Commit Graph

973 Commits

Author SHA1 Message Date
feilongliu
0b0cb6f1a2 Fix segfalut in ~DBWithTTLImpl() when called after Close() (#5485)
Summary:
~DBWithTTLImpl() fails after calling Close() function (will invoke the
Close() function of DBImpl), because the Close() function deletes
default_cf_handle_ which is used in the GetOptions() function called
in ~DBWithTTLImpl(), hence lead to segfault.

Fix by creating a Close() function for the DBWithTTLImpl class and do
the close and the work originally in ~DBWithTTLImpl(). If the Close()
function is not called, it will be called in the ~DBWithTTLImpl()
function.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5485

Test Plan: make clean;  USE_CLANG=1 make all check -j

Differential Revision: D15924498

fbshipit-source-id: 567397fb972961059083a1ae0f9f99ff74872b78
2019-06-20 13:08:17 -07:00
Vaibhav Gogte
f46a2a0375 Export Cache::GetCharge (#5476)
Summary:
Exporting GetCharge to cache.hh
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5476

Differential Revision: D15881882

Pulled By: riversand963

fbshipit-source-id: 3d99084d10059b4fcaaaba240606ed50bc23351c
2019-06-18 17:35:41 -07:00
haoyuhuang
2d1dd5bce7 Support computing miss ratio curves using sim_cache. (#5449)
Summary:
This PR adds a BlockCacheTraceSimulator that reports the miss ratios given different cache configurations. A cache configuration contains "cache_name,num_shard_bits,cache_capacities". For example, "lru, 1, 1K, 2K, 4M, 4G".

When we replay the trace, we also perform lookups and inserts on the simulated caches.
In the end, it reports the miss ratio for each tuple <cache_name, num_shard_bits, cache_capacity> in a output file.

This PR also adds a main source block_cache_trace_analyzer so that we can run the analyzer in command line.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5449

Test Plan:
Added tests for block_cache_trace_analyzer.
COMPILE_WITH_ASAN=1 make check -j32.

Differential Revision: D15797073

Pulled By: HaoyuHuang

fbshipit-source-id: aef0c5c2e7938f3e8b6a10d4a6a50e6928ecf408
2019-06-17 16:41:12 -07:00
Maysam Yabandeh
60f3ec2ca5 Fix appveyor compliant about passing const to thread (#5447)
Summary:
CLANG would complain if we pass const to lambda function and appveyor complains if we don't (https://github.com/facebook/rocksdb/pull/5443). The patch fixes that by using the default capture mode.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5447

Differential Revision: D15788722

Pulled By: maysamyabandeh

fbshipit-source-id: 47e7f49264afe31fdafe42cb8bf93da126abfca9
2019-06-12 15:06:22 -07:00
Maysam Yabandeh
4a285d0dd3 Remove passing const variable to thread (#5443)
Summary:
CLANG complains that passing const to thread is not necessary. The patch removes it form PreparedHeap::Concurrent test.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5443

Differential Revision: D15781598

Pulled By: maysamyabandeh

fbshipit-source-id: 3aceb05d96182fa4726d6d37eed45fd3aac4c016
2019-06-12 09:45:57 -07:00
Maysam Yabandeh
773f914a40 WritePrepared: switch PreparedHeap from priority_queue to deque (#5436)
Summary:
Internally PreparedHeap is currently using a priority_queue. The rationale was the in the initial design PreparedHeap::AddPrepared could be called in arbitrary order. With the recent optimizations, we call ::AddPrepared only from the main write queue, which results into in-order insertion into PreparedHeap. The patch thus replaces the underlying priority_queue with a more efficient deque implementation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5436

Differential Revision: D15752147

Pulled By: maysamyabandeh

fbshipit-source-id: e6960f2b2097e13137dded1ceeff3b10b03b0aeb
2019-06-11 19:55:14 -07:00
Manuel Ung
ca1aee2a19 WriteUnprepared: commit only from the 2nd queue (#5439)
Summary:
This is a port of this PR into WriteUnprepared:
https://github.com/facebook/rocksdb/pull/5014

This also reverts this test change to restore some flaky write unprepared
tests: https://github.com/facebook/rocksdb/pull/5315

Tested with:
$ gtest-parallel ./transaction_test --gtest_filter=MySQLStyleTransactionTest/MySQLStyleTransactionTest.TransactionStressTest/9 --repeat=128
[128/128] MySQLStyleTransactionTest/MySQLStyleTransactionTest.TransactionStressTest/9 (18250 ms)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5439

Differential Revision: D15761405

Pulled By: lth

fbshipit-source-id: ae2581fd942d8a5b3f9278fd6bc3c1ac0b2c964c
2019-06-11 18:01:39 -07:00
sdong
58c4aee42e TransactionUtil::CheckKey() to skip unnecessary history (#4941)
Summary:
If a memtable definitely covers a key, there isn't a need to check older memtables.
We can skip them by checking the earliest sequence number.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4941

