mirror of
https://github.com/facebook/rocksdb.git
synced 2024-12-04 20:02:50 +00:00
e34087c524
Summary: This is a simplified version of https://github.com/facebook/rocksdb/issues/13096, which called for a way to hook into long-running loops completely within RocksDB to change their thread priority (or similar). The current prime hook point is `DBIter::FindNextUserEntryInternal` likely because of iterating over tombstones. This is implemented using the weak symbol hack for ease of back-porting/patching, and while we get to know potential future requirements better for integration into the public API. (Consider potential relationships to `Env::GetThreadStatusUpdater()` and `TransactionDBMutexFactory`.) Pull Request resolved: https://github.com/facebook/rocksdb/pull/13103 Test Plan: Performance validated with db_bench and DEBUG_LEVEL=0: `./db_bench --benchmarks=fillseq,deleterandom,readseq[-X100] --value_size=1 --num=1000000` No consistent difference seen; variances likely in how DB / executable / memory were laid out. ``` With an empty hook: readseq [AVG 100 runs] : 1753018 (± 8850) ops/sec; 28.4 (± 0.1) MB/sec readseq [MEDIAN 100 runs] : 1763746 ops/sec; 28.6 MB/sec (recompile) readseq [AVG 100 runs] : 1789019 (± 10260) ops/sec; 29.0 (± 0.2) MB/sec readseq [MEDIAN 100 runs] : 1801849 ops/sec; 29.2 MB/sec Base: readseq [AVG 100 runs] : 1772196 (± 8240) ops/sec; 28.7 (± 0.1) MB/sec readseq [MEDIAN 100 runs] : 1780453 ops/sec; 28.9 MB/sec (recompile) readseq [AVG 100 runs] : 1777637 (± 7613) ops/sec; 28.8 (± 0.1) MB/sec readseq [MEDIAN 100 runs] : 1786657 ops/sec; 29.0 MB/sec With a functional hook (count number of calls into it): readseq [AVG 100 runs] : 1796733 (± 8854) ops/sec; 29.1 (± 0.1) MB/sec readseq [MEDIAN 100 runs] : 1804690 ops/sec; 29.3 MB/sec RocksDbThreadYield: 126915800 (recompile) readseq [AVG 100 runs] : 1775371 (± 10529) ops/sec; 28.8 (± 0.2) MB/sec readseq [MEDIAN 100 runs] : 1789046 ops/sec; 29.0 MB/sec RocksDbThreadYield: 126977000 Base: readseq [AVG 100 runs] : 1773071 (± 10657) ops/sec; 28.7 (± 0.2) MB/sec readseq [MEDIAN 100 runs] : 1783414 ops/sec; 28.9 MB/sec (recompile) readseq [AVG 100 runs] : 1750852 (± 10184) ops/sec; 28.4 (± 0.2) MB/sec readseq [MEDIAN 100 runs] : 1763587 ops/sec; 28.6 MB/sec ``` Reviewed By: george-reynya Differential Revision: D65235379 Pulled By: pdillinger fbshipit-source-id: 7829e4cc25a56d4c1801b8adf9c7f7aa49ab7aca
38 lines
1.3 KiB
C++
38 lines
1.3 KiB
C++
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under both the GPLv2 (found in the
|
|
// COPYING file in the root directory) and Apache 2.0 License
|
|
// (found in the LICENSE.Apache file in the root directory).
|
|
//
|
|
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file. See the AUTHORS file for names of contributors.
|
|
|
|
#pragma once
|
|
|
|
#include <string>
|
|
|
|
// Include the appropriate platform specific file below. If you are
|
|
// porting to a new platform, see "port_example.h" for documentation
|
|
// of what the new port_<platform>.h file must provide.
|
|
#if defined(ROCKSDB_PLATFORM_POSIX)
|
|
#include "port/port_posix.h"
|
|
#elif defined(OS_WIN)
|
|
#include "port/win/port_win.h"
|
|
#endif
|
|
|
|
#ifdef OS_LINUX
|
|
// A temporary hook into long-running RocksDB threads to support modifying their
|
|
// priority etc. This should become a public API hook once the requirements
|
|
// are better understood.
|
|
extern "C" void RocksDbThreadYield() __attribute__((__weak__));
|
|
#define ROCKSDB_THREAD_YIELD_HOOK() \
|
|
{ \
|
|
if (RocksDbThreadYield) { \
|
|
RocksDbThreadYield(); \
|
|
} \
|
|
}
|
|
#else
|
|
#define ROCKSDB_THREAD_YIELD_HOOK() \
|
|
{}
|
|
#endif
|