Added benchmark functionality on the lines of folly/Benchmark.h
Summary: Added benchmark functionality on the lines of folly/Benchmark.h Test Plan: Added unit tests Reviewers: igor, haobo, sdong, ljin, yhchiang, dhruba Reviewed By: igor CC: leveldb Differential Revision: https://reviews.facebook.net/D17973
This commit is contained in:
Pratyush Seth
parent
c7076a7a05
commit
ff1b5df4c6
2
.gitignore
vendored
2
.gitignore
vendored
@ -10,7 +10,7 @@ build_config.mk
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*.so
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*.so.*
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*_test
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*_bench
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*_benchmark
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*_stress
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*.out
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*.class
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26
Makefile
26
Makefile
@ -76,6 +76,7 @@ TESTS = \
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table_properties_collector_test \
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arena_test \
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auto_roll_logger_test \
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benchmarkharness_test \
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block_test \
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bloom_test \
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dynamic_bloom_test \
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@ -119,10 +120,10 @@ TOOLS = \
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db_stress \
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ldb \
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db_repl_stress \
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blob_store_bench
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blob_store_benchmark
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PROGRAMS = db_bench signal_test table_reader_bench $(TOOLS)
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BENCHMARKS = db_bench_sqlite3 db_bench_tree_db table_reader_bench
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PROGRAMS = db_benchmark signal_test table_reader_benchmark $(TOOLS)
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BENCHMARKS = db_bench_sqlite3 db_bench_tree_db table_reader_benchmark
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# The library name is configurable since we are maintaining libraries of both
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# debug/release mode.
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@ -245,8 +246,8 @@ $(LIBRARY): $(LIBOBJECTS)
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rm -f $@
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$(AR) -rs $@ $(LIBOBJECTS)
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db_bench: db/db_bench.o $(LIBOBJECTS) $(TESTUTIL)
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$(CXX) db/db_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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db_benchmark: db/db_benchmark.o $(LIBOBJECTS) $(TESTUTIL)
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$(CXX) db/db_benchmark.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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block_hash_index_test: table/block_hash_index_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) table/block_hash_index_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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@ -260,8 +261,8 @@ db_sanity_test: tools/db_sanity_test.o $(LIBOBJECTS) $(TESTUTIL)
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db_repl_stress: tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL)
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$(CXX) tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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blob_store_bench: tools/blob_store_bench.o $(LIBOBJECTS) $(TESTUTIL)
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$(CXX) tools/blob_store_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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blob_store_benchmark: tools/blob_store_benchmark.o $(LIBOBJECTS) $(TESTUTIL)
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$(CXX) tools/blob_store_benchmark.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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db_bench_sqlite3: doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL)
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$(CXX) doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lsqlite3 $(COVERAGEFLAGS)
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@ -308,6 +309,9 @@ stringappend_test: utilities/merge_operators/string_append/stringappend_test.o $
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redis_test: utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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benchmarkharness_test: util/benchmarkharness_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) util/benchmarkharness_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)
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histogram_test: util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)
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@ -323,8 +327,8 @@ crc32c_test: util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS)
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db_test: db/db_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) db/db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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log_write_bench: util/log_write_bench.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) util/log_write_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
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log_write_benchmark: util/log_write_benchmark.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) util/log_write_benchmark.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
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plain_table_db_test: db/plain_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) db/plain_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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@ -332,8 +336,8 @@ plain_table_db_test: db/plain_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
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simple_table_db_test: db/simple_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) db/simple_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
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table_reader_bench: table/table_reader_bench.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) table/table_reader_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
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table_reader_benchmark: table/table_reader_benchmark.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) table/table_reader_benchmark.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
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perf_context_test: db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS)
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$(CXX) db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
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@ -166,9 +166,9 @@ DIRS="util db table utilities"
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set -f # temporarily disable globbing so that our patterns arent expanded
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PRUNE_TEST="-name *test*.cc -prune"
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PRUNE_BENCH="-name *_bench.cc -prune"
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PORTABLE_FILES=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
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PORTABLE_CPP=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
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PRUNE_BENCHMARK="-name *_benchmark*.cc -prune"
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PORTABLE_FILES=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCHMARK -o -name '*.cc' -print | sort | tr "\n" " "`
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PORTABLE_CPP=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCHMARK -o -name '*.cpp' -print | sort | tr "\n" " "`
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set +f # re-enable globbing
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# The sources consist of the portable files, plus the platform-specific port
