fork of https://github.com/rust-rocksdb/rust-rocksdb for nextgraph
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
47 lines
1.7 KiB
47 lines
1.7 KiB
// 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
|
|
|