7 soon. Since 7.7.fb branch has been created, we can land this to main.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10694

Reviewed By: gitbw95

Differential Revision: D39581577

Pulled By: riversand963

fbshipit-source-id: 84f3fecf25fd9ac96e46b4cd6d50ddb6edc89427
2022-09-19 12:25:44 -07:00
anand76 01ebe8a5f7 Fix invalid reference in MultiGet due to vector resizing (#10702)
Summary:
Fix invalid reference in MultiGet due to resizing of the ```batches``` autovector.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10702

Test Plan: Run asan crash test

Reviewed By: riversand963

Differential Revision: D39608753

Pulled By: anand1976

fbshipit-source-id: 7a9e7fc6f436f08eb22003d0e6b0e1e4dcdc1a2a
2022-09-18 19:00:48 -07:00
gitbw95 2cc5b39560 Add enable_split_merge option for CompressedSecondaryCache (#10690)
Summary:
`enable_custom_split_merge` is added for enabling the custom split and merge feature, which split the compressed value into chunks so that they may better fit jemalloc bins.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10690

Test Plan:
Unit Tests
Stress Tests

Reviewed By: anand1976

Differential Revision: D39567604

Pulled By: gitbw95

fbshipit-source-id: f6d1d46200f365220055f793514601dcb0edc4b7
2022-09-16 15:41:49 -07:00
anand76 e053ccde99 Fix an incorrect MultiGet assertion (#10695)
Summary:
The assertion in ```FilePickerMultiGet::ReplaceRange()``` was incorrect. The function should only be called to replace the range after finishing the search in the current level, which is indicated by ```hit_file_ == nullptr``` i.e no more overlapping files in this level.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10695

Reviewed By: gitbw95

Differential Revision: D39583217

Pulled By: anand1976

fbshipit-source-id: d4cedfb2b62fb9f3a083e9848a403ae6342f0519
2022-09-16 13:18:42 -07:00
Peter Dillinger 0f91c72adc Call experimental new clock cache HyperClockCache (#10684)
Summary:
This change establishes a distinctive name for the experimental new lock-free clock cache (originally developed by guidotag and revamped in PR https://github.com/facebook/rocksdb/issues/10626). A few reasons:
* We want to make it clear that this is a fundamentally different implementation vs. the old clock cache, to avoid people saying "I already tried clock cache."
* We want to highlight the key feature: it's fast (especially under parallel load)
* Because it requires an estimated charge per entry, it is not drop-in API compatible with old clock cache. This estimate might always be required for highest performance, and giving it a distinct name should reduce confusion about the distinct API requirements.
* We might develop a variant requiring the same estimate parameter but with LRU eviction. In that case, using the name HyperLRUCache should make things more clear. (FastLRUCache is just a prototype that might soon be removed.)

Some API detail:
* To reduce copy-pasting parameter lists, etc. as in LRUCache construction, I have a `MakeSharedCache()` function on `HyperClockCacheOptions` instead of `NewHyperClockCache()`.
* Changes -cache_type=clock_cache to -cache_type=hyper_clock_cache for applicable tools. I think this is more consistent / sustainable for reasons already stated.

For performance tests see https://github.com/facebook/rocksdb/pull/10626

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10684

Test Plan: no interesting functional changes; tests updated

Reviewed By: anand1976

Differential Revision: D39547800

Pulled By: pdillinger

fbshipit-source-id: 5c0fe1b5cf3cb680ab369b928c8569682b9795bf
2022-09-16 12:47:29 -07:00
Peter Dillinger 5724348689 Revamp, optimize new experimental clock cache (#10626)
Summary:
* Consolidates most metadata into a single word per slot so that more
can be accomplished with a single atomic update. In the common case,
Lookup was previously about 4 atomic updates, now just 1 atomic update.
Common case Release was previously 1 atomic read + 1 atomic update,
now just 1 atomic update.
* Eliminate spins / waits / yields, which likely threaten some "lock free"
benefits. Compare-exchange loops are only used in explicit Erase, and
strict_capacity_limit=true Insert. Eviction uses opportunistic compare-
exchange.
* Relaxes some aggressiveness and guarantees. For example,
  * Duplicate Inserts will sometimes go undetected and the shadow duplicate
    will age out with eviction.
  * In many cases, the older Inserted value for a given cache key will be kept
  (i.e. Insert does not support overwrite).
  * Entries explicitly erased (rather than evicted) might not be freed
  immediately in some rare cases.
  * With strict_capacity_limit=false, capacity limit is not tracked/enforced as
  precisely as LRUCache, but is self-correcting and should only deviate by a
  very small number of extra or fewer entries.
* Use smaller "computed default" number of cache shards in many cases,
because benefits to larger usage tracking / eviction pools outweigh the small
cost of more lock-free atomic contention. The improvement in CPU and I/O
is dramatic in some limit-memory cases.
* Even without the sharding change, the eviction algorithm is likely more
effective than LRU overall because it's more stateful, even though the
"hot path" state tracking for it is essentially free with ref counting. It
is like a generalized CLOCK with aging (see code comments). I don't have
performance numbers showing a specific improvement, but in theory, for a
Poisson access pattern to each block, keeping some state allows better
estimation of time to next access (Poisson interval) than strict LRU. The
bounded randomness in CLOCK can also reduce "cliff" effect for repeated
range scans approaching and exceeding cache size.

## Hot path algorithm comparison
Rough descriptions, focusing on number and kind of atomic operations:
* Old `Lookup()` (2-5 atomic updates per probe):
```
Loop:
  Increment internal ref count at slot
  If possible hit:
    Check flags atomic (and non-atomic fields)
    If cache hit:
      Three distinct updates to 'flags' atomic
      Increment refs for internal-to-external
      Return
  Decrement internal ref count
while atomic read 'displacements' > 0
```
* New `Lookup()` (1-2 atomic updates per probe):
```
Loop:
  Increment acquire counter in meta word (optimistic)
  If visible entry (already read meta word):
    If match (read non-atomic fields):
      Return
    Else:
      Decrement acquire counter in meta word
  Else if invisible entry (rare, already read meta word):
    Decrement acquire counter in meta word
while atomic read 'displacements' > 0
```
* Old `Release()` (1 atomic update, conditional on atomic read, rarely more):
```
Read atomic ref count
If last reference and invisible (rare):
  Use CAS etc. to remove
  Return
Else:
  Decrement ref count
```
* New `Release()` (1 unconditional atomic update, rarely more):
```
Increment release counter in meta word
If last reference and invisible (rare):
  Use CAS etc. to remove
  Return
```

