Summary:
**Context/Summary:**
- Similar to https://github.com/facebook/rocksdb/pull/11288 but for user read such as `Get(), MultiGet(), DBIterator::XXX(), Verify(File)Checksum()`.
- For this, I refactored some user-facing `MultiGet` calls in `TransactionBase` and various types of `DB` so that it does not call a user-facing `Get()` but `GetImpl()` for passing the `ReadOptions::io_activity` check (see PR conversation)
- New user read stats breakdown are guarded by `kExceptDetailedTimers` since measurement shows they have 4-5% regression to the upstream/main.
- Misc
- More refactoring: with https://github.com/facebook/rocksdb/pull/11288, we complete passing `ReadOptions/IOOptions` to FS level. So we can now replace the previously [added](https://github.com/facebook/rocksdb/pull/9424) `rate_limiter_priority` parameter in `RandomAccessFileReader`'s `Read/MultiRead/Prefetch()` with `IOOptions::rate_limiter_priority`
- Also, `ReadAsync()` call time is measured in `SST_READ_MICRO` now
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11444
Test Plan:
- CI fake db crash/stress test
- Microbenchmarking
**Build** `make clean && ROCKSDB_NO_FBCODE=1 DEBUG_LEVEL=0 make -jN db_basic_bench`
- google benchmark version: 604f6fd3f4
- db_basic_bench_base: upstream
- db_basic_bench_pr: db_basic_bench_base + this PR
- asyncread_db_basic_bench_base: upstream + [db basic bench patch for IteratorNext](https://github.com/facebook/rocksdb/compare/main...hx235:rocksdb:micro_bench_async_read)
- asyncread_db_basic_bench_pr: asyncread_db_basic_bench_base + this PR
**Test**
Get
```
TEST_TMPDIR=/dev/shm ./db_basic_bench_{null_stat|base|pr} --benchmark_filter=DBGet/comp_style:0/max_data:134217728/per_key_size:256/enable_statistics:1/negative_query:0/enable_filter:0/mmap:1/threads:1 --benchmark_repetitions=1000
```
Result
```
Coming soon
```
AsyncRead
```
TEST_TMPDIR=/dev/shm ./asyncread_db_basic_bench_{base|pr} --benchmark_filter=IteratorNext/comp_style:0/max_data:134217728/per_key_size:256/enable_statistics:1/async_io:1/include_detailed_timers:0 --benchmark_repetitions=1000 > syncread_db_basic_bench_{base|pr}.out
```
Result
```
Base:
1956,1956,1968,1977,1979,1986,1988,1988,1988,1990,1991,1991,1993,1993,1993,1993,1994,1996,1997,1997,1997,1998,1999,2001,2001,2002,2004,2007,2007,2008,
PR (2.3% regression, due to measuring `SST_READ_MICRO` that wasn't measured before):
1993,2014,2016,2022,2024,2027,2027,2028,2028,2030,2031,2031,2032,2032,2038,2039,2042,2044,2044,2047,2047,2047,2048,2049,2050,2052,2052,2052,2053,2053,
```
Reviewed By: ajkr
Differential Revision: D45918925
Pulled By: hx235
fbshipit-source-id: 58a54560d9ebeb3a59b6d807639692614dad058a
Summary:
Follow a couple best practices:
- Allowed Google benchmark to decide number of iterations. Previously we hardcoded a value, which circumvented benchmark's heuristic for iterating until the result is stable.
- Made each iteration do similar work. Previously, an iteration could do different work depending if the key was found in the first, second, third, or no L0 file.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11498
Test Plan: none as I am unable to prove it is better
Reviewed By: hx235
Differential Revision: D46339050
Pulled By: ajkr
fbshipit-source-id: fcfc6da4111c5b3ae86d79d908afc5f61f96675b
Summary:
Context:
This is the first PR for WaitForCompact() Implementation with WaitForCompactOptions. In this PR, we are introducing `Status WaitForCompact(const WaitForCompactOptions& wait_for_compact_options)` in the public API. This currently utilizes the existing internal `WaitForCompact()` implementation (with default abort_on_pause = false). `abort_on_pause` has been moved to `WaitForCompactOptions&`. In the later PRs, we will introduce the following two options in `WaitForCompactOptions`
1. `bool flush = false` by default - If true, flush before waiting for compactions to finish. Must be set to true to ensure no immediate compactions (except perhaps periodic compactions) after closing and re-opening the DB.