Differential Revision: D13932666

fbshipit-source-id: b9d52f234b8ad9dd3bf6547645cd457175a3ca9b
2019-06-11 11:46:42 -07:00
Maysam Yabandeh
c292dc8540 WritePrepared: reduce prepared_mutex_ overhead (#5420)
Summary:
The patch reduces the contention over prepared_mutex_ using these techniques:
1) Move ::RemovePrepared() to be called from the commit callback when we have two write queues.
2) Use two separate mutex for PreparedHeap, one prepared_mutex_ needed for ::RemovePrepared, and one ::push_pop_mutex() needed for ::AddPrepared(). Given that we call ::AddPrepared only from the first write queue and ::RemovePrepared mostly from the 2nd, this will result into each the two write queues not competing with each other over a single mutex. ::RemovePrepared might occasionally need to acquire ::push_pop_mutex() if ::erase() ends up with calling ::pop()
3) Acquire ::push_pop_mutex() on the first callback of the write queue and release it on the last.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5420

Differential Revision: D15741985

Pulled By: maysamyabandeh

fbshipit-source-id: 84ce8016007e88bb6e10da5760ba1f0d26347735
2019-06-10 11:53:31 -07:00
Zhongyi Xie
d68f9f4580 simplify include directive involving inttypes (#5402)
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402

Differential Revision: D15701195

Pulled By: miasantreble

fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
2019-06-06 13:56:07 -07:00
Maysam Yabandeh
ae05a83e19 Call ValidateOptions from SetOptions (#5368)
Summary:
Currently we validate options in DB::Open. However the validation step is missing when options are dynamically updated in ::SetOptions. The patch fixes that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5368

Differential Revision: D15540101

Pulled By: maysamyabandeh

fbshipit-source-id: d27bbffd8f0252d1b50bcf59e0a70a278ed937f4
2019-06-03 19:49:57 -07:00
Siying Dong
5851cb7fdb Move util/trace_replay.* to trace_replay/ (#5376)
Summary:
util/ means for lower level libraries. trace_replay is highly integrated to DB and sometimes call DB. Move it out to a separate directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5376

Differential Revision: D15550938

Pulled By: siying

fbshipit-source-id: f46dce5ceffdc05a73f26379c7bb1b79ebe6c207
2019-06-03 13:25:26 -07:00
Siying Dong
000b9ec217 Move some logging related files to logging/ (#5387)
Summary:
Many logging related source files are under util/. It will be more structured if they are together.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5387

Differential Revision: D15579036

Pulled By: siying

fbshipit-source-id: 3850134ed50b8c0bb40a0c8ae1f184fa4081303f
2019-05-31 17:23:59 -07:00
Vijay Nadimpalli
cae22c53fb Make format
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5395

Differential Revision: D15581698

Pulled By: vjnadimpalli

fbshipit-source-id: f415972f16e784b1361714c202b97defcab46767
2019-05-31 15:24:43 -07:00
Vijay Nadimpalli
49c5a12dbe Organizing rocksdb/db directory
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5390

Differential Revision: D15579388

Pulled By: vjnadimpalli

fbshipit-source-id: 5bfc95e31554b8ff05b97b76d6534113f527f366
2019-05-31 11:57:01 -07:00
Siying Dong
cb094e13bb Auto roll logger to enforce options.keep_log_file_num immediately after a new file is created (#5370)
Summary:
Right now, with auto roll logger, options.keep_log_file_num enforcement is triggered by events like DB reopen or full obsolete scan happens. In the mean time, the size and number of log files can grow without a limit. We put a stronger enforcement to the option, so that the number of log files can always under control.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5370

Differential Revision: D15570413

Pulled By: siying

fbshipit-source-id: 0916c3c4d42ab8fdd29389ee7fd7e1557b03176e
2019-05-31 10:50:19 -07:00
Siying Dong
8843129ece Move some memory related files from util/ to memory/ (#5382)
Summary:
Move arena, allocator, and memory tools under util to a separate memory/ directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5382

Differential Revision: D15564655

Pulled By: siying

fbshipit-source-id: 9cd6b5d0d3d52b39606e19221fa154596e5852a5
2019-05-30 17:44:09 -07:00
Vijay Nadimpalli
50e470791d Organizing rocksdb/table directory by format
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5373

Differential Revision: D15559425

Pulled By: vjnadimpalli

fbshipit-source-id: 5d6d6d615582bedd96a4b879bb25d429a6de8b55
2019-05-30 14:51:11 -07:00
Siying Dong
e9e0101ca4 Move test related files under util/ to test_util/ (#5377)
Summary:
There are too many types of files under util/. Some test related files don't belong to there or just are just loosely related. Mo
ve them to a new directory test_util/, so that util/ is cleaner.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5377