## Performance test setup
Build DB 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 -readonly -num=30000000 -bloom_bits=16 -cache_index_and_filter_blocks=1 -cache_size=${CACHE_MB}000000 -duration 60 -threads=$THREADS -statistics
```
Numbers on a single socket Skylake Xeon system with 48 hardware threads, DEBUG_LEVEL=0 PORTABLE=0. Very similar story on a dual socket system with 80 hardware threads. Using (every 2nd) Fibonacci MB cache sizes to sample the territory between powers of two. Configurations:

base: LRUCache before this change, but with db_bench change to default cache_numshardbits=-1 (instead of fixed at 6)
folly: LRUCache before this change, with folly enabled (distributed mutex) but on an old compiler (sorry)
gt_clock: experimental ClockCache before this change
new_clock: experimental ClockCache with this change

## Performance test results
First test "hot path" read performance, with block cache large enough for whole DB:
4181MB 1thread base -> kops/s: 47.761
4181MB 1thread folly -> kops/s: 45.877
4181MB 1thread gt_clock -> kops/s: 51.092
4181MB 1thread new_clock -> kops/s: 53.944

4181MB 16thread base -> kops/s: 284.567
4181MB 16thread folly -> kops/s: 249.015
4181MB 16thread gt_clock -> kops/s: 743.762
4181MB 16thread new_clock -> kops/s: 861.821

4181MB 24thread base -> kops/s: 303.415
4181MB 24thread folly -> kops/s: 266.548
4181MB 24thread gt_clock -> kops/s: 975.706
4181MB 24thread new_clock -> kops/s: 1205.64 (~= 24 * 53.944)

4181MB 32thread base -> kops/s: 311.251
4181MB 32thread folly -> kops/s: 274.952
4181MB 32thread gt_clock -> kops/s: 1045.98
4181MB 32thread new_clock -> kops/s: 1370.38

4181MB 48thread base -> kops/s: 310.504
4181MB 48thread folly -> kops/s: 268.322
4181MB 48thread gt_clock -> kops/s: 1195.65
4181MB 48thread new_clock -> kops/s: 1604.85 (~= 24 * 1.25 * 53.944)

4181MB 64thread base -> kops/s: 307.839
4181MB 64thread folly -> kops/s: 272.172
4181MB 64thread gt_clock -> kops/s: 1204.47
4181MB 64thread new_clock -> kops/s: 1615.37

4181MB 128thread base -> kops/s: 310.934
4181MB 128thread folly -> kops/s: 267.468
4181MB 128thread gt_clock -> kops/s: 1188.75
4181MB 128thread new_clock -> kops/s: 1595.46

Whether we have just one thread on a quiet system or an overload of threads, the new version wins every time in thousand-ops per second, sometimes dramatically so. Mutex-based implementation quickly becomes contention-limited. New clock cache shows essentially perfect scaling up to number of physical cores (24), and then each hyperthreaded core adding about 1/4 the throughput of an additional physical core (see 48 thread case). Block cache miss rates (omitted above) are negligible across the board. With partitioned instead of full filters, the maximum speed-up vs. base is more like 2.5x rather than 5x.

Now test a large block cache with low miss ratio, but some eviction is required:
1597MB 1thread base -> kops/s: 46.603 io_bytes/op: 1584.63 miss_ratio: 0.0201066 max_rss_mb: 1589.23
1597MB 1thread folly -> kops/s: 45.079 io_bytes/op: 1530.03 miss_ratio: 0.019872 max_rss_mb: 1550.43
1597MB 1thread gt_clock -> kops/s: 48.711 io_bytes/op: 1566.63 miss_ratio: 0.0198923 max_rss_mb: 1691.4
1597MB 1thread new_clock -> kops/s: 51.531 io_bytes/op: 1589.07 miss_ratio: 0.0201969 max_rss_mb: 1583.56

1597MB 32thread base -> kops/s: 301.174 io_bytes/op: 1439.52 miss_ratio: 0.0184218 max_rss_mb: 1656.59
1597MB 32thread folly -> kops/s: 273.09 io_bytes/op: 1375.12 miss_ratio: 0.0180002 max_rss_mb: 1586.8
1597MB 32thread gt_clock -> kops/s: 904.497 io_bytes/op: 1411.29 miss_ratio: 0.0179934 max_rss_mb: 1775.89
1597MB 32thread new_clock -> kops/s: 1182.59 io_bytes/op: 1440.77 miss_ratio: 0.0185449 max_rss_mb: 1636.45

1597MB 128thread base -> kops/s: 309.91 io_bytes/op: 1438.25 miss_ratio: 0.018399 max_rss_mb: 1689.98
1597MB 128thread folly -> kops/s: 267.605 io_bytes/op: 1394.16 miss_ratio: 0.0180286 max_rss_mb: 1631.91
1597MB 128thread gt_clock -> kops/s: 691.518 io_bytes/op: 9056.73 miss_ratio: 0.0186572 max_rss_mb: 1982.26
1597MB 128thread new_clock -> kops/s: 1406.12 io_bytes/op: 1440.82 miss_ratio: 0.0185463 max_rss_mb: 1685.63

610MB 1thread base -> kops/s: 45.511 io_bytes/op: 2279.61 miss_ratio: 0.0290528 max_rss_mb: 615.137
610MB 1thread folly -> kops/s: 43.386 io_bytes/op: 2217.29 miss_ratio: 0.0289282 max_rss_mb: 600.996
610MB 1thread gt_clock -> kops/s: 46.207 io_bytes/op: 2275.51 miss_ratio: 0.0290057 max_rss_mb: 637.934
610MB 1thread new_clock -> kops/s: 48.879 io_bytes/op: 2283.1 miss_ratio: 0.0291253 max_rss_mb: 613.5

610MB 32thread base -> kops/s: 306.59 io_bytes/op: 2250 miss_ratio: 0.0288721 max_rss_mb: 683.402
610MB 32thread folly -> kops/s: 269.176 io_bytes/op: 2187.86 miss_ratio: 0.0286938 max_rss_mb: 628.742
610MB 32thread gt_clock -> kops/s: 855.097 io_bytes/op: 2279.26 miss_ratio: 0.0288009 max_rss_mb: 733.062
610MB 32thread new_clock -> kops/s: 1121.47 io_bytes/op: 2244.29 miss_ratio: 0.0289046 max_rss_mb: 666.453

610MB 128thread base -> kops/s: 305.079 io_bytes/op: 2252.43 miss_ratio: 0.0288884 max_rss_mb: 723.457
610MB 128thread folly -> kops/s: 269.583 io_bytes/op: 2204.58 miss_ratio: 0.0287001 max_rss_mb: 676.426
610MB 128thread gt_clock -> kops/s: 53.298 io_bytes/op: 8128.98 miss_ratio: 0.0292452 max_rss_mb: 956.273
610MB 128thread new_clock -> kops/s: 1301.09 io_bytes/op: 2246.04 miss_ratio: 0.0289171 max_rss_mb: 788.812

The new version is still winning every time, sometimes dramatically so, and we can tell from the maximum resident memory numbers (which contain some noise, by the way) that the new cache is not cheating on memory usage. IMPORTANT: The previous generation experimental clock cache appears to hit a serious bottleneck in the higher thread count configurations, presumably due to some of its waiting functionality. (The same bottleneck is not seen with partitioned index+filters.)

Now we consider even smaller cache sizes, with higher miss ratios, eviction work, etc.

233MB 1thread base -> kops/s: 10.557 io_bytes/op: 227040 miss_ratio: 0.0403105 max_rss_mb: 247.371
233MB 1thread folly -> kops/s: 15.348 io_bytes/op: 112007 miss_ratio: 0.0372238 max_rss_mb: 245.293
233MB 1thread gt_clock -> kops/s: 6.365 io_bytes/op: 244854 miss_ratio: 0.0413873 max_rss_mb: 259.844
233MB 1thread new_clock -> kops/s: 47.501 io_bytes/op: 2591.93 miss_ratio: 0.0330989 max_rss_mb: 242.461

233MB 32thread base -> kops/s: 96.498 io_bytes/op: 363379 miss_ratio: 0.0459966 max_rss_mb: 479.227
233MB 32thread folly -> kops/s: 109.95 io_bytes/op: 314799 miss_ratio: 0.0450032 max_rss_mb: 400.738
233MB 32thread gt_clock -> kops/s: 2.353 io_bytes/op: 385397 miss_ratio: 0.048445 max_rss_mb: 500.688
233MB 32thread new_clock -> kops/s: 1088.95 io_bytes/op: 2567.02 miss_ratio: 0.0330593 max_rss_mb: 303.402

233MB 128thread base -> kops/s: 84.302 io_bytes/op: 378020 miss_ratio: 0.0466558 max_rss_mb: 1051.84
233MB 128thread folly -> kops/s: 89.921 io_bytes/op: 338242 miss_ratio: 0.0460309 max_rss_mb: 812.785
233MB 128thread gt_clock -> kops/s: 2.588 io_bytes/op: 462833 miss_ratio: 0.0509158 max_rss_mb: 1109.94
233MB 128thread new_clock -> kops/s: 1299.26 io_bytes/op: 2565.94 miss_ratio: 0.0330531 max_rss_mb: 361.016

89MB 1thread base -> kops/s: 0.574 io_bytes/op: 5.35977e+06 miss_ratio: 0.274427 max_rss_mb: 91.3086
89MB 1thread folly -> kops/s: 0.578 io_bytes/op: 5.16549e+06 miss_ratio: 0.27276 max_rss_mb: 96.8984
89MB 1thread gt_clock -> kops/s: 0.512 io_bytes/op: 4.13111e+06 miss_ratio: 0.242817 max_rss_mb: 119.441
89MB 1thread new_clock -> kops/s: 48.172 io_bytes/op: 2709.76 miss_ratio: 0.0346162 max_rss_mb: 100.754

89MB 32thread base -> kops/s: 5.779 io_bytes/op: 6.14192e+06 miss_ratio: 0.320399 max_rss_mb: 311.812
89MB 32thread folly -> kops/s: 5.601 io_bytes/op: 5.83838e+06 miss_ratio: 0.313123 max_rss_mb: 252.418
89MB 32thread gt_clock -> kops/s: 0.77 io_bytes/op: 3.99236e+06 miss_ratio: 0.236296 max_rss_mb: 396.422
89MB 32thread new_clock -> kops/s: 1064.97 io_bytes/op: 2687.23 miss_ratio: 0.0346134 max_rss_mb: 155.293

89MB 128thread base -> kops/s: 4.959 io_bytes/op: 6.20297e+06 miss_ratio: 0.323945 max_rss_mb: 823.43
89MB 128thread folly -> kops/s: 4.962 io_bytes/op: 5.9601e+06 miss_ratio: 0.319857 max_rss_mb: 626.824
89MB 128thread gt_clock -> kops/s: 1.009 io_bytes/op: 4.1083e+06 miss_ratio: 0.242512 max_rss_mb: 1095.32
89MB 128thread new_clock -> kops/s: 1224.39 io_bytes/op: 2688.2 miss_ratio: 0.0346207 max_rss_mb: 218.223

^ Now something interesting has happened: the new clock cache has gained a dramatic lead in the single-threaded case, and this is because the cache is so small, and full filters are so big, that dividing the cache into 64 shards leads to significant (random) imbalances in cache shards and excessive churn in imbalanced shards. This new clock cache only uses two shards for this configuration, and that helps to ensure that entries are part of a sufficiently big pool that their eviction order resembles the single-shard order. (This effect is not seen with partitioned index+filters.)

Even smaller cache size:
34MB 1thread base -> kops/s: 0.198 io_bytes/op: 1.65342e+07 miss_ratio: 0.939466 max_rss_mb: 48.6914
34MB 1thread folly -> kops/s: 0.201 io_bytes/op: 1.63416e+07 miss_ratio: 0.939081 max_rss_mb: 45.3281
34MB 1thread gt_clock -> kops/s: 0.448 io_bytes/op: 4.43957e+06 miss_ratio: 0.266749 max_rss_mb: 100.523
34MB 1thread new_clock -> kops/s: 1.055 io_bytes/op: 1.85439e+06 miss_ratio: 0.107512 max_rss_mb: 75.3125

34MB 32thread base -> kops/s: 3.346 io_bytes/op: 1.64852e+07 miss_ratio: 0.93596 max_rss_mb: 180.48
34MB 32thread folly -> kops/s: 3.431 io_bytes/op: 1.62857e+07 miss_ratio: 0.935693 max_rss_mb: 137.531
34MB 32thread gt_clock -> kops/s: 1.47 io_bytes/op: 4.89704e+06 miss_ratio: 0.295081 max_rss_mb: 392.465
34MB 32thread new_clock -> kops/s: 8.19 io_bytes/op: 3.70456e+06 miss_ratio: 0.20826 max_rss_mb: 519.793

34MB 128thread base -> kops/s: 2.293 io_bytes/op: 1.64351e+07 miss_ratio: 0.931866 max_rss_mb: 449.484
34MB 128thread folly -> kops/s: 2.34 io_bytes/op: 1.6219e+07 miss_ratio: 0.932023 max_rss_mb: 396.457
34MB 128thread gt_clock -> kops/s: 1.798 io_bytes/op: 5.4241e+06 miss_ratio: 0.324881 max_rss_mb: 1104.41
34MB 128thread new_clock -> kops/s: 10.519 io_bytes/op: 2.39354e+06 miss_ratio: 0.136147 max_rss_mb: 1050.52

As the miss ratio gets higher (say, above 10%), the CPU time spent in eviction starts to erode the advantage of using fewer shards (13% miss rate much lower than 94%). LRU's O(1) eviction time can eventually pay off when there's enough block cache churn:

