From e6918187568dbd01842d8d1d2c808ce16a894239 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 21 Apr 2024 13:54:28 +0200 Subject: Adding upstream version 18.2.2. Signed-off-by: Daniel Baumann --- src/rocksdb/util/compression_context_cache.h | 47 ++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 src/rocksdb/util/compression_context_cache.h (limited to 'src/rocksdb/util/compression_context_cache.h') diff --git a/src/rocksdb/util/compression_context_cache.h b/src/rocksdb/util/compression_context_cache.h new file mode 100644 index 000000000..7b7b2d507 --- /dev/null +++ b/src/rocksdb/util/compression_context_cache.h @@ -0,0 +1,47 @@ +// 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 + +#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 -- cgit v1.2.3