Differential Revision: D15551366

Pulled By: siying

fbshipit-source-id: 0f5c8653832354ef8caa31749c0143815d719e2c
2019-05-30 11:25:51 -07:00
Siying Dong
545d206040 Move some file related files outside util/ (#5375)
Summary:
util/ means for lower level libraries, so it's a good idea to move the files which requires knowledge to DB out. Create a file/ and move some files there.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5375

Differential Revision: D15550935

Pulled By: siying

fbshipit-source-id: 61a9715dcde5386eebfb43e93f847bba1ae0d3f2
2019-05-29 20:47:06 -07:00
Maysam Yabandeh
eab4f49a2c WritePrepared: skip_concurrency_control option (#5330)
Summary:
This enables the user to set TransactionDBOptions::skip_concurrency_control so the standard `DB::Write(const WriteOptions& opts, WriteBatch* updates)` would skip the concurrency control. This would give higher throughput to the users who know their use case doesn't need concurrency control.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5330

Differential Revision: D15525932

Pulled By: maysamyabandeh

fbshipit-source-id: 68421ac1ba34f549a4a8de9ce4c2dccf6fb4b06b
2019-05-28 16:29:45 -07:00
Maysam Yabandeh
f5576c3317 WritePrepared: disableWAL in commit without prepare (#5327)
Summary:
When committing a transaction without prepare, WritePrepared simply writes the batch to db and add the commit entry to CommitCache. When two_write_queues=true, following the rule of committing only from 2nd write queue, the first write, writes the batch and the only thing the 2nd write does is to write the commit entry to CommitCache. Currently the write batch in 2nd write is set to an empty LogData entry, while the write to the WAL could simply be entirely disabled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5327

Differential Revision: D15424546

Pulled By: maysamyabandeh

fbshipit-source-id: 3d9ea3922d5196984c584d62a3ed57e1f7ca7b9f
2019-05-28 14:21:52 -07:00
Maysam Yabandeh
5c0e304170 WritePrepared: Clarify the need for two_write_queues in unordered_write (#5313)
Summary:
WritePrepared transactions when configured with two_write_queues=true offers higher throughput with unordered_write feature without however compromising the rocksdb guarantees. This is because it performs ordering among writes in a 2nd step that is not tied to memtable write speed. The 2nd step is naturally provided by 2PC when the commit phase does the ordering as well. Without 2PC, the 2nd step would only be provided when we use two_write_queues=true, where WritePrepared after performing the writes, in a 2nd step uses the 2nd queue to assign order to the writes.
The patch clarifies the need for two_write_queues=true in the HISTORY and inline comments of unordered_writes. Moreover it extends the stress tests of WritePrepared to unordred_write.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5313

Differential Revision: D15379977

Pulled By: maysamyabandeh

fbshipit-source-id: 5b6f05b9b59285dcbf3b0532215ba9fe7d926e00
2019-05-20 07:49:20 -07:00
Maysam Yabandeh
c71f5bb9aa Disable WriteUnPrepared stress tests (#5315)
Summary:
They are kind of flaky at the moment. Will re-enable it when flakiness is fixed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5315

Differential Revision: D15382744

Pulled By: maysamyabandeh

fbshipit-source-id: 8b2f9d81a4bb34bfd51481727a682d5cd063c5e3
2019-05-16 15:39:33 -07:00
Maysam Yabandeh
f0e8216197 WritePrepared: Fix deadlock in WriteRecoverableState (#5306)
Summary:
The recent improvement in https://github.com/facebook/rocksdb/pull/3661 could cause a deadlock: When writing recoverable state, we also commit its sequence number to commit table, which could result into evicting existing commit entry, which could result into advancing max_evicted_seq_, which would need to get snapshots from database, which requires obtaining db mutex. The patch releases db_mutex before calling the callback in WriteRecoverableState to avoid the potential deadlock. It also improves the stress tests to let the issue be manifested in the tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5306

Differential Revision: D15341458

Pulled By: maysamyabandeh

fbshipit-source-id: 05dcbed7e21b789fd1e5fd5ee8eea08077162323
2019-05-15 13:53:54 -07:00
Thomas Fersch
a42757607d Use pre-increment instead of post-increment for iterators (#5296)
Summary:
Google C++ style guide indicates pre-increment should be used for iterators: https://google.github.io/styleguide/cppguide.html#Preincrement_and_Predecrement. Replaced all instances of ' it++' by ' ++it' (where type is iterator). So this covers the cases where iterators are named 'it'.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5296

Differential Revision: D15301256

Pulled By: tfersch

fbshipit-source-id: 2803483c1392504ad3b281d21db615429c71114b
2019-05-15 13:19:15 -07:00
Maysam Yabandeh
f383641a1d Unordered Writes (#5218)
Summary:
Performing unordered writes in rocksdb when unordered_write option is set to true. When enabled the writes to memtable are done without joining any write thread. This offers much higher write throughput since the upcoming writes would not have to wait for the slowest memtable write to finish. The tradeoff is that the writes visible to a snapshot might change over time. If the application cannot tolerate that, it should implement its own mechanisms to work around that. Using TransactionDB with WRITE_PREPARED write policy is one way to achieve that. Doing so increases the max throughput by 2.2x without however compromising the snapshot guarantees.
The patch is prepared based on an original by siying
Existing unit tests are extended to include unordered_write option.