13MB 1thread base -> kops/s: 0.195 io_bytes/op: 1.65732e+07 miss_ratio: 0.946604 max_rss_mb: 45.6328
13MB 1thread folly -> kops/s: 0.197 io_bytes/op: 1.63793e+07 miss_ratio: 0.94661 max_rss_mb: 33.8633
13MB 1thread gt_clock -> kops/s: 0.519 io_bytes/op: 4.43316e+06 miss_ratio: 0.269379 max_rss_mb: 100.684
13MB 1thread new_clock -> kops/s: 0.176 io_bytes/op: 1.54148e+07 miss_ratio: 0.91545 max_rss_mb: 66.2383

13MB 32thread base -> kops/s: 3.266 io_bytes/op: 1.65544e+07 miss_ratio: 0.943386 max_rss_mb: 132.492
13MB 32thread folly -> kops/s: 3.396 io_bytes/op: 1.63142e+07 miss_ratio: 0.943243 max_rss_mb: 101.863
13MB 32thread gt_clock -> kops/s: 2.758 io_bytes/op: 5.13714e+06 miss_ratio: 0.310652 max_rss_mb: 396.121
13MB 32thread new_clock -> kops/s: 3.11 io_bytes/op: 1.23419e+07 miss_ratio: 0.708425 max_rss_mb: 321.758

13MB 128thread base -> kops/s: 2.31 io_bytes/op: 1.64823e+07 miss_ratio: 0.939543 max_rss_mb: 425.539
13MB 128thread folly -> kops/s: 2.339 io_bytes/op: 1.6242e+07 miss_ratio: 0.939966 max_rss_mb: 346.098
13MB 128thread gt_clock -> kops/s: 3.223 io_bytes/op: 5.76928e+06 miss_ratio: 0.345899 max_rss_mb: 1087.77
13MB 128thread new_clock -> kops/s: 2.984 io_bytes/op: 1.05341e+07 miss_ratio: 0.606198 max_rss_mb: 898.27

gt_clock is clearly blowing way past its memory budget for lower miss rates and best throughput. new_clock also seems to be exceeding budgets, and this warrants more investigation but is not the use case we are targeting with the new cache. With partitioned index+filter, the miss ratio is much better, and although still high enough that the eviction CPU time is definitely offsetting mutex contention:

13MB 1thread base -> kops/s: 16.326 io_bytes/op: 23743.9 miss_ratio: 0.205362 max_rss_mb: 65.2852
13MB 1thread folly -> kops/s: 15.574 io_bytes/op: 19415 miss_ratio: 0.184157 max_rss_mb: 56.3516
13MB 1thread gt_clock -> kops/s: 14.459 io_bytes/op: 22873 miss_ratio: 0.198355 max_rss_mb: 63.9688
13MB 1thread new_clock -> kops/s: 16.34 io_bytes/op: 24386.5 miss_ratio: 0.210512 max_rss_mb: 61.707

13MB 128thread base -> kops/s: 289.786 io_bytes/op: 23710.9 miss_ratio: 0.205056 max_rss_mb: 103.57
13MB 128thread folly -> kops/s: 185.282 io_bytes/op: 19433.1 miss_ratio: 0.184275 max_rss_mb: 116.219
13MB 128thread gt_clock -> kops/s: 354.451 io_bytes/op: 23150.6 miss_ratio: 0.200495 max_rss_mb: 102.871
13MB 128thread new_clock -> kops/s: 295.359 io_bytes/op: 24626.4 miss_ratio: 0.212452 max_rss_mb: 121.109

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10626

Test Plan: updated unit tests, stress/crash test runs including with TSAN, ASAN, UBSAN

Reviewed By: anand1976

Differential Revision: D39368406

Pulled By: pdillinger

fbshipit-source-id: 5afc44da4c656f8f751b44552bbf27bd3ca6fef9
2022-09-16 00:24:11 -07:00
anand76 37b75e1364 Fix some MultiGet stats (#10673)
Summary:
The stats were not accurate for the coroutine version of MultiGet. This PR fixes it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10673

Reviewed By: akankshamahajan15

Differential Revision: D39492615

Pulled By: anand1976

fbshipit-source-id: b46c04e15ea27e66f4c31f00c66497aa283bf9d3
2022-09-15 22:48:06 -07:00
Yanqin Jin 088b9844d4 Re-enable user-defined timestamp and subcompactions (#10689)
Summary:
Hopefully, we can re-enable the combination of user-defined timestamp and subcompactions
after https://github.com/facebook/rocksdb/issues/10658.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10689

Test Plan:
Make sure the following succeeds on devserver.
make crash_test_with_ts

Reviewed By: ltamasi

Differential Revision: D39556558

Pulled By: riversand963

fbshipit-source-id: 4695f420b1bc9ebf3b24640b693746f4db82c149
2022-09-15 20:21:07 -07:00
anand76 c206aebd0b Fix a MultiGet crash (#10688)
Summary:
Fix a bug in the async IO/coroutine version of MultiGet that may cause a segfault or assertion failure due to accessing an invalid file index in a LevelFilesBrief. The bug is that when a MultiGetRange is split into two, we may re-process keys in the original range that were already marked to be skipped (in ```current_level_range_```) due to not overlapping the level.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10688

Reviewed By: gitbw95

Differential Revision: D39556131

Pulled By: anand1976

fbshipit-source-id: 65e79438508a283cb19e64eca5c91d0714b81458
2022-09-15 19:18:52 -07:00
Andrew Kryczka 6ce782beaf move db_stress locking to `StressTest::Test*()` functions (#10678)
Summary:
One problem of the previous strategy was `NonBatchedOpsStressTest::TestIngestExternalFile()` could release the lock for `rand_keys[0]` in `rand_column_families[0]`, and then subsequent operations in the same loop iteration (e.g., `TestPut()`) would run without locking. This PR changes the strategy so each `Test*()` function is responsible for acquiring and releasing its own locks.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10678

Reviewed By: hx235

Differential Revision: D39516401

Pulled By: ajkr

fbshipit-source-id: bf67f12ebbd293ba8c24fdf8754ff28737bcd758
2022-09-15 15:55:37 -07:00
Levi Tamasi 7dad485278 Support JemallocNodumpAllocator for the block/blob cache in db_bench (#10685)
Summary:
The patch makes it possible to use the `JemallocNodumpAllocator` with the
block/blob caches in `db_bench`. In addition to its stated purpose of excluding
cache contents from core dumps, `JemallocNodumpAllocator` also uses
a dedicated arena and jemalloc tcaches for cache allocations, which can
reduce fragmentation and thus memory usage.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10685

Reviewed By: riversand963

Differential Revision: D39552261

Pulled By: ltamasi

fbshipit-source-id: b5c58eab6b7c1baa9a307d9f1248df1d7a77d2b5
2022-09-15 13:44:46 -07:00
Bo Wang b418ace352 Disable PersistentCacheTierTest.BasicTest (#10683)
Summary:
Disable this flaky test since PersistentCache is not used.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10683

Test Plan: Unit Tests

Reviewed By: cbi42

Differential Revision: D39545974

Pulled By: gitbw95

fbshipit-source-id: ac53e96f6ba880e7612e325eb5ff22ee2799efed
2022-09-15 11:14:48 -07:00
Jay Zhuang 1cdc84114f Tiered Storage feature doesn't support BlobDB yet (#10681)
Summary:
Disable the tiered storage + BlobDB test.
Also enable different hot data setting for Tiered compaction

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10681

Reviewed By: ajkr

Differential Revision: D39531941

Pulled By: jay-zhuang

fbshipit-source-id: aa0595eb38d03f17638d300d2e4cc9061429bf61
2022-09-15 08:17:16 -07:00
Jay Zhuang 849cf1bf68 Refactor Compaction file cut `ShouldStopBefore()` (#10629)
Summary:
Consolidate compaction output cut logic to `ShouldStopBefore()` and move
it inside of CompactionOutputs class.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10629

Reviewed By: cbi42

Differential Revision: D39315536

Pulled By: jay-zhuang

fbshipit-source-id: 7d81037babbd35c276bbaad02dbc2bb555fdac18
2022-09-14 22:09:12 -07:00
Yanqin Jin ce2c11d848 Fix a bug by setting up subcompaction bounds properly (#10658)
Summary:
When user-defined timestamp is enabled, subcompaction bounds should be set up properly. When creating InputIterator for the compaction, the `start` and `end` should have their timestamp portions set to kMaxTimestamp, which is the highest possible timestamp. This is similar to what we do with setting up their sequence numbers to `kMaxSequenceNumber`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10658

Test Plan:
```bash
make check
rm -rf /dev/shm/rocksdb/* && mkdir
/dev/shm/rocksdb/rocksdb_crashtest_expected && ./db_stress
--allow_data_in_errors=True --clear_column_family_one_in=0
--continuous_verification_interval=0 --data_block_index_type=1
--db=/dev/shm/rocksdb//rocksdb_crashtest_blackbox --delpercent=5
--delrangepercent=0
--expected_values_dir=/dev/shm/rocksdb//rocksdb_crashtest_expected
--iterpercent=0 --max_background_compactions=20
--max_bytes_for_level_base=10485760 --max_key=25000000
--max_write_batch_group_size_bytes=1048576 --nooverwritepercent=1
--ops_per_thread=300000 --paranoid_file_checks=1 --partition_filters=0
--prefix_size=8 --prefixpercent=5 --readpercent=30 --reopen=0
--snapshot_hold_ops=100000 --subcompactions=4
--target_file_size_base=65536 --target_file_size_multiplier=2
--test_batches_snapshots=0 --test_cf_consistency=0 --use_multiget=1
--user_timestamp_size=8 --value_size_mult=32 --verify_checksum=1
--write_buffer_size=65536 --writepercent=60 -disable_wal=1
-column_families=1
```

Reviewed By: akankshamahajan15

Differential Revision: D39393402

Pulled By: riversand963

fbshipit-source-id: f276e35b19fce51a175c368a502fb0718d1f3871
2022-09-14 21:59:56 -07:00
Changyu Bi be04a3b6cd Fix data race in accessing `cached_range_tombstone_` (#10680)
Summary:
fix a data race introduced in https://github.com/facebook/rocksdb/issues/10547 (P5295241720), first reported by pdillinger. The race is between the `std::atomic_load_explicit` in NewRangeTombstoneIteratorInternal and the `std::atomic_store_explicit` in MemTable::Add() that operate on `cached_range_tombstone_`. P5295241720 shows that `atomic_store_explicit` initializes some mutex which `atomic_load_explicit` could be trying to call `lock()` on at the same time. This fix moves the initialization to memtable constructor.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10680

Test Plan: `USE_CLANG=1 COMPILE_WITH_TSAN=1 make -j24 whitebox_crash_test`

Reviewed By: ajkr

Differential Revision: D39528696

Pulled By: cbi42

fbshipit-source-id: ee740841044438e18ad2b8ea567444dd542dd8e2
2022-09-14 20:50:10 -07:00
Yanqin Jin 832fd644fc Reset pessimistic transaction's read/commit timestamps during Initialize() (#10677)
Summary:
RocksDB allows reusing old `Transaction` objects when creating new ones. Therefore, we need to
reset the transaction's read and commit timestamps back to default values `kMaxTxnTimestamp`.
Otherwise, `CommitAndTryCreateSnapshot()` may fail with "Status::InvalidArgument("Different commit ts specified")".

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10677

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D39513543

Pulled By: riversand963

fbshipit-source-id: bea01cac149bff3a23a2978fc0c3b198243a6291
2022-09-14 18:28:21 -07:00
Levi Tamasi 87c8bb4bef Add comments describing {Put,Get}Entity, update/clarify comment for Get and iterator (#10676)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/10676