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414
util/benchmarkharness.cc
Normal file
414
util/benchmarkharness.cc
Normal file
@ -0,0 +1,414 @@
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// 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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//
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// This code is derived from Benchmark.cpp implemented in Folly, the opensourced
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// Facebook C++ library available at https://github.com/facebook/folly
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// The code has removed any dependence on other folly and boost libraries
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#include "util/benchmarkharness.h"
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#include <algorithm>
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#include <cmath>
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#include <cstring>
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#include <iostream>
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#include <limits>
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#include <string>
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#include <utility>
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#include <vector>
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using std::function;
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using std::get;
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using std::make_pair;
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using std::max;
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using std::min;
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using std::pair;
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using std::sort;
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using std::string;
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using std::tuple;
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using std::vector;
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DEFINE_bool(benchmark, false, "Run benchmarks.");
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DEFINE_int64(bm_min_usec, 100,
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"Minimum # of microseconds we'll accept for each benchmark.");
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DEFINE_int64(bm_min_iters, 1,
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"Minimum # of iterations we'll try for each benchmark.");
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DEFINE_int32(bm_max_secs, 1,
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"Maximum # of seconds we'll spend on each benchmark.");
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namespace rocksdb {
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namespace benchmark {
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BenchmarkSuspender::NanosecondsSpent BenchmarkSuspender::nsSpent;
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typedef function<uint64_t(unsigned int)> BenchmarkFun;
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static vector<tuple<const char*, const char*, BenchmarkFun>> benchmarks;
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// Add the global baseline
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BENCHMARK(globalBenchmarkBaseline) {
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asm volatile("");
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}
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void detail::AddBenchmarkImpl(const char* file, const char* name,
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BenchmarkFun fun) {
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benchmarks.emplace_back(file, name, std::move(fun));
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}
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/**
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* Given a point, gives density at that point as a number 0.0 < x <=
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* 1.0. The result is 1.0 if all samples are equal to where, and
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* decreases near 0 if all points are far away from it. The density is
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* computed with the help of a radial basis function.
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*/
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static double Density(const double * begin, const double *const end,
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const double where, const double bandwidth) {
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assert(begin < end);
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assert(bandwidth > 0.0);
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double sum = 0.0;
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for (auto i = begin; i < end; i++) {
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auto d = (*i - where) / bandwidth;
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sum += exp(- d * d);
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}
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return sum / (end - begin);
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}
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/**
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* Computes mean and variance for a bunch of data points. Note that
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* mean is currently not being used.
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*/
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static pair<double, double>
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MeanVariance(const double * begin, const double *const end) {
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assert(begin < end);
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double sum = 0.0, sum2 = 0.0;
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for (auto i = begin; i < end; i++) {
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sum += *i;
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sum2 += *i * *i;
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}
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auto const n = end - begin;
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return make_pair(sum / n, sqrt((sum2 - sum * sum / n) / n));
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}
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/**
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* Computes the mode of a sample set through brute force. Assumes
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* input is sorted.
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*/
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static double Mode(const double * begin, const double *const end) {
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assert(begin < end);
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// Lower bound and upper bound for result and their respective
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// densities.
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auto
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result = 0.0,
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bestDensity = 0.0;
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// Get the variance so we pass it down to Density()
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auto const sigma = MeanVariance(begin, end).second;
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if (!sigma) {
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// No variance means constant signal
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return *begin;
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}
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for (auto i = begin; i < end; i++) {
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assert(i == begin || *i >= i[-1]);
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auto candidate = Density(begin, end, *i, sigma * sqrt(2.0));
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if (candidate > bestDensity) {
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// Found a new best
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bestDensity = candidate;
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result = *i;
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} else {
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// Density is decreasing... we could break here if we definitely
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// knew this is unimodal.