Benchmark Results:
```
TEST_TMPDIR=/dev/shm/ ./db_bench_unordered --benchmarks=fillrandom --threads=32 --num=10000000 -max_write_buffer_number=16 --max_background_jobs=64 --batch_size=8 --writes=3000000 -level0_file_num_compaction_trigger=99999 --level0_slowdown_writes_trigger=99999 --level0_stop_writes_trigger=99999 -enable_pipelined_write=false -disable_auto_compactions  --unordered_write=1
```
With WAL
- Vanilla RocksDB: 78.6 MB/s
- WRITER_PREPARED with unordered_write: 177.8 MB/s (2.2x)
- unordered_write: 368.9 MB/s (4.7x with relaxed snapshot guarantees)

Without WAL
- Vanilla RocksDB: 111.3 MB/s
- WRITER_PREPARED with unordered_write: 259.3 MB/s MB/s (2.3x)
- unordered_write: 645.6 MB/s (5.8x with relaxed snapshot guarantees)

- WRITER_PREPARED with unordered_write disable concurrency control: 185.3 MB/s MB/s (2.35x)

Limitations:
- The feature is not yet extended to `max_successive_merges` > 0. The feature is also incompatible with `enable_pipelined_write` = true as well as with `allow_concurrent_memtable_write` = false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5218

Differential Revision: D15219029

Pulled By: maysamyabandeh

fbshipit-source-id: 38f2abc4af8780148c6128acdba2b3227bc81759
2019-05-13 17:47:21 -07:00
anand76
1c8cbf315f Extend MultiGet batching to Transactions (#5210)
Summary:
MultiGet batching was implemented in #5011 in order to reduce CPU utilization when looking up multiple keys at once. This PR implements corresponding ```MultiGet``` and ```MultiGetSingleCFForUpdate``` in ```rocksdb::Transaction``` that call the underlying batching implementation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5210

Differential Revision: D15048164

Pulled By: anand1976

fbshipit-source-id: c52f6043102ab0cbc723f4cba2a7b7d1767f6f52
2019-04-23 14:11:26 -07:00
Andrew Kryczka
8272a6de57 Optionally wait on bytes_per_sync to smooth I/O (#5183)
Summary:
The existing implementation does not guarantee bytes reach disk every `bytes_per_sync` when writing SST files, or every `wal_bytes_per_sync` when writing WALs. This can cause confusing behavior for users who enable this feature to avoid large syncs during flush and compaction, but then end up hitting them anyways.

My understanding of the existing behavior is we used `sync_file_range` with `SYNC_FILE_RANGE_WRITE` to submit ranges for async writeback, such that we could continue processing the next range of bytes while that I/O is happening. I believe we can preserve that benefit while also limiting how far the processing can get ahead of the I/O, which prevents huge syncs from happening when the file finishes.

Consider this `sync_file_range` usage: `sync_file_range(fd_, 0, static_cast<off_t>(offset + nbytes), SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE)`. Expanding the range to start at 0 and adding the `SYNC_FILE_RANGE_WAIT_BEFORE` flag causes any pending writeback (like from a previous call to `sync_file_range`) to finish before it proceeds to submit the latest `nbytes` for writeback. The latest `nbytes` are still written back asynchronously, unless processing exceeds I/O speed, in which case the following `sync_file_range` will need to wait on it.

There is a second change in this PR to use `fdatasync` when `sync_file_range` is unavailable (determined statically) or has some known problem with the underlying filesystem (determined dynamically).

The above two changes only apply when the user enables a new option, `strict_bytes_per_sync`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5183

Differential Revision: D14953553

Pulled By: siying

fbshipit-source-id: 445c3862e019fb7b470f9c7f314fc231b62706e9
2019-04-22 11:51:39 -07:00
jsteemann
de76909464 refactor SavePoints (#5192)
Summary:
Savepoints are assumed to be used in a stack-wise fashion (only
the top element should be used), so they were stored by `WriteBatch`
in a member variable `save_points` using an std::stack.