2. `bool close_db = false` by default - If true, will also close the DB upon compactions finishing.
1. struct `WaitForCompactOptions` added to options.h and `abort_on_pause` in the internal API moved to the option struct.
2. `Status WaitForCompact(const WaitForCompactOptions& wait_for_compact_options)` introduced in `db.h`
3. Changed the internal WaitForCompact() to `WaitForCompact(const WaitForCompactOptions& wait_for_compact_options)` and checks for the `abort_on_pause` inside the option.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11436
Test Plan:
Following tests added
- `DBCompactionTest::WaitForCompactWaitsOnCompactionToFinish`
- `DBCompactionTest::WaitForCompactAbortOnPauseAborted`
- `DBCompactionTest::WaitForCompactContinueAfterPauseNotAborted`
- `DBCompactionTest::WaitForCompactShutdownWhileWaiting`
- `TransactionTest::WaitForCompactAbortOnPause`
NOTE: `TransactionTest::WaitForCompactAbortOnPause` was added to use `StackableDB` to ensure the wrapper function is in place.
Reviewed By: pdillinger
Differential Revision: D45799659
Pulled By: jaykorean
fbshipit-source-id: b5b58f95957f2ab47d1221dee32a61d6cdc4685b
Summary:
Context:
In pull request https://github.com/facebook/rocksdb/issues/11436, we are introducing a new public API `waitForCompact(const WaitForCompactOptions& wait_for_compact_options)`. This API invokes the internal implementation `waitForCompact(bool wait_unscheduled=false)`. The unscheduled parameter indicates the compactions that are not yet scheduled but are required to process items in the queue.
In certain cases, we are unable to wait for compactions, such as during a shutdown or when background jobs are paused. It is important to return the appropriate status in these scenarios. For all other cases, we should wait for all compaction and flush jobs, including the unscheduled ones. The primary purpose of this new API is to wait until the system has resolved its compaction debt. Currently, the usage of `wait_unscheduled` is limited to test code.
This pull request eliminates the usage of wait_unscheduled. The internal `waitForCompact()` API now waits for unscheduled compactions unless the db is undergoing a shutdown. In the event of a shutdown, the API returns `Status::ShutdownInProgress()`.
Additionally, a new parameter, `abort_on_pause`, has been introduced with a default value of `false`. This parameter addresses the possibility of waiting indefinitely for unscheduled jobs if `PauseBackgroundWork()` was called before `waitForCompact()` is invoked. By setting `abort_on_pause` to `true`, the API will immediately return `Status::Aborted`.
Furthermore, all tests that previously called `waitForCompact(true)` have been fixed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11443
Test Plan:
Existing tests that involve a shutdown in progress:
- DBCompactionTest::CompactRangeShutdownWhileDelayed
- DBTestWithParam::PreShutdownMultipleCompaction
- DBTestWithParam::PreShutdownCompactionMiddle
Reviewed By: pdillinger
Differential Revision: D45923426
Pulled By: jaykorean
fbshipit-source-id: 7dc93fe6a6841a7d9d2d72866fa647090dba8eae
Summary:
**Context:**
The existing stat rocksdb.sst.read.micros does not reflect each of compaction and flush cases but aggregate them, which is not so helpful for us to understand IO read behavior of each of them.
**Summary**
- Update `StopWatch` and `RandomAccessFileReader` to record `rocksdb.sst.read.micros` and `rocksdb.file.{flush/compaction}.read.micros`
- Fixed the default histogram in `RandomAccessFileReader`
- New field `ReadOptions/IOOptions::io_activity`; Pass `ReadOptions` through paths under db open, flush and compaction to where we can prepare `IOOptions` and pass it to `RandomAccessFileReader`
- Use `thread_status_util` for assertion in `DbStressFSWrapper` for continuous testing on we are passing correct `io_activity` under db open, flush and compaction
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11288
Test Plan:
- **Stress test**
- **Db bench 1: rocksdb.sst.read.micros COUNT ≈ sum of rocksdb.file.read.flush.micros's and rocksdb.file.read.compaction.micros's.** (without blob)
- May not be exactly the same due to `HistogramStat::Add` only guarantees atomic not accuracy across threads.
