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Diffstat (limited to 'src/rocksdb/monitoring/file_read_sample.h')
-rw-r--r-- | src/rocksdb/monitoring/file_read_sample.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/src/rocksdb/monitoring/file_read_sample.h b/src/rocksdb/monitoring/file_read_sample.h new file mode 100644 index 000000000..82a933e0a --- /dev/null +++ b/src/rocksdb/monitoring/file_read_sample.h @@ -0,0 +1,23 @@ +// 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; +extern bool should_sample_file_read(); +extern 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 |