Conceptually this is fine, but the implementation had a few issues:
- the `save_points_` instance variable was a plain pointer to a heap-
  allocated `SavePoints` struct. The destructor of `WriteBatch` simply
  deletes this pointer. However, the copy constructor of WriteBatch
  just copied that pointer, meaning that copying a WriteBatch with
  active savepoints will very likely have crashed before. Now a proper
  copy of the savepoints is made in the copy constructor, and not just
  a copy of the pointer
- `save_points_` was an std::stack, which defaults to `std::deque` for
  the underlying container. A deque is a bit over the top here, as we
  only need access to the most recent savepoint (i.e. stack.top()) but
  never any elements at the front. std::deque is rather expensive to
  initialize in common environments. For example, the STL implementation
  shipped with GNU g++ will perform a heap allocation of more than 500
  bytes to create an empty deque object. Although the `save_points_`
  container is created lazily by RocksDB, moving from a deque to a plain
  `std::vector` is much more memory-efficient. So `save_points_` is now
  a vector.
- `save_points_` was changed from a plain pointer to an `std::unique_ptr`,
  making ownership more explicit.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5192

Differential Revision: D15024074

Pulled By: maysamyabandeh

fbshipit-source-id: 5b128786d3789cde94e46465c9e91badd07a25d7
2019-04-19 20:33:04 -07:00
Fosco Marotto
6c2bf9e916 Add copyright headers per FB open-source checkup tool. (#5199)
Summary:
internal task: T35568575
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5199

Differential Revision: D14962794

Pulled By: gfosco

fbshipit-source-id: 93838ede6d0235eaecff90d200faed9a8515bbbe
2019-04-18 10:55:01 -07:00
Zhongyi Xie
baa5302447 Avoid double-compacting data in bottom level in manual compactions (#5138)
Summary:
Depending on the config, manual compaction (leveled compaction style) does following compactions:
L0->L1
L1->L2
...
Ln-1 -> Ln
Ln -> Ln
The final Ln -> Ln compaction is partly unnecessary as it recompacts all the files that were just generated by the Ln-1 -> Ln. We should avoid recompacting such files. This rule should be applied to Lmax only.
Resolves issue https://github.com/facebook/rocksdb/issues/4995
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5138

Differential Revision: D14940106

Pulled By: miasantreble

fbshipit-source-id: 8d3cf5507a17e76f3333cfd4bac5256d005636e5
2019-04-16 23:32:20 -07:00
jsteemann
8295d364e2 Improve transaction lock details (#5193)
Summary:
This branch contains two small improvements:
* Create `LockMap` entries using `std::make_shared`. This saves one heap allocation per LockMap entry but also locates the control block and the LockMap object closely together in memory, which can help with caching
* Reorder the members of `TrackedTrxInfo`, so that the resulting struct uses less memory (at least on 64bit systems)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5193

Differential Revision: D14934536

Pulled By: maysamyabandeh

fbshipit-source-id: f7b49812bb4b6029eef9d131e7cd56260df5b28e
2019-04-15 10:44:03 -07:00
Manuel Ung
d655a3aab7 Remove extraneous call to TrackKey (#5173)
Summary:
In `PessimisticTransaction::TryLock`, we were calling `TrackKey` even when assume_tracked=true, which defeats the purpose of assume_tracked. Remove this.

For keys that are already tracked, TrackKey will actually bump some counters (num_reads/num_writes) which are consumed in `TransactionBaseImpl::GetTrackedKeysSinceSavePoint`, and this is used to determine which keys were tracked since the last savepoint. I believe this functionality should still work, since I think the user should not call GetForUpdate/Put(assume_tracked=true) across savepoints, and if they do, they should not expect the Put(assume_tracked=true) to show up as a tracked key in the second savepoint.

This is another 2-3% cpu improvement.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5173

Differential Revision: D14883809

Pulled By: lth

fbshipit-source-id: 7d09f0772da422384af0519773e310c22b0cbca3
2019-04-12 16:37:12 -07:00
Maysam Yabandeh
fe642cbee6 WritePrepared: fix race condition in reading batch with duplicate keys (#5147)
Summary:
When ReadOption doesn't specify a snapshot, WritePrepared::Get used kMaxSequenceNumber to avoid the cost of creating a new snapshot object (that requires sync over db_mutex). This creates a race condition if it is reading from the writes of a transaction that had duplicate keys: each instance of duplicate key is inserted with a different sequence number and depending on the ordering the ::Get might skip the newer one and read the older one that is obsolete.
The patch fixes that by using last published seq as the snapshot sequence number. It also adds a check after the read is done to ensure that the max_evicted_seq has not advanced the aforementioned seq, which is a very unlikely event. If it did, then the read is not valid since the seq is not backed by an actually snapshot to let IsInSnapshot handle that properly when an overlapping commit is evicted from commit cache.
A unit  test is added to reproduce the race condition with duplicate keys.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5147

Differential Revision: D14758815

Pulled By: maysamyabandeh

fbshipit-source-id: a56915657132cf6ba5e3f5ea1b5d78c803407719
2019-04-12 14:40:41 -07:00
anand76
fefd4b98c5 Introduce a new MultiGet batching implementation (#5011)
Summary:
This PR introduces a new MultiGet() API, with the underlying implementation grouping keys based on SST file and batching lookups in a file. The reason for the new API is twofold - the definition allows callers to allocate storage for status and values on stack instead of std::vector, as well as return values as PinnableSlices in order to avoid copying, and it keeps the original MultiGet() implementation intact while we experiment with batching.