```
./db_bench -db=/dev/shm/testdb/ -statistics=true -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -target_file_size_base=655 -disable_auto_compactions=false -compression_type=none -bloom_bits=3 (-use_plain_table=1 -prefix_size=10)
```
```
// BlockBasedTable
rocksdb.sst.read.micros P50 : 2.009374 P95 : 4.968548 P99 : 8.110362 P100 : 43.000000 COUNT : 40456 SUM : 114805
rocksdb.file.read.flush.micros P50 : 1.871841 P95 : 3.872407 P99 : 5.540541 P100 : 43.000000 COUNT : 2250 SUM : 6116
rocksdb.file.read.compaction.micros P50 : 2.023109 P95 : 5.029149 P99 : 8.196910 P100 : 26.000000 COUNT : 38206 SUM : 108689
// PlainTable
Does not apply
```
- **Db bench 2: performance**
**Read**
SETUP: db with 900 files
```
./db_bench -db=/dev/shm/testdb/ -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -disable_auto_compactions=true -target_file_size_base=655 -compression_type=none
```run till convergence
```
./db_bench -seed=1678564177044286 -use_existing_db=true -db=/dev/shm/testdb -benchmarks=readrandom[-X60] -statistics=true -num=1000000 -disable_auto_compactions=true -compression_type=none -bloom_bits=3
```
Pre-change
`readrandom [AVG 60 runs] : 21568 (± 248) ops/sec`
Post-change (no regression, -0.3%)
`readrandom [AVG 60 runs] : 21486 (± 236) ops/sec`
**Compaction/Flush**run till convergence
```
./db_bench -db=/dev/shm/testdb2/ -seed=1678564177044286 -benchmarks="fillseq[-X60]" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -disable_auto_compactions=false -target_file_size_base=655 -compression_type=none
rocksdb.sst.read.micros COUNT : 33820
rocksdb.sst.read.flush.micros COUNT : 1800
rocksdb.sst.read.compaction.micros COUNT : 32020
```
Pre-change
`fillseq [AVG 46 runs] : 1391 (± 214) ops/sec; 0.7 (± 0.1) MB/sec`
Post-change (no regression, ~-0.4%)
`fillseq [AVG 46 runs] : 1385 (± 216) ops/sec; 0.7 (± 0.1) MB/sec`
Reviewed By: ajkr
Differential Revision: D44007011
Pulled By: hx235
fbshipit-source-id: a54c89e4846dfc9a135389edf3f3eedfea257132
Summary:
This PR avoids allocations and copies for the result of `GetMergeOperands()` when the average operand size is at least 256 bytes and the total operands size is at least 32KB. The `GetMergeOperands()` already included `PinnableSlice` but was calling `PinSelf()` (i.e., allocating and copying) for each operand. When this optimization takes effect, we instead call `PinSlice()` to skip that allocation and copy. Resources are pinned in order for the `PinnableSlice` to point to valid memory even after `GetMergeOperands()` returns.
The pinned resources include a referenced `SuperVersion`, a `MergingContext`, and a `PinnedIteratorsManager`. They are bundled into a `GetMergeOperandsState`. We use `SharedCleanablePtr` to share that bundle among all `PinnableSlice`s populated by `GetMergeOperands()`. That way, the last `PinnableSlice` to be `Reset()` will cleanup the bundle, including unreferencing the `SuperVersion`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10458
Test Plan:
- new DB level test
- measured benefit/regression in a number of memtable scenarios
Setup command:
```
$ ./db_bench -benchmarks=mergerandom -merge_operator=StringAppendOperator -num=$num -writes=16384 -key_size=16 -value_size=$value_sz -compression_type=none -write_buffer_size=1048576000
```
Benchmark command:
```
./db_bench -threads=$threads -use_existing_db=true -avoid_flush_during_recovery=true -write_buffer_size=1048576000 -benchmarks=readrandomoperands -merge_operator=StringAppendOperator -num=$num -duration=10
```
Worst regression is when a key has many tiny operands:
- Parameters: num=1 (implying 16384 operands per key), value_sz=8, threads=1
- `GetMergeOperands()` latency increases 682 micros -> 800 micros (+17%)
The regression disappears into the noise (<1% difference) if we remove the `Reset()` loop and the size counting loop. The former is arguably needed regardless of this PR as the convention in `Get()` and `MultiGet()` is to `Reset()` the input `PinnableSlice`s at the start. The latter could be optimized to count the size as we accumulate operands rather than after the fact.