Reviewed By: riversand963

Differential Revision: D39512081

Pulled By: ltamasi

fbshipit-source-id: 55704478ceb8081003eceeb0c5a3875cb806587e
2022-09-14 14:33:05 -07:00
anand76 bb9a6d4e4b Bypass a MultiGet test when async_io is used (#10669)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/10669

Reviewed By: akankshamahajan15

Differential Revision: D39492658

Pulled By: anand1976

fbshipit-source-id: abef79808e30762654680f7dd7e46487c631febc
2022-09-14 09:59:54 -07:00
anand76 7b11d48444 Change MultiGet multi-level optimization to default on (#10671)
Summary:
Change the ```ReadOptions.optimize_multiget_for_io``` flag to default on. It doesn't impact regular MultiGet users as its only applicable when ```ReadOptions.async_io``` is also set to true.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10671

Reviewed By: akankshamahajan15

Differential Revision: D39477439

Pulled By: anand1976

fbshipit-source-id: 47abcdbfa69f9bc60422ab68a238b232e085d4ba
2022-09-14 08:51:16 -07:00
Levi Tamasi 06ab0a8b40 Add wide-column support to iterators (#10670)
Summary:
The patch extends the iterator API with a new `columns` method which
can be used to retrieve all wide columns for the current key. Similarly to
the `Get` and `GetEntity` APIs, the classic `value` API returns the value
of the default (anonymous) column for wide-column entities, and `columns`
returns an entity with a single default column for plain old key-values.
(The goal here is to maintain the invariant that `value()` is the same as
the value of the default column in `columns()`.) The patch also involves a
smaller refactoring: historically, `value()` was implemented using a bunch
of conditions, that is, the `Slice` to be returned was decided based on the
direction of the iteration, whether a merge had been done etc. when the
method was called; with the patch, the value to be exposed is stored in a
member `Slice value_` when the iterator lands on a new key, and `value()`
simply returns this `Slice`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10670

Test Plan: Ran `make check` and a simple blackbox crash test.

Reviewed By: riversand963

Differential Revision: D39475551

Pulled By: ltamasi

fbshipit-source-id: 29e7a6ed9ef340841aab36803b832b7c8f668b0b
2022-09-13 21:01:36 -07:00
Changyu Bi f291eefb02 Cache fragmented range tombstone list for mutable memtables (#10547)
Summary:
Each read from memtable used to read and fragment all the range tombstones into a `FragmentedRangeTombstoneList`. https://github.com/facebook/rocksdb/issues/10380 improved the inefficient here by caching a `FragmentedRangeTombstoneList` with each immutable memtable. This PR extends the caching to mutable memtables. The fragmented range tombstone can be constructed in either read (This PR) or write path (https://github.com/facebook/rocksdb/issues/10584). With both implementation, each `DeleteRange()` will invalidate the cache, and the difference is where the cache is re-constructed.`CoreLocalArray` is used to store the cache with each memtable so that multi-threaded reads can be efficient. More specifically, each core will have a shared_ptr to a shared_ptr pointing to the current cache. Each read thread will only update the reference count in its core-local shared_ptr, and this is only needed when reading from mutable memtables.

The choice between write path and read path is not an easy one: they are both improvement compared to no caching in the current implementation, but they favor different operations and could cause regression in the other operation (read vs write). The write path caching in (https://github.com/facebook/rocksdb/issues/10584) leads to a cleaner implementation, but I chose the read path caching here to avoid significant regression in write performance when there is a considerable amount of range tombstones in a single memtable (the number from the benchmark below suggests >1000 with concurrent writers). Note that even though the fragmented range tombstone list is only constructed in `DeleteRange()` operations, it could block other writes from proceeding, and hence affects overall write performance.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10547

Test Plan:
- TestGet() in stress test is updated in https://github.com/facebook/rocksdb/issues/10553 to compare Get() result against expected state: `./db_stress_branch --readpercent=57 --prefixpercent=4 --writepercent=25 -delpercent=5 --iterpercent=5 --delrangepercent=4`
- Perf benchmark: tested read and write performance where a memtable has 0, 1, 10, 100 and 1000 range tombstones.
```
./db_bench --benchmarks=fillrandom,readrandom --writes_per_range_tombstone=200 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=200000 --reads=100000 --disable_auto_compactions --max_num_range_tombstones=1000
```
Write perf regressed since the cost of constructing fragmented range tombstone list is shifted from every read to a single write. 6cbe5d8e172dc5f1ef65c9d0a6eedbd9987b2c72 is included in the last column as a reference to see performance impact on multi-thread reads if `CoreLocalArray` is not used.

micros/op averaged over 5 runs: first 4 columns are for fillrandom, last 4 columns are for readrandom.
|   |fillrandom main           | write path caching          | read path caching          |memtable V3 (https://github.com/facebook/rocksdb/issues/10308)     | readrandom main            | write path caching           | read path caching            |memtable V3      |
|---   |---  |---   |---   |---   | ---   |           ---   |  ---   |  ---   |
| 0                    |6.35                           |6.15                           |5.82                           |6.12                           |2.24                           |2.26                           |2.03                           |2.07                           |
| 1                    |5.99                           |5.88                           |5.77                           |6.28                           |2.65                           |2.27                           |2.24                           |2.5                            |
| 10                   |6.15                           |6.02                           |5.92                           |5.95                           |5.15                           |2.61                           |2.31                           |2.53                           |
| 100                  |5.95                           |5.78                           |5.88                           |6.23                           |28.31                          |2.34                           |2.45                           |2.94                           |
| 100 25 threads       |52.01                          |45.85                          |46.18                          |47.52                          |35.97                          |3.34                           |3.34                           |3.56                           |
| 1000                 |6.0                            |7.07                           |5.98                           |6.08                           |333.18                         |2.86                           |2.7                            |3.6                            |
| 1000 25 threads      |52.6                           |148.86                         |79.06                          |45.52                          |473.49                         |3.66                           |3.48                           |4.38                           |

  - Benchmark performance of`readwhilewriting` from https://github.com/facebook/rocksdb/issues/10552, 100 range tombstones are written: `./db_bench --benchmarks=readwhilewriting --writes_per_range_tombstone=500 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=100000 --reads=500000 --disable_auto_compactions --max_num_range_tombstones=10000 --finish_after_writes`

readrandom micros/op:
|  |main            |write path caching           |read path caching            |memtable V3      |
|---|---|---|---|---|
| single thread        |48.28                          |1.55                           |1.52                           |1.96                           |
| 25 threads           |64.3                           |2.55                           |2.67                           |2.64                           |

Reviewed By: ajkr

Differential Revision: D38895410

Pulled By: cbi42

fbshipit-source-id: 930bfc309dd1b2f4e8e9042f5126785bba577559
2022-09-13 20:07:28 -07:00
Akanksha Mahajan 03fc43976d Async optimization in scan path (#10602)
Summary:
Optimizations
1. In FilePrefetchBuffer, when data is overlapping between two buffers, it copies the data from first to third buffer, then from
second to third buffer to return continuous buffer. This optimization will call ReadAsync on first buffer as soon as buffer is empty instead of getting blocked by second buffer to copy the data.
2. For fixed size readahead_size, FilePrefetchBuffer will issues two async read calls. One with length + readahead_size_/2 on first buffer(if buffer is empty) and readahead_size_/2 on second buffer during seek.

- Add readahead_size to db_stress for stress testing these changes in https://github.com/facebook/rocksdb/pull/10632

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10602

Test Plan:
- CircleCI tests
- stress_test completed successfully
export CRASH_TEST_EXT_ARGS="--async_io=1"
make crash_test -j32
- db_bench showed no regression
   With this PR:
```
 ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=false -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=1
Set seed to 1661876074584472 because --seed was 0
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
Integrated BlobDB: blob cache disabled
RocksDB:    version 7.7.0
Date:       Tue Aug 30 09:14:34 2022
CPU:        32 * Intel Xeon Processor (Skylake)
CPUCache:   16384 KB
Keys:       32 bytes each (+ 0 bytes user-defined timestamp)
Values:     512 bytes each (256 bytes after compression)
Entries:    50000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    25939.9 MB (estimated)
FileSize:   13732.9 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: Snappy
Compression sampling rate: 0
Memtablerep: SkipListFactory
Perf Level: 1
------------------------------------------------
DB path: [/tmp/prefix_scan_prefetch_main1]
seekrandom   :  270878.018 micros/op 3 ops/sec 30.068 seconds 111 operations;  618.7 MB/s (111 of 111 found)

 ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=true -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=1
Set seed to 1661875332862922 because --seed was 0
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
Integrated BlobDB: blob cache disabled
RocksDB:    version 7.7.0
Date:       Tue Aug 30 09:02:12 2022
CPU:        32 * Intel Xeon Processor (Skylake)
CPUCache:   16384 KB
Keys:       32 bytes each (+ 0 bytes user-defined timestamp)
Values:     512 bytes each (256 bytes after compression)
Entries:    50000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    25939.9 MB (estimated)
FileSize:   13732.9 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: Snappy
Compression sampling rate: 0
Memtablerep: SkipListFactory
Perf Level: 1
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
DB path: [/tmp/prefix_scan_prefetch_main1]
seekrandom   :  358352.488 micros/op 2 ops/sec 30.102 seconds 84 operations;  474.4 MB/s (84 of 84 found)
```

Without PR in main:
```
./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=false -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=1
Set seed to 1661876425983045 because --seed was 0
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
Integrated BlobDB: blob cache disabled
RocksDB:    version 7.7.0
Date:       Tue Aug 30 09:20:26 2022
CPU:        32 * Intel Xeon Processor (Skylake)
CPUCache:   16384 KB
Keys:       32 bytes each (+ 0 bytes user-defined timestamp)
Values:     512 bytes each (256 bytes after compression)
Entries:    50000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    25939.9 MB (estimated)
FileSize:   13732.9 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: Snappy
Compression sampling rate: 0
Memtablerep: SkipListFactory
Perf Level: 1
------------------------------------------------
DB path: [/tmp/prefix_scan_prefetch_main1]
seekrandom   :  280881.953 micros/op 3 ops/sec 30.054 seconds 107 operations;  605.2 MB/s (107 of 107 found)

