mirror of
https://github.com/facebook/rocksdb.git
synced 2024-12-04 20:02:50 +00:00
fdf882ded2
Summary: When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433 Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag. Differential Revision: D19977691 fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
48 lines
1.7 KiB
C++
48 lines
1.7 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.
|
|
//
|
|
|
|
// Compression context cache allows to cache compression/uncompression contexts
|
|
// This helps with Random Read latencies and reduces CPU utilization
|
|
// Caching is implemented using CoreLocal facility. Compression/Uncompression
|
|
// instances are cached on a per core basis using CoreLocalArray. A borrowed
|
|
// instance is atomically replaced with a sentinel value for the time of being
|
|
// used. If it turns out that another thread is already makes use of the
|
|
// instance we still create one on the heap which is later is destroyed.
|
|
|
|
#pragma once
|
|
|
|
#include <stdint.h>
|
|
|
|
#include "rocksdb/rocksdb_namespace.h"
|
|
|
|
namespace ROCKSDB_NAMESPACE {
|
|
class ZSTDUncompressCachedData;
|
|
|
|
class CompressionContextCache {
|
|
public:
|
|
// Singleton
|
|
static CompressionContextCache* Instance();
|
|
static void InitSingleton();
|
|
CompressionContextCache(const CompressionContextCache&) = delete;
|
|
CompressionContextCache& operator=(const CompressionContextCache&) = delete;
|
|
|
|
ZSTDUncompressCachedData GetCachedZSTDUncompressData();
|
|
void ReturnCachedZSTDUncompressData(int64_t idx);
|
|
|
|
private:
|
|
// Singleton
|
|
CompressionContextCache();
|
|
~CompressionContextCache();
|
|
|
|
class Rep;
|
|
Rep* rep_;
|
|
};
|
|
|
|
} // namespace ROCKSDB_NAMESPACE
|