Commit Graph

16 Commits

Author SHA1 Message Date
jsteemann
d1c0d3f358 Small issues (#4564)
Summary:
Couple of very minor improvements (typos in comments, full qualification of class name, reordering members of a struct to make it smaller)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4564

Differential Revision: D10510183

Pulled By: maysamyabandeh

fbshipit-source-id: c7ddf9bfbf2db08cd31896c3fd93789d3fa68c8b
2018-10-23 10:35:57 -07:00
Yi Wu
4f12d49daf Suppress clang analyzer error (#4299)
Summary:
Suppress multiple clang-analyzer error. All of them are clang false-positive.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4299

Differential Revision: D9430740

Pulled By: yiwu-arbug

fbshipit-source-id: fbdd575bdc214d124826d61d35a117995c509279
2018-08-21 16:43:05 -07:00
Gabriel Wicke
090c78a0d7 Support lowering CPU priority of background threads
Summary:
Background activities like compaction can negatively affect
latency of higher-priority tasks like request processing. To avoid this,
rocksdb already lowers the IO priority of background threads on Linux
systems. While this takes care of typical IO-bound systems, it does not
help much when CPU (temporarily) becomes the bottleneck. This is
especially likely when using more expensive compression settings.

This patch adds an API to allow for lowering the CPU priority of
background threads, modeled on the IO priority API. Benchmarks (see
below) show significant latency and throughput improvements when CPU
bound. As a result, workloads with some CPU usage bursts should benefit
from lower latencies at a given utilization, or should be able to push
utilization higher at a given request latency target.

A useful side effect is that compaction CPU usage is now easily visible
in common tools, allowing for an easier estimation of the contribution
of compaction vs. request processing threads.

As with IO priority, the implementation is limited to Linux, degrading
to a no-op on other systems.
Closes https://github.com/facebook/rocksdb/pull/3763

Differential Revision: D7740096

Pulled By: gwicke

fbshipit-source-id: e5d32373e8dc403a7b0c2227023f9ce4f22b413c
2018-04-24 08:41:51 -07:00
Andrew Kryczka
3cea61392f include thread-pool priority in thread names
Summary:
Previously threads were named "rocksdb:bg\<index in thread pool\>", so the first thread in all thread pools would be named "rocksdb:bg0". Users want to be able to distinguish threads used for flush (high-pri) vs regular compaction (low-pri) vs compaction to bottom-level (bottom-pri). So I changed the thread naming convention to include the thread-pool priority.
Closes https://github.com/facebook/rocksdb/pull/3702

Differential Revision: D7581415

Pulled By: ajkr

fbshipit-source-id: ce04482b6acd956a401ef22dc168b84f76f7d7c1
2018-04-18 17:27:56 -07:00
Andrew Kryczka
5a7e08468a fix ThreadStatus for bottom-pri compaction threads
Summary:
added `ThreadType::BOTTOM_PRIORITY` which is used in the `ThreadStatus` object to indicate the thread is used for bottom-pri compactions. Previously there was a bug where we mislabeled such threads as `ThreadType::LOW_PRIORITY`.
Closes https://github.com/facebook/rocksdb/pull/3270

Differential Revision: D6559428

Pulled By: ajkr

fbshipit-source-id: 96b1a50a9c19492b1a5fd1b77cf7061a6f9f1d1c
2017-12-14 14:57:49 -08:00
Andrew Kryczka
5b2cb64bfb Prevent threads from respawning during joining
Summary:
Previously the thread pool might be non-empty after joining since concurrent submissions could spawn new threads. This problem didn't affect our background flush/compaction thread pools because the `shutting_down_` flag prevented new jobs from being submitted during/after joining. But I wanted to be able to reuse the `ThreadPool` without such external synchronization.
Closes https://github.com/facebook/rocksdb/pull/2953

Differential Revision: D5951920

Pulled By: ajkr

fbshipit-source-id: 0efec7d0056d36d1338367da75e8b0c089bbc973
2017-10-03 16:27:28 -07:00
Andrew Kryczka
cc01985db0 Introduce bottom-pri thread pool for large universal compactions
Summary:
When we had a single thread pool for compactions, a thread could be busy for a long time (minutes) executing a compaction involving the bottom level. In multi-instance setups, the entire thread pool could be consumed by such bottom-level compactions. Then, top-level compactions (e.g., a few L0 files) would be blocked for a long time ("head-of-line blocking"). Such top-level compactions are critical to prevent compaction stalls as they can quickly reduce number of L0 files / sorted runs.

This diff introduces a bottom-priority queue for universal compactions including the bottom level. This alleviates the head-of-line blocking situation for fast, top-level compactions.