Best improvement is when a key has large operands and high concurrency:
- Parameters: num=4 (implying 4096 operands per key), value_sz=2KB, threads=32
- `GetMergeOperands()` latency decreases 11492 micros -> 437 micros (-96%).
Reviewed By: cbi42
Differential Revision: D38336578
Pulled By: ajkr
fbshipit-source-id: 48146d127e04cb7f2d4d2939a2b9dff3aba18258
Summary:
Iterator is not freed after test is done (after the main for
loop), which could cause db close failed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10058
Test Plan:
Able to reproduce consistently with higher thread number,
like 100, make sure it passes after the fix
Reviewed By: ajkr
Differential Revision: D36685823
Pulled By: jay-zhuang
fbshipit-source-id: 4c98b8758d106bfe40cae670e689c3d284765bcf
Summary:
The new microbenchmarks, DBGetMergeOperandsInMemtable and DBGetMergeOperandsInSstFile, correspond to the two different LSMs tested: all data in one memtable and all data in one SST file, respectively. Both cases are parameterized by thread count (1 or 8) and merge operands per key (1, 32, or 1024). The SST file case is additionally parameterized by whether data is in block cache or mmap'd memory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9971
Test Plan:
```
$ TEST_TMPDIR=/dev/shm/db_basic_bench/ ./db_basic_bench --benchmark_filter=DBGetMergeOperands
The number of inputs is very large. DBGet will be repeated at least 192 times.
The number of inputs is very large. DBGet will be repeated at least 192 times.
2022-05-09T13:15:40-07:00
Running ./db_basic_bench
Run on (36 X 2570.91 MHz CPU s)
CPU Caches:
L1 Data 32 KiB (x18)
L1 Instruction 32 KiB (x18)
L2 Unified 1024 KiB (x18)
L3 Unified 25344 KiB (x1)
Load Average: 4.50, 4.33, 4.37
----------------------------------------------------------------------------------------------------------------------------
Benchmark Time CPU Iterations UserCounters...
----------------------------------------------------------------------------------------------------------------------------
DBGetMergeOperandsInMemtable/entries_per_key:1/threads:1 846 ns 846 ns 849893 db_size=0
DBGetMergeOperandsInMemtable/entries_per_key:32/threads:1 2436 ns 2436 ns 305779 db_size=0
DBGetMergeOperandsInMemtable/entries_per_key:1024/threads:1 77226 ns 77224 ns 8152 db_size=0
DBGetMergeOperandsInMemtable/entries_per_key:1/threads:8 116 ns 929 ns 779368 db_size=0
DBGetMergeOperandsInMemtable/entries_per_key:32/threads:8 330 ns 2644 ns 280824 db_size=0
DBGetMergeOperandsInMemtable/entries_per_key:1024/threads:8 12466 ns 99718 ns 7200 db_size=0
DBGetMergeOperandsInSstFile/entries_per_key:1/mmap:0/threads:1 1640 ns 1640 ns 461262 db_size=21.7826M
DBGetMergeOperandsInSstFile/entries_per_key:1/mmap:1/threads:1 1693 ns 1693 ns 439936 db_size=21.7826M
DBGetMergeOperandsInSstFile/entries_per_key:32/mmap:0/threads:1 3999 ns 3999 ns 172881 db_size=19.6981M
DBGetMergeOperandsInSstFile/entries_per_key:32/mmap:1/threads:1 5544 ns 5543 ns 135657 db_size=19.6981M
DBGetMergeOperandsInSstFile/entries_per_key:1024/mmap:0/threads:1 78767 ns 78761 ns 8395 db_size=19.6389M
DBGetMergeOperandsInSstFile/entries_per_key:1024/mmap:1/threads:1 157242 ns 157238 ns 4495 db_size=19.6389M
DBGetMergeOperandsInSstFile/entries_per_key:1/mmap:0/threads:8 231 ns 1848 ns 347768 db_size=21.7826M
DBGetMergeOperandsInSstFile/entries_per_key:1/mmap:1/threads:8 214 ns 1715 ns 393312 db_size=21.7826M
DBGetMergeOperandsInSstFile/entries_per_key:32/mmap:0/threads:8 596 ns 4767 ns 142088 db_size=19.6981M
DBGetMergeOperandsInSstFile/entries_per_key:32/mmap:1/threads:8 720 ns 5757 ns 118200 db_size=19.6981M
DBGetMergeOperandsInSstFile/entries_per_key:1024/mmap:0/threads:8 11613 ns 92460 ns 7344 db_size=19.6389M
DBGetMergeOperandsInSstFile/entries_per_key:1024/mmap:1/threads:8 19989 ns 159908 ns 4440 db_size=19.6389M
```
Reviewed By: jay-zhuang
Differential Revision: D36258861
Pulled By: ajkr
fbshipit-source-id: 04b733e1cc3a4a70ed9baa894c50fdf96c0d6064
Summary:
ToString() is created as some platform doesn't support std::to_string(). However, we've already used std::to_string() by mistake for 16 months (in db/db_info_dumper.cc). This commit just remove ToString().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9955
Test Plan: Watch CI tests
Reviewed By: riversand963
Differential Revision: D36176799
fbshipit-source-id: bdb6dcd0e3a3ab96a1ac810f5d0188f684064471
Summary:
Use `unique_ptr<DB>` to make sure the DB object is deleted. Previously it was not, which led to accumulating file descriptors for deleted directories because a `DBImpl::db_dir_` from each test remained alive.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9939
Test Plan: run `lsof -p $(pidof db_basic_bench)` while benchmark runs; verify no FDs for deleted directories.
