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// 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
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