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https://github.com/facebook/rocksdb.git
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26 lines
974 B
C
26 lines
974 B
C
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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// This source code is also licensed under the GPLv2 license found in the
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// COPYING file in the root directory of this source tree.
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//
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#pragma once
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#include "db/version_edit.h"
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#include "util/random.h"
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namespace rocksdb {
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static const uint32_t kFileReadSampleRate = 1024;
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extern bool should_sample_file_read();
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extern void sample_file_read_inc(FileMetaData*);
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inline bool should_sample_file_read() {
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return (Random::GetTLSInstance()->Next() % kFileReadSampleRate == 307);
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}
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inline void sample_file_read_inc(FileMetaData* meta) {
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meta->stats.num_reads_sampled.fetch_add(kFileReadSampleRate,
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std::memory_order_relaxed);
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}
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}
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