// 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). // #pragma once #include "db/version_edit.h" #include "util/random.h" namespace ROCKSDB_NAMESPACE { static const uint32_t kFileReadSampleRate = 1024; bool should_sample_file_read(); void sample_file_read_inc(FileMetaData*); inline bool should_sample_file_read() { return (Random::GetTLSInstance()->Next() % kFileReadSampleRate == 307); } inline void sample_file_read_inc(FileMetaData* meta) { meta->stats.num_reads_sampled.fetch_add(kFileReadSampleRate, std::memory_order_relaxed); } } // namespace ROCKSDB_NAMESPACE