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}
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}
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return result;
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}
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/**
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* Given a bunch of benchmark samples, estimate the actual run time.
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*/
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static double EstimateTime(double * begin, double * end) {
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assert(begin < end);
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// Current state of the art: get the minimum. After some
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// experimentation, it seems taking the minimum is the best.
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return *std::min_element(begin, end);
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// What follows after estimates the time as the mode of the
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// distribution.
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// Select the awesomest (i.e. most frequent) result. We do this by
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// sorting and then computing the longest run length.
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sort(begin, end);
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// Eliminate outliers. A time much larger than the minimum time is
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// considered an outlier.
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while (end[-1] > 2.0 * *begin) {
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--end;
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if (begin == end) {
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// LOG(INFO) << *begin;
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}
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assert(begin < end);
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}
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double result = 0;
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/* Code used just for comparison purposes */ {
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unsigned bestFrequency = 0;
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unsigned candidateFrequency = 1;
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double candidateValue = *begin;
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for (auto current = begin + 1; ; ++current) {
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if (current == end || *current != candidateValue) {
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// Done with the current run, see if it was best
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if (candidateFrequency > bestFrequency) {
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bestFrequency = candidateFrequency;
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result = candidateValue;
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}
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if (current == end) {
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break;
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}
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// Start a new run
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candidateValue = *current;
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candidateFrequency = 1;
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} else {
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// Cool, inside a run, increase the frequency
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++candidateFrequency;
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}
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}
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}
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result = Mode(begin, end);
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return result;
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}
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static double RunBenchmarkGetNSPerIteration(const BenchmarkFun& fun,
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const double globalBaseline) {
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// They key here is accuracy; too low numbers means the accuracy was
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// coarse. We up the ante until we get to at least minNanoseconds
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// timings.
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static uint64_t resolutionInNs = 0;
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if (!resolutionInNs) {
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timespec ts;
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ASSERT_EQ(0, clock_getres(detail::DEFAULT_CLOCK_ID, &ts));
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ASSERT_EQ(0, ts.tv_sec); // "Clock sucks.";
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ASSERT_LT(0, ts.tv_nsec); // "Clock too fast for its own good.";
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ASSERT_EQ(1, ts.tv_nsec); // "Clock too coarse, upgrade your kernel.";
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resolutionInNs = ts.tv_nsec;
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}
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// We choose a minimum minimum (sic) of 100,000 nanoseconds, but if
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// the clock resolution is worse than that, it will be larger. In
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// essence we're aiming at making the quantization noise 0.01%.
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static const auto minNanoseconds =
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max(FLAGS_bm_min_usec * 1000UL,
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min<uint64_t>(resolutionInNs * 100000, 1000000000ULL));
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// We do measurements in several epochs and take the minimum, to
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// account for jitter.
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static const unsigned int epochs = 1000;
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// We establish a total time budget as we don't want a measurement
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// to take too long. This will curtail the number of actual epochs.
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const uint64_t timeBudgetInNs = FLAGS_bm_max_secs * 1000000000;
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timespec global;
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ASSERT_EQ(0, clock_gettime(CLOCK_REALTIME, &global));
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double epochResults[epochs] = { 0 };
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size_t actualEpochs = 0;
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for (; actualEpochs < epochs; ++actualEpochs) {
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for (unsigned int n = FLAGS_bm_min_iters; n < (1UL << 30); n *= 2) {
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auto const nsecs = fun(n);
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if (nsecs < minNanoseconds) {
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continue;
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}
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// We got an accurate enough timing, done. But only save if
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// smaller than the current result.
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epochResults[actualEpochs] = max(0.0,
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static_cast<double>(nsecs) / n - globalBaseline);
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// Done with the current epoch, we got a meaningful timing.
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break;
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}
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timespec now;
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ASSERT_EQ(0, clock_gettime(CLOCK_REALTIME, &now));
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if (detail::TimespecDiff(now, global) >= timeBudgetInNs) {
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// No more time budget available.
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++actualEpochs;
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break;
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}
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}
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// If the benchmark was basically drowned in baseline noise, it's
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// possible it became negative.