 ./db_bench -use_existing_db=true -db=/tmp/prefix_scan_prefetch_main1 -benchmarks="seekrandom" -key_size=32 -value_size=512 -num=50000000 -use_direct_reads=false -seek_nexts=327680 -duration=30 -ops_between_duration_checks=1 -async_io=0
Set seed to 1661876475267771 because --seed was 0
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
Integrated BlobDB: blob cache disabled
RocksDB:    version 7.7.0
Date:       Tue Aug 30 09:21:15 2022
CPU:        32 * Intel Xeon Processor (Skylake)
CPUCache:   16384 KB
Keys:       32 bytes each (+ 0 bytes user-defined timestamp)
Values:     512 bytes each (256 bytes after compression)
Entries:    50000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    25939.9 MB (estimated)
FileSize:   13732.9 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: Snappy
Compression sampling rate: 0
Memtablerep: SkipListFactory
Perf Level: 1
------------------------------------------------
DB path: [/tmp/prefix_scan_prefetch_main1]
seekrandom   :  363155.084 micros/op 2 ops/sec 30.142 seconds 83 operations;  468.1 MB/s (83 of 83 found)
```

Reviewed By: anand1976

Differential Revision: D39141328

Pulled By: akankshamahajan15

fbshipit-source-id: 560655922c1a437a8569c228abb31b8c0b413120
2022-09-12 17:42:01 -07:00
Andrew Kryczka 03c4ea26bb db_stress option to preserve all files until verification success (#10659)
Summary:
In `db_stress`, DB and expected state files containing changes leading up to a verification failure are often deleted, which makes debugging such failures difficult. On the DB side, flushed WAL files and compacted SST files are marked obsolete and then deleted. Without those files, we cannot pinpoint where a key that failed verification changed unexpectedly. On the expected state side, files for verifying prefix-recoverability in the presence of unsynced data loss are deleted before verification. These include a baseline state file containing the expected state at the time of the last successful verification, and a trace file containing all operations since then. Without those files, we cannot know the sequence of DB operations expected to be recovered.

This PR attempts to address this gap with a new `db_stress` flag: `preserve_unverified_changes`. Setting `preserve_unverified_changes=1` has two effects.

First, prior to startup verification, `db_stress` hardlinks all DB and expected state files in "unverified/" subdirectories of `FLAGS_db` and `FLAGS_expected_values_dir`. The separate directories are needed because the pre-verification opening process deletes files written by the previous `db_stress` run as described above. These "unverified/" subdirectories are cleaned up following startup verification success.

I considered other approaches for preserving DB files through startup verification, like using a read-only DB or preventing deletion of DB files externally, e.g., in the `Env` layer. However, I decided against it since such an approach would not work for expected state files, and I did not want to change the DB management logic. If there were a way to disable DB file deletions before regular DB open, I would have preferred to use that.

Second, `db_stress` attempts to keep all DB and expected state files that were live at some point since the start of the `db_stress` run. This is a bit tricky and involves the following changes.

- Open the DB with `disable_auto_compactions=1` and `avoid_flush_during_recovery=1`
- DisableFileDeletions()
- EnableAutoCompactions()

For this part, too, I would have preferred to use a hypothetical API that disables DB file deletion before regular DB open.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10659

Reviewed By: hx235

Differential Revision: D39407454

Pulled By: ajkr

fbshipit-source-id: 6e981025c7dce147649d2e770728471395a7fa53
2022-09-12 14:49:38 -07:00
Akanksha Mahajan bd2ad2f9a0 Fix stress test failure for async_io (#10660)
Summary:
Sanitize initial_auto_readahead_size if its greater than max_auto_readahead_size in case of async_io

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10660

Test Plan: Ran db_stress with intitial_auto_readahead_size  greater than max_auto_readahead_size.

Reviewed By: anand1976

Differential Revision: D39408095

Pulled By: akankshamahajan15

fbshipit-source-id: 07f933242f636cfbc7ccf042e0c8b959a8ec5f3a
2022-09-12 14:48:06 -07:00
Hui Xiao f79b3d19a7 Inject spurious wakeup and sleep before acquiring db mutex to expose race condition (#10291)
Summary:
**Context/Summary:**
Previous experience with bugs and flaky tests taught us there exist features in RocksDB vulnerable to race condition caused by acquiring db mutex at a particular timing. This PR aggressively exposes those vulnerable features by injecting spurious wakeup and sleep to cause acquiring db mutex at various timing in order to expose such race condition

**Testing:**
- `COERCE_CONTEXT_SWITCH=1 make -j56 check / make -j56 db_stress` should reveal
    - flaky tests caused by db mutex related race condition
       - Reverted https://github.com/facebook/rocksdb/pull/9528
       - A/B testing on `COMPILE_WITH_TSAN=1 make -j56 listener_test` w/ and w/o `COERCE_CONTEXT_SWITCH=1` followed by `./listener_test --gtest_filter=EventListenerTest.MultiCF --gtest_repeat=10`
       - `COERCE_CONTEXT_SWITCH=1` can cause expected test failure (i.e, expose target TSAN data race error) within 10 run while the other couldn't.
       - This proves our injection can expose flaky tests caused by db mutex related race condition faster.
    -  known or new race-condition-type of internal bug by continuously running this PR
- Performance
   - High ops-threads time: COERCE_CONTEXT_SWITCH=1 regressed by 4 times slower (2:01.16 vs 0:22.10 elapsed ). This PR will be run as a separate CI job so this regression won't affect any existing job.
```
TEST_TMPDIR=$db /usr/bin/time ./db_stress \
--ops_per_thread=100000 --expected_values_dir=$exp --clear_column_family_one_in=0 \
--write_buffer_size=524288 —target_file_size_base=524288 —ingest_external_file_one_in=100 —compact_files_one_in=1000 —compact_range_one_in=1000
```
  - Start-up time:  COERCE_CONTEXT_SWITCH=1 didn't regress by 25% (0:01.51 vs 0:01.29 elapsed)
```
TEST_TMPDIR=$db ./db_stress -ops_per_thread=100000000 -expected_values_dir=$exp --clear_column_family_one_in=0 & sleep 120; pkill -9 db_stress