Reviewed By: jay-zhuang
Differential Revision: D36108761
Pulled By: ajkr
fbshipit-source-id: cfe02646b038a445af7d5db8989eb1f40d658359
Summary:
I tried evaluating https://github.com/facebook/rocksdb/issues/9611 using DBGet microbenchmarks but mostly found the change is well within the noise even for hundreds of repetitions; meanwhile, the InternalKeyComparator CPU it saves is 1-2% according to perf so it should be measurable. In this PR I tried adding a mmap mode that will bypass compression/checksum/block cache/file read to focus more on the block lookup paths, and also increased the Get() count.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9903
Reviewed By: jay-zhuang, riversand963
Differential Revision: D35907375
Pulled By: ajkr
fbshipit-source-id: 69490d5040ef0863e1ce296724104d0aa7667215
Summary:
This commit was generated using `mgt import`.
pristine code for third-party libraries:
third-party/benchmark
upgrade google benchmark to v1.6.1
contains a local patch that reverts [this](https://github.com/google/benchmark/pull/1227?fbclid=IwAR2CCmIJmjU62SPPQQf_t8kdAsMjYv_Pa_GxabYUOdQpGPZUHKwbnYS_1oE) and changs `enum Flags` to be `enum Flags : uint32_t`.
Reviewed By: chadaustin
Differential Revision: D35136540
fbshipit-source-id: f3662f953cd87956e5e9b767e55e3697f99d3b49
Summary:
DBGet p95 and p99 have high variation, remove them for now.
Also increase the iteration to 3 to avoid false positive.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9742
Test Plan: Internal CI
Reviewed By: ajkr
Differential Revision: D35082820
Pulled By: jay-zhuang
fbshipit-source-id: facc1d56b94e54aa8c8852c207aae2ae4e4924b0
Summary:
* Add more micro-benchmark tests
* Expose an API in DBImpl for waiting for compactions (still not visible to the user)
* Add argument name for ribbon_bench
* remove benchmark run from CI, as it runs too long.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9436
Test Plan: CI
Reviewed By: riversand963
Differential Revision: D33777836
Pulled By: jay-zhuang
fbshipit-source-id: c05de3bc082cc05b5d019f00b324e774bf4bbd96
Summary:
Directory fsync might be expensive on btrfs and it may not be needed.
Here are 4 directory fsync cases:
1. creating a new file: dir-fsync is not needed on btrfs, as long as the
new file itself is synced.
2. renaming a file: dir-fsync is not needed if the renamed file is
synced. So an API `FsyncAfterFileRename(filename, ...)` is provided
to sync the file on btrfs. By default, it just calls dir-fsync.
3. deleting files: dir-fsync is forced by set
`IOOptions.force_dir_fsync = true`
4. renaming multiple files (like backup and checkpoint): dir-fsync is
forced, the same as above.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8903
Test Plan: run tests on btrfs and non btrfs
Reviewed By: ajkr
Differential Revision: D30885059
Pulled By: jay-zhuang
fbshipit-source-id: dd2730b31580b0bcaedffc318a762d7dbf25de4a
Andrew Kryczka