- Added `Env::Priority::BOTTOM` thread pool. This feature is only enabled if user explicitly configures it to have a positive number of threads.
- Changed `ThreadPoolImpl`'s default thread limit from one to zero. This change is invisible to users as we call `IncBackgroundThreadsIfNeeded` on the low-pri/high-pri pools during `DB::Open` with values of at least one. It is necessary, though, for bottom-pri to start with zero threads so the feature is disabled by default.
- Separated `ManualCompaction` into two parts in `PrepickedCompaction`. `PrepickedCompaction` is used for any compaction that's picked outside of its execution thread, either manual or automatic.
- Forward universal compactions involving last level to the bottom pool (worker thread's entry point is `BGWorkBottomCompaction`).
- Track `bg_bottom_compaction_scheduled_` so we can wait for bottom-level compactions to finish. We don't count them against the background jobs limits. So users of this feature will get an extra compaction for free.
Closes https://github.com/facebook/rocksdb/pull/2580

Differential Revision: D5422916

Pulled By: ajkr

fbshipit-source-id: a74bd11f1ea4933df3739b16808bb21fcd512333
2017-08-03 15:43:29 -07:00
Siying Dong
3c327ac2d0 Change RocksDB License
Summary: Closes https://github.com/facebook/rocksdb/pull/2589

Differential Revision: D5431502

Pulled By: siying

fbshipit-source-id: 8ebf8c87883daa9daa54b2303d11ce01ab1f6f75
2017-07-15 16:11:23 -07:00
Andrew Kryczka
6cc9aef162 New API for background work in single thread pool
Summary:
Previously users could set `max_background_flushes=0` to force rocksdb to use a single thread pool for both background flushes and compactions. That'll no longer be possible since I'm going to deprecate `max_background_flushes` and `max_background_compactions` in favor of a single option. This diff introduces a new way to force a single thread pool: when high-pri pool has zero threads, all background jobs will be submitted to low-pri pool.

Note the majority of the code change is adding `Env::GetBackgroundThreads()`, which is necessary to check whether the user has provided a zero-sized thread pool.
Closes https://github.com/facebook/rocksdb/pull/2204

Differential Revision: D4936256

Pulled By: ajkr

fbshipit-source-id: 929a07a0c0705f7766f5339cd013ff74e90d6e01
2017-05-23 11:12:27 -07:00
Siying Dong
d616ebea23 Add GPLv2 as an alternative license.
Summary: Closes https://github.com/facebook/rocksdb/pull/2226

Differential Revision: D4967547

Pulled By: siying

fbshipit-source-id: dd3b58ae1e7a106ab6bb6f37ab5c88575b125ab4
2017-04-27 18:06:12 -07:00
Siying Dong
d2dce5611a Move some files under util/ to separate dirs
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090

Differential Revision: D4833681

Pulled By: siying

fbshipit-source-id: 2fd8bef
2017-04-05 19:09:16 -07:00
Tamir Duberstein
253799c06d Add missing include for abort()
Summary:
Fixes #1233 (again).
Closes https://github.com/facebook/rocksdb/pull/1931

Differential Revision: D4625289

Pulled By: ajkr

fbshipit-source-id: 70e774e
2017-02-27 17:24:13 -08:00
Dmitri Smirnov
0a4cdde50a Windows thread
Summary:
introduce new methods into a public threadpool interface,
- allow submission of std::functions as they allow greater flexibility.
- add Joining methods to the implementation to join scheduled and submitted jobs with
  an option to cancel jobs that did not start executing.
- Remove ugly `#ifdefs` between pthread and std implementation, make it uniform.
- introduce pimpl for a drop in replacement of the implementation
- Introduce rocksdb::port::Thread typedef which is a replacement for std::thread.  On Posix Thread defaults as before std::thread.
- Implement WindowsThread that allocates memory in a more controllable manner than windows std::thread with a replaceable implementation.
- should be no functionality changes.
Closes https://github.com/facebook/rocksdb/pull/1823

Differential Revision: D4492902

Pulled By: siying

fbshipit-source-id: c74cb11
2017-02-06 14:54:18 -08:00
Daniel Black
bfbcec2339 Gcc 7 error expansion to defined
Summary:
sorry if these gcc-7/clang-4 cleanups are getting tedious.
Closes https://github.com/facebook/rocksdb/pull/1658

Differential Revision: D4318792

Pulled By: yiwu-arbug

fbshipit-source-id: 8e85891
2016-12-13 18:39:14 -08:00
sdong
f7669b40ba Fix Windows Build
Summary: Fix two Windows build problems.

Test Plan: Build on Windows and run all Linux tests.

Reviewers: IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D63189
2016-09-02 17:10:28 -07:00
Islam AbdelRahman
e9b2af87f8 Expose ThreadPool under include/rocksdb/threadpool.h
Summary:
This diff split ThreadPool to
-ThreadPool (abstract interface exposed in include/rocksdb/threadpool.h)
-ThreadPoolImpl (actual implementation in util/threadpool_imp.h)

This allow us to expose ThreadPool to the user so we can use it as an option later

Test Plan: existing unit tests

Reviewers: andrewkr, yiwu, yhchiang, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D62085
2016-08-26 10:41:35 -07:00