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return max(0.0, EstimateTime(epochResults, epochResults + actualEpochs));
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}
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struct ScaleInfo {
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double boundary;
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const char* suffix;
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};
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static const ScaleInfo kTimeSuffixes[] {
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{ 365.25 * 24 * 3600, "years" },
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{ 24 * 3600, "days" },
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{ 3600, "hr" },
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{ 60, "min" },
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{ 1, "s" },
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{ 1E-3, "ms" },
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{ 1E-6, "us" },
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{ 1E-9, "ns" },
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{ 1E-12, "ps" },
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{ 1E-15, "fs" },
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{ 0, nullptr },
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};
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static const ScaleInfo kMetricSuffixes[] {
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{ 1E24, "Y" }, // yotta
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{ 1E21, "Z" }, // zetta
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{ 1E18, "X" }, // "exa" written with suffix 'X' so as to not create
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// confusion with scientific notation
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{ 1E15, "P" }, // peta
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{ 1E12, "T" }, // terra
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{ 1E9, "G" }, // giga
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{ 1E6, "M" }, // mega
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{ 1E3, "K" }, // kilo
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{ 1, "" },
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{ 1E-3, "m" }, // milli
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{ 1E-6, "u" }, // micro
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{ 1E-9, "n" }, // nano
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{ 1E-12, "p" }, // pico
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{ 1E-15, "f" }, // femto
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{ 1E-18, "a" }, // atto
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{ 1E-21, "z" }, // zepto
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{ 1E-24, "y" }, // yocto
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{ 0, nullptr },
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};
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static string HumanReadable(double n, unsigned int decimals,
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const ScaleInfo* scales) {
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if (std::isinf(n) || std::isnan(n)) {
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return std::to_string(n);
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}
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const double absValue = fabs(n);
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const ScaleInfo* scale = scales;
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while (absValue < scale[0].boundary && scale[1].suffix != nullptr) {
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++scale;
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}
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const double scaledValue = n / scale->boundary;
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char a[80];
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snprintf(a, sizeof(a), "%.*f%s", decimals, scaledValue, scale->suffix);
|
||||
return a;
|
||||
}
|
||||
|
||||
static string ReadableTime(double n, unsigned int decimals) {
|
||||
return HumanReadable(n, decimals, kTimeSuffixes);
|
||||
}
|
||||
|
||||
static string MetricReadable(double n, unsigned int decimals) {
|
||||
return HumanReadable(n, decimals, kMetricSuffixes);