TEST_TMPDIR=$db /usr/bin/time ./db_stress \
--ops_per_thread=1 -reopen=0 --expected_values_dir=$exp --clear_column_family_one_in=0 --destroy_db_initially=0
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10291

Reviewed By: ajkr

Differential Revision: D39231182

Pulled By: hx235

fbshipit-source-id: 7ab6695430460e0826727fd8c66679b32b3e44b6
2022-09-12 13:55:23 -07:00
anand76 be09943fb5 Build and link libfolly with RocksDB (#10103)
Summary:
The current integration with folly requires cherry-picking folly source files to include in RocksDB for external CI builds. Its not scaleable as we depend on more features in folly, such as coroutines. This PR adds a dependency from RocksDB to the folly library when ```USE_FOLLY``` or ```USE_COROUTINES``` are set. We build folly using the build scripts in ```third-party/folly```, relying on it to download and build its dependencies. A new ```Makefile``` target, ```build_folly```, is provided to make building folly easier.

A new option, ```USE_FOLLY_LITE``` is added to retain the old model of compiling selected folly sources with RocksDB. This might be useful for short-term development.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10103

Reviewed By: pdillinger

Differential Revision: D38426787

Pulled By: anand1976

fbshipit-source-id: 33bc84abd9fdc7e2567749f02aa1b2494eb62b2f
2022-09-11 21:40:11 -07:00
Akanksha Mahajan 7a9ecdac3c Add auto prefetching parameters to db_bench and db_stress (#10632)
Summary:
Same as title

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10632

Test Plan: make crash_test -j32

Reviewed By: anand1976

Differential Revision: D39241479

Pulled By: akankshamahajan15

fbshipit-source-id: 5db5b0c007da786bacc1b30d8926d36d6d029b87
2022-09-09 12:52:27 -07:00
ltamasi dc7d155438 Mention some recent blob caching related changes in HISTORY.md (#10653)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/10653

Reviewed By: riversand963

Differential Revision: D39368165

Pulled By: ltamasi

fbshipit-source-id: 06cfd3c87ca90b9d07c082d5e307c0dc6a16840c
2022-09-09 09:56:10 -07:00
Andrew Kryczka 4100eb3053 minor cleanups to db_crashtest.py (#10654)
Summary:
Expanded `all_params` to include all parameters crash test may set. Previously, `atomic_flush` was not included in `all_params` and thus was not visible to `finalize_and_sanitize()`. The consequence was manual crash test runs could provide unsafe combinations of parameters to `db_stress`. For example, running `db_crashtest.py` with `-atomic_flush=0` could cause `db_stress` to run with `-atomic_flush=0 -disable_wal=1`, which is known to produce inconsistencies across column families.

While expanding `all_params`, I found we cannot have an entry in it for both `db_stress` and `db_crashtest.py`. So I renamed `enable_tiered_storage` to `test_tiered_storage` for `db_crashtest.py`, which appears more conventional anyways.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10654

Reviewed By: hx235

Differential Revision: D39369349

Pulled By: ajkr

fbshipit-source-id: 31d9010c760c868b20d5e9bd78ba75c8ff3ce348
2022-09-08 17:39:22 -07:00
gitbw95 0148c4934d Add PerfContext counters for CompressedSecondaryCache (#10650)
Summary:
Add PerfContext counters for CompressedSecondaryCache.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10650

Test Plan: Unit Tests.

Reviewed By: anand1976

Differential Revision: D39354712

Pulled By: gitbw95

fbshipit-source-id: 1b90d3df99d08ddecd351edfd48d1e3723fdbc15
2022-09-08 16:35:57 -07:00
Yanqin Jin 3d67d79154 Fix overlapping check by excluding timestamp (#10615)
Summary:
With user-defined timestamp, checking overlapping should exclude
timestamp part from key. This has already been done for range checking
for files in sstableKeyCompare(), but not yet done when checking with
concurrent compactions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10615

Test Plan:
(Will add more tests)

make check
(Repro seems easier with this commit sha: git checkout 78bbdef530)
rm -rf /dev/shm/rocksdb/* &&
mkdir /dev/shm/rocksdb/rocksdb_crashtest_expected &&
./db_stress
--allow_data_in_errors=True --clear_column_family_one_in=0
--continuous_verification_interval=0 --data_block_index_type=1
--db=/dev/shm/rocksdb//rocksdb_crashtest_blackbox --delpercent=5
--delrangepercent=0
--expected_values_dir=/dev/shm/rocksdb//rocksdb_crashtest_expected
--iterpercent=0 --max_background_compactions=20
--max_bytes_for_level_base=10485760 --max_key=25000000
--max_write_batch_group_size_bytes=1048576 --nooverwritepercent=1
--ops_per_thread=1000000 --paranoid_file_checks=1 --partition_filters=0
--prefix_size=8 --prefixpercent=5 --readpercent=30 --reopen=0
--snapshot_hold_ops=100000 --subcompactions=1 --compaction_pri=3
--target_file_size_base=65536 --target_file_size_multiplier=2
--test_batches_snapshots=0 --test_cf_consistency=0 --use_multiget=1
--user_timestamp_size=8 --value_size_mult=32 --verify_checksum=1
--write_buffer_size=65536 --writepercent=60 -disable_wal=1

Reviewed By: akankshamahajan15

Differential Revision: D39146797

Pulled By: riversand963

fbshipit-source-id: 7fca800026ca6219220100b8b6cf84d907828163
2022-09-08 13:03:07 -07:00
Levi Tamasi fe56cb9aa0 Eliminate some allocations/copies around the blob cache (#10647)
Summary:
Historically, `BlobFileReader` has returned the blob(s) read from the file
in the `PinnableSlice` provided by the client. This interface was
preserved when caching was implemented for blobs, which meant that
the blob data was copied multiple times when caching was in use: first,
into the client-provided `PinnableSlice` (by `BlobFileReader::SaveValue`),
and then, into the object stored in the cache (by `BlobSource::PutBlobIntoCache`).
The patch eliminates these copies and the related allocations by changing
`BlobFileReader` so it returns its results in the form of heap-allocated `BlobContents`
objects that can be directly inserted into the cache. The allocations backing
these `BlobContents` objects are made using the blob cache's allocator if the
blobs are to be inserted into the cache (i.e. if a cache is configured and the
`fill_cache` read option is set). Note: this PR focuses on the common case when
blobs are compressed; some further small optimizations are possible for uncompressed
blobs.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10647

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D39335185

Pulled By: ltamasi

fbshipit-source-id: 464503d60a5520d654c8273ffb8efd5d1bcd7b36
2022-09-08 12:40:18 -07:00
Peter Dillinger 6de7081cf3 Always verify SST unique IDs on SST file open (#10532)
Summary:
Although we've been tracking SST unique IDs in the DB manifest
unconditionally, checking has been opt-in and with an extra pass at DB::Open
time. This changes the behavior of `verify_sst_unique_id_in_manifest` to
check unique ID against manifest every time an SST file is opened through
table cache (normal DB operations), replacing the explicit pass over files
at DB::Open time. This change also enables the option by default and
removes the "EXPERIMENTAL" designation.

