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https://github.com/facebook/rocksdb.git
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cd535c2280
Summary: In latest leaf's, MayContainHash() consistently consumes 5%~7% CPU usage. I checked the code and did an experiment with/without inlining this method. In release mode, with `1024 * 1024 * 256` bits and `1024 * 512` entries, both call 2^30 MayContainHash() with distinctive parameters. As the result showed, this patch reduced the running time from 9.127 sec to 7.891 sec. Test Plan: make check Reviewers: sdong, haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D15177
37 lines
1 KiB
C++
37 lines
1 KiB
C++
// Copyright (c) 2013, 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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#include "dynamic_bloom.h"
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#include "rocksdb/slice.h"
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#include "util/hash.h"
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namespace rocksdb {
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namespace {
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static uint32_t BloomHash(const Slice& key) {
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return Hash(key.data(), key.size(), 0xbc9f1d34);
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}
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}
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DynamicBloom::DynamicBloom(uint32_t total_bits,
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uint32_t (*hash_func)(const Slice& key),
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uint32_t num_probes)
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: hash_func_(hash_func),
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kTotalBits((total_bits + 7) / 8 * 8),
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kNumProbes(num_probes) {
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assert(hash_func_);
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assert(kNumProbes > 0);
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assert(kTotalBits > 0);
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data_.reset(new unsigned char[kTotalBits / 8]());
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}
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DynamicBloom::DynamicBloom(uint32_t total_bits,
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uint32_t num_probes)
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: DynamicBloom(total_bits, &BloomHash, num_probes) {
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}
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} // rocksdb
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