|
||||
}
|
||||
|
||||
static void PrintBenchmarkResultsAsTable(
|
||||
const vector<tuple<const char*, const char*, double> >& data) {
|
||||
// Width available
|
||||
static const uint columns = 76;
|
||||
|
||||
// Compute the longest benchmark name
|
||||
size_t longestName = 0;
|
||||
for (auto i = 1; i < benchmarks.size(); i++) {
|
||||
longestName = max(longestName, strlen(get<1>(benchmarks[i])));
|
||||
}
|
||||
|
||||
// Print a horizontal rule
|
||||
auto separator = [&](char pad) {
|
||||
puts(string(columns, pad).c_str());
|
||||
};
|
||||
|
||||
// Print header for a file
|
||||
auto header = [&](const char* file) {
|
||||
separator('=');
|
||||
printf("%-*srelative time/iter iters/s\n",
|
||||
columns - 28, file);
|
||||
separator('=');
|
||||
};
|
||||
|
||||
double baselineNsPerIter = std::numeric_limits<double>::max();
|
||||
const char* lastFile = "";
|
||||
|
||||
for (auto& datum : data) {
|
||||
auto file = get<0>(datum);
|
||||
if (strcmp(file, lastFile)) {
|
||||
// New file starting
|
||||
header(file);
|
||||
lastFile = file;
|
||||
}
|
||||
|
||||
string s = get<1>(datum);
|
||||
if (s == "-") {
|
||||
separator('-');
|
||||
continue;
|
||||
}
|
||||
bool useBaseline /* = void */;
|
||||
if (s[0] == '%') {
|
||||
s.erase(0, 1);
|
||||
useBaseline = true;
|
||||
} else {
|
||||
baselineNsPerIter = get<2>(datum);
|
||||
useBaseline = false;
|
||||
}
|
||||
s.resize(columns - 29, ' ');
|
||||
auto nsPerIter = get<2>(datum);
|
||||
auto secPerIter = nsPerIter / 1E9;
|
||||
auto itersPerSec = 1 / secPerIter;
|
||||
if (!useBaseline) {
|
||||
// Print without baseline
|
||||
printf("%*s %9s %7s\n",
|
||||
static_cast<int>(s.size()), s.c_str(),
|
||||
ReadableTime(secPerIter, 2).c_str(),
|
||||
MetricReadable(itersPerSec, 2).c_str());
|
||||
} else {
|
||||
// Print with baseline
|
||||
auto rel = baselineNsPerIter / nsPerIter * 100.0;
|
||||
printf("%*s %7.2f%% %9s %7s\n",
|
||||
static_cast<int>(s.size()), s.c_str(),
|
||||
rel,
|
||||
ReadableTime(secPerIter, 2).c_str(),
|
||||
MetricReadable(itersPerSec, 2).c_str());
|
||||
}
|
||||
}
|
||||
separator('=');
|
||||
}
|
||||
|
||||
void RunBenchmarks() {
|
||||
ASSERT_TRUE(!benchmarks.empty());
|
||||
|
||||
vector<tuple<const char*, const char*, double>> results;
|
||||
results.reserve(benchmarks.size() - 1);
|
||||
|
||||
// PLEASE KEEP QUIET. MEASUREMENTS IN PROGRESS.
|
||||
|
||||
auto const globalBaseline = RunBenchmarkGetNSPerIteration(
|
||||
get<2>(benchmarks.front()), 0);
|
||||
for (auto i = 1; i < benchmarks.size(); i++) {
|
||||
double elapsed = 0.0;
|
||||
if (strcmp(get<1>(benchmarks[i]), "-") != 0) { // skip separators
|
||||
elapsed = RunBenchmarkGetNSPerIteration(get<2>(benchmarks[i]),
|
||||
globalBaseline);
|
||||
}
|
||||
results.emplace_back(get<0>(benchmarks[i]),
|
||||
get<1>(benchmarks[i]), elapsed);
|
||||
}
|
||||
|
||||
// PLEASE MAKE NOISE. MEASUREMENTS DONE.
|
||||
|
||||
PrintBenchmarkResultsAsTable(results);
|
||||
}
|
||||
|
||||
} // namespace benchmark
|
||||
} // namespace rocksdb
|
||||
407
util/benchmarkharness.h
Normal file
407
util/benchmarkharness.h
Normal file
@ -0,0 +1,407 @@
|
||||
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
|
||||
// This source code is licensed under the BSD-style license found in the
|
||||
// LICENSE file in the root directory of this source tree. An additional grant
|
||||
// of patent rights can be found in the PATENTS file in the same directory.
|
||||
//
|
||||
// This code is derived from Benchmark.h implemented in Folly, the opensourced
|
||||
// Facebook C++ library available at https://github.com/facebook/folly
|
||||
// The code has removed any dependence on other folly and boost libraries
|
||||
|
||||
#pragma once
|
||||
|
||||
#include <gflags/gflags.h>
|
||||
|
||||
#include <cassert>
|
||||
#include <ctime>
|
||||
#include <functional>
|
||||
#include <limits>
|
||||
|
||||
#include "util/testharness.h"
|
||||
|
||||
namespace rocksdb {
|
||||
namespace benchmark {
|
||||
|
||||
/**
|
||||
* Runs all benchmarks defined. Usually put in main().
|
||||
*/
|
||||
void RunBenchmarks();
|
||||
|
||||
namespace detail {
|
||||
|
||||
/**
|
||||
* This is the clock ID used for measuring time. On older kernels, the
|
||||
* resolution of this clock will be very coarse, which will cause the
|
||||
* benchmarks to fail.
|
||||
*/
|
||||
enum Clock { DEFAULT_CLOCK_ID = CLOCK_REALTIME };
|