One possible criticism is that the option no longer ensures the integrity
of a DB at Open time. This is far from an all-or-nothing issue. Verifying
the IDs of all SST files hardly ensures all the data in the DB is readable.
(VerifyChecksum is supposed to do that.) Also, with
max_open_files=-1 (default, extremely common), all SST files are
opened at DB::Open time anyway.

Implementation details:
* `VerifySstUniqueIdInManifest()` functions are the extra/explicit pass
that is now removed.
* Unit tests that manipulate/corrupt table properties have to opt out of
this check, because that corrupts the "actual" unique id. (And even for
testing we don't currently have a mechanism to set "no unique id"
in the in-memory file metadata for new files.)
* A lot of other unit test churn relates to (a) default checking on, and
(b) checking on SST open even without DB::Open (e.g. on flush)
* Use `FileMetaData` for more `TableCache` operations (in place of
`FileDescriptor`) so that we have access to the unique_id whenever
we might need to open an SST file. **There is the possibility of
performance impact because we can no longer use the more
localized `fd` part of an `FdWithKeyRange` but instead follow the
`file_metadata` pointer. However, this change (possible regression)
is only done for `GetMemoryUsageByTableReaders`.**
* Removed a completely unnecessary constructor overload of
`TableReaderOptions`

Possible follow-up:
* Verification only happens when opening through table cache. Are there
more places where this should happen?
* Improve error message when there is a file size mismatch vs. manifest
(FIXME added in the appropriate place).
* I'm not sure there's a justification for `FileDescriptor` to be distinct from
`FileMetaData`.
* I'm skeptical that `FdWithKeyRange` really still makes sense for
optimizing some data locality by duplicating some data in memory, but I
could be wrong.
* An unnecessary overload of NewTableReader was recently added, in
the public API nonetheless (though unusable there). It should be cleaned
up to put most things under `TableReaderOptions`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10532

Test Plan:
updated unit tests

Performance test showing no significant difference (just noise I think):
`./db_bench -benchmarks=readwhilewriting[-X10] -num=3000000 -disable_wal=1 -bloom_bits=8 -write_buffer_size=1000000 -target_file_size_base=1000000`
Before: readwhilewriting [AVG 10 runs] : 68702 (± 6932) ops/sec
After: readwhilewriting [AVG 10 runs] : 68239 (± 7198) ops/sec

Reviewed By: jay-zhuang

Differential Revision: D38765551

Pulled By: pdillinger

fbshipit-source-id: a827a708155f12344ab2a5c16e7701c7636da4c2
2022-09-07 22:52:42 -07:00
Bo Wang d490bfcdb6 Avoid recompressing cold block in CompressedSecondaryCache (#10527)
Summary:
**Summary:**
When a block is firstly `Lookup` from the secondary cache, we just insert a dummy block in the primary cache (charging the actual size of the block) and don’t erase the block from the secondary cache. A standalone handle is returned from `Lookup`. Only if the block is hit again, we erase it from the secondary cache and add it into the primary cache.

When a block is firstly evicted from the primary cache to the secondary cache, we just insert a dummy block (size 0) in the secondary cache. When the block is evicted again, it is treated as a hot block and is inserted into the secondary cache.

**Implementation Details**
Add a new state of LRUHandle: The handle is never inserted into the LRUCache (both hash table and LRU list) and it doesn't experience the above three states. The entry can be freed when refs becomes 0.  (refs >= 1 && in_cache == false && IS_STANDALONE == true)

The behaviors of  `LRUCacheShard::Lookup()` are updated if the secondary_cache is CompressedSecondaryCache:
1. If a handle is found in primary cache:
  1.1. If the handle's value is not nullptr, it is returned immediately.
  1.2. If the handle's value is nullptr, this means the handle is a dummy one. For a dummy handle, if it was retrieved from secondary cache, it may still exist in secondary cache.
    - 1.2.1. If no valid handle can be `Lookup` from secondary cache, return nullptr.
    - 1.2.2. If the handle from secondary cache is valid, erase it from the secondary cache and add it into the primary cache.
2. If a handle is not found in primary cache:
  2.1. If no valid handle can be `Lookup` from secondary cache, return nullptr.
  2.2.  If the handle from secondary cache is valid, insert a dummy block in the primary cache (charging the actual size of the block)  and return a standalone handle.

The behaviors of `LRUCacheShard::Promote()` are updated as follows:
1. If `e->sec_handle` has value, one of the following steps can happen:
  1.1. Insert a dummy handle and return a standalone handle to caller when `secondary_cache_` is `CompressedSecondaryCache` and e is a standalone handle.
  1.2. Insert the item into the primary cache and return the handle to caller.
  1.3. Exception handling.
3. If `e->sec_handle` has no value, mark the item as not in cache and charge the cache as its only metadata that'll shortly be released.

The behavior of  `CompressedSecondaryCache::Insert()` is updated:
1. If a block is evicted from the primary cache for the first time, a dummy item is inserted.
4. If a dummy item is found for a block, the block is inserted into the secondary cache.

The behavior of  `CompressedSecondaryCache:::Lookup()` is updated:
1. If a handle is not found or it is a dummy item, a nullptr is returned.
2. If `erase_handle` is true, the handle is erased.

The behaviors of  `LRUCacheShard::Release()` are adjusted for the standalone handles.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10527

Test Plan:
1. stress tests.
5. unit tests.
6. CPU profiling for db_bench.

Reviewed By: siying

Differential Revision: D38747613

Pulled By: gitbw95

fbshipit-source-id: 74a1eba7e1957c9affb2bd2ae3e0194584fa6eca
2022-09-07 19:00:27 -07:00
Levi Tamasi c8543296ca Support custom allocators for the blob cache (#10628)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/10628

Test Plan: `make check`

Reviewed By: akankshamahajan15

Differential Revision: D39228165

Pulled By: ltamasi

fbshipit-source-id: 591fdff08db400b170b26f0165551f86d33c1dbf
2022-09-06 13:31:48 -07:00
Andrew Kryczka 5a97e6b1d2 Deflake blob caching tests (#10636)
Summary:
Example failure:

```
db/blob/db_blob_basic_test.cc:226: Failure
Expected equality of these values:
  i
    Which is: 1
  num_blobs
    Which is: 5
```

I can't repro locally, but it looks like the 2KB cache is too small to guarantee no eviction happens between loading all the data into cache and reading from `kBlockCacheTier`. This 2KB setting appears to have come from a test where the cached entries are pinned, where it makes sense to have a small setting. However, such a small setting makes less sense when the blocks are evictable but must remain cached per the test's expectation. This PR increases the capacity setting to 2MB for those cases.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10636

Reviewed By: cbi42

Differential Revision: D39250976

Pulled By: ajkr

fbshipit-source-id: 769309f9a19cfac20b67b927805c8df5c1d2d1f5
2022-09-06 13:01:05 -07:00