Batching is useful when there is some spatial locality to the keys being queries, as well as larger batch sizes. The main benefits are due to -
1. Fewer function calls, especially to BlockBasedTableReader::MultiGet() and FullFilterBlockReader::KeysMayMatch()
2. Bloom filter cachelines can be prefetched, hiding the cache miss latency

The next step is to optimize the binary searches in the level_storage_info, index blocks and data blocks, since we could reduce the number of key comparisons if the keys are relatively close to each other. The batching optimizations also need to be extended to other formats, such as PlainTable and filter formats. This also needs to be added to db_stress.

Benchmark results from db_bench for various batch size/locality of reference combinations are given below. Locality was simulated by offsetting the keys in a batch by a stride length. Each SST file is about 8.6MB uncompressed and key/value size is 16/100 uncompressed. To focus on the cpu benefit of batching, the runs were single threaded and bound to the same cpu to eliminate interference from other system events. The results show a 10-25% improvement in micros/op from smaller to larger batch sizes (4 - 32).

Batch   Sizes

1        | 2        | 4         | 8      | 16  | 32

Random pattern (Stride length 0)
4.158 | 4.109 | 4.026 | 4.05 | 4.1 | 4.074        - Get
4.438 | 4.302 | 4.165 | 4.122 | 4.096 | 4.075 - MultiGet (no batching)
4.461 | 4.256 | 4.277 | 4.11 | 4.182 | 4.14        - MultiGet (w/ batching)

Good locality (Stride length 16)
4.048 | 3.659 | 3.248 | 2.99 | 2.84 | 2.753
4.429 | 3.728 | 3.406 | 3.053 | 2.911 | 2.781
4.452 | 3.45 | 2.833 | 2.451 | 2.233 | 2.135

Good locality (Stride length 256)
4.066 | 3.786 | 3.581 | 3.447 | 3.415 | 3.232
4.406 | 4.005 | 3.644 | 3.49 | 3.381 | 3.268
4.393 | 3.649 | 3.186 | 2.882 | 2.676 | 2.62

Medium locality (Stride length 4096)
4.012 | 3.922 | 3.768 | 3.61 | 3.582 | 3.555
4.364 | 4.057 | 3.791 | 3.65 | 3.57 | 3.465
4.479 | 3.758 | 3.316 | 3.077 | 2.959 | 2.891

dbbench command used (on a DB with 4 levels, 12 million keys)-
TEST_TMPDIR=/dev/shm numactl -C 10  ./db_bench.tmp -use_existing_db=true -benchmarks="readseq,multireadrandom" -write_buffer_size=4194304 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=12000000 -reads=12000000 -duration=90 -threads=1 -compression_type=none -cache_size=4194304000 -batch_size=32 -disable_auto_compactions=true -bloom_bits=10 -cache_index_and_filter_blocks=true -pin_l0_filter_and_index_blocks_in_cache=true -multiread_batched=true -multiread_stride=4
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5011

Differential Revision: D14348703

Pulled By: anand1976

fbshipit-source-id: 774406dab3776d979c809522a67bedac6c17f84b
2019-04-11 14:28:26 -07:00
Manuel Ung
ef0fc1b461 Reduce copies of LockInfo (#5172)
Summary:
The LockInfo struct is not easy to copy because it contains std::vector. Reduce copies by using move constructor and `unordered_map::emplace`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5172

Differential Revision: D14882053

Pulled By: lth

fbshipit-source-id: 93999ec6ab1a5841fb5115abb764b6c1831a6de1
2019-04-10 15:58:58 -07:00
Siying Dong
0bb555630f Consolidate hash function used for non-persistent data in a new function (#5155)
Summary:
Create new function NPHash64() and GetSliceNPHash64(), which are currently
implemented using murmurhash.
Replace the current direct call of murmurhash() to use the new functions
if the hash results are not used in on-disk format.
This will make it easier to try out or switch to alternative functions
in the uses where data format compatibility doesn't need to be considered.
This part shouldn't have any performance impact.

Also, the sharded cache hash function is changed to the new format, because
it falls into this categoery. It doesn't show visible performance impact
in db_bench results. CPU showed by perf is increased from about 0.2% to 0.4%
in an extreme benchmark setting (4KB blocks, no-compression, everything
cached in block cache). We've known that the current hash function used,
our own Hash() has serious hash quality problem. It can generate a lots of
conflicts with similar input. In this use case, it means extra lock contention
for reads from the same file. This slight CPU regression is worthy to me
to counter the potential bad performance with hot keys. And hopefully this
will get further improved in the future with a better hash function.

cache_test's condition is relaxed a little bit to. The new hash is slightly
more skewed in this use case, but I manually checked the data and see
the hash results are still in a reasonable range.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5155

Differential Revision: D14834821

Pulled By: siying

fbshipit-source-id: ec9a2c0a2f8ae4b54d08b13a5c2e9cc97aa80cb5
2019-04-08 13:32:06 -07:00
Harry Wong
8d1e52165d Removed const fields in copyable classes (#5095)
Summary:
This fixed the compile error in Clang-8:
```
error: explicitly defaulted copy assignment operator is implicitly deleted [-Werror,-Wdefaulted-function-deleted]
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5095

Differential Revision: D14811961

Pulled By: riversand963

fbshipit-source-id: d935d1f85a4e8694dca10033fb5af92d8777eca0
2019-04-05 15:40:30 -07:00
Adam Simpkins
c06c4c01c5 Fix many bugs in log statement arguments (#5089)
Summary:
Annotate all of the logging functions to inform the compiler that these
use printf-style formatting arguments.  This allows the compiler to emit
warnings if the format arguments are incorrect.

This also fixes many problems reported now that format string checking
is enabled.  Many of these are simply mix-ups in the argument type (e.g,
int vs uint64_t), but in several cases the wrong number of arguments
were being passed in which can cause the code to crash.

The primary motivation for this was to fix the log message in
`DBImpl::SwitchMemtable()` which caused a segfault due to an extra %s
format parameter with no argument supplied.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5089

Differential Revision: D14574795

Pulled By: simpkins

fbshipit-source-id: 0921b03f0743652bf4ae21e414ff54b3bb65422a
2019-04-04 12:12:11 -07:00
Maysam Yabandeh
7441a0ecba WriteUnPrepared: fix ubsan complaint (#5148)
Summary:
Ubsna complains that in initialization of WriteUnpreparedTxnReadCallback the method of the child class is used before the parent class is constructed. The patch fixes that by making the aforementioned method static.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5148

Differential Revision: D14760098

Pulled By: maysamyabandeh

fbshipit-source-id: cf19b7c1fdb5de0a54e62c1deebe09a0fa048ded
2019-04-03 15:51:30 -07:00
Maysam Yabandeh
5234fc1b70 Mark logs with prepare in PreReleaseCallback (#5121)
Summary:
In prepare phase of 2PC, the db promises to remember the prepared data, for possible future commits. To fulfill the promise the prepared data must be persisted in the WAL so that they could be recovered after a crash. The log that contains a prepare batch that is not committed yet, is marked so that it is not garbage collected before the transaction commits/rollbacks. The bug was that the write to the log file and the mark of the file was not atomic, and WAL gc could have happened before the WAL log is actually marked. This patch moves the marking logic to PreReleaseCallback so that the WAL gc logic that joins both write threads would see the WAL write and WAL mark atomically.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5121

Differential Revision: D14665210

Pulled By: maysamyabandeh

fbshipit-source-id: 1d66aeb1c66a296cb4899a5a20c4d40c59e4b534
2019-04-02 15:17:47 -07:00
Maysam Yabandeh
14b3f683a1 WriteUnPrepared: less virtual in iterator callback (#5049)
Summary:
WriteUnPrepared adds a virtual function, MaxUnpreparedSequenceNumber, to ReadCallback, which returns 0 unless WriteUnPrepared is enabled and the transaction has uncommitted data written to the DB. Together with snapshot sequence number, this determines the last sequence that is visible to reads.
The patch clarifies the guarantees of the GetIterator API in WriteUnPrepared transactions and make use of that to statically initialize the read callback and thus avoid the virtual call.
Furthermore it increases the minimum value for min_uncommitted from 0 to 1 as seq 0 is used only for last level keys that are committed in all snapshots.

The following benchmark shows +0.26% higher throughput in seekrandom benchmark.

Benchmark:
./db_bench --benchmarks=fillrandom --use_existing_db=0 --num=1000000 --db=/dev/shm/dbbench

./db_bench --benchmarks=seekrandom[X10] --use_existing_db=1 --db=/dev/shm/dbbench --num=1000000 --duration=60 --seek_nexts=100
seekrandom [AVG    10 runs] : 20355 ops/sec;  225.2 MB/sec
seekrandom [MEDIAN 10 runs] : 20425 ops/sec;  225.9 MB/sec

./db_bench_lessvirtual3 --benchmarks=seekrandom[X10] --use_existing_db=1 --db=/dev/shm/dbbench --num=1000000 --duration=60 --seek_nexts=100
seekrandom [AVG    10 runs] : 20409 ops/sec;  225.8 MB/sec
seekrandom [MEDIAN 10 runs] : 20487 ops/sec;  226.6 MB/sec
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5049

Differential Revision: D14366459

Pulled By: maysamyabandeh

fbshipit-source-id: ebaff8908332a5ae9af7defeadabcb624be660ef
2019-04-02 14:47:16 -07:00
Maysam Yabandeh
a703f16da9 WriteUnPrepared: Enable auto-compaction after max_evicted_seq_ init (#5128)
Summary:
Compaction would depend on max_evicted_seq_ value. The ::Initialize method should do that after max_evicted_seq_ is properly initialized. The patch also back ports #4853 from WritePrepared txn to WriteUnPrepared.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5128

Differential Revision: D14686562

Pulled By: maysamyabandeh

fbshipit-source-id: b2355025712a72676ac3b20a95258adcf4774490
2019-03-29 13:18:57 -07:00
anand76
dae3b5545c Smooth the deletion of WAL files (#5116)
Summary:
WAL files are currently not subject to deletion rate limiting by DeleteScheduler. If the size of the WAL files is significant, this can cause a high delete rate on SSDs that may affect other operations. To fix it, force WAL file deletions to go through the SstFileManager. Original PR for this is #2768
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5116

Differential Revision: D14669437

Pulled By: anand1976

fbshipit-source-id: c5f62d0640cebaa1574de841a1d01e4ce2faadf0
2019-03-28 15:17:13 -07:00
Siying Dong
2b4d5ceb47 Remove some "using std::..." from header files. (#5113)
Summary:
The code convention we are following, Google C++ Style, discourage
alias in header files, especially public headers:
https://google.github.io/styleguide/cppguide.html#Aliases
Remove some of them. Might removed some from .cc files as well to be consistent.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5113

Differential Revision: D14633030

Pulled By: siying

fbshipit-source-id: b990edc919d5de60295992284f980195e501d424
2019-03-27 10:28:21 -07:00
Siying Dong
fe2bd190a5 BlobDB::Open() should put all existing trash files to delete scheduler (#5103)
Summary:
Right now, BlobDB::Open() fails to put all trash files to delete scheduler,
which causes some trash files permanently untracked.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5103

Differential Revision: D14606095

Pulled By: siying

fbshipit-source-id: 41a9437a2948abb235c0ed85f9a04612d0e50183
2019-03-26 10:53:19 -07:00
Rashmi Sharma
a4396f9218 Make it easier for users to load options from option file and set shared block cache. (#5063)
Summary:
[RocksDB] Make it easier for users to load options from option file and set shared block cache.
Right now, it requires several dynamic casting for users to set the shared block cache to their option struct cast from the option file.
If people don't do that, every CF of every DB will generate its own 8MB block cache. It's not a usable setting. So we are dragging every user who loads options from the file into such a mess.
Instead, we should allow them to pass their cache object to LoadLatestOptions() and LoadOptionsFromFile(), so that those loaded option structs will have the shared block cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5063

Differential Revision: D14518584

Pulled By: rashmishrm

fbshipit-source-id: c91430ff9425a0e67d76fc67931d755f491ca5aa
2019-03-21 16:25:28 -07:00
Shobhit Dayal
b45b1cde3e Feature for sampling and reporting compressibility (#4842)
Summary:
This is a feature to sample data-block compressibility and and report them as stats. 1 in N (tunable) blocks is sampled for compressibility using two algorithms:
1. lz4 or snappy for fast compression
2. zstd or zlib for slow but higher compression.

The stats are reported to the caller as raw-bytes and compressed-bytes. The block continues to be compressed for storage using the specified CompressionType.

The db_bench_tool how has a command line option for specifying the sampling rate. It's default value is 0 (no sampling). To test the overhead for a certain value, users can compare the performance of db_bench_tool, varying the sampling rate. It is unlikely to have a noticeable impact for high values like 20.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4842

Differential Revision: D13629011

Pulled By: shobhitdayal

fbshipit-source-id: 14ca668bcab6499b2a1734edf848eb62a4f4fafa
2019-03-18 12:15:34 -07:00
He Zhe
20d49da90c utilities: Fix build failure with -Werror=maybe-uninitialized (#5074)
Summary:
Initialize magic_number to zero to avoid such failure.
utilities/blob_db/blob_log_format.cc:91:3: error: 'magic_number' may be used
uninitialized in this function [-Werror=maybe-uninitialized]
   if (magic_number != kMagicNumber) {
   ^~

Signed-off-by: He Zhe <zhe.he@windriver.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5074

Differential Revision: D14505514

Pulled By: miasantreble

fbshipit-source-id: 4334462958c2b9c5a7c68c6ab24dadf94ad70902
2019-03-18 11:35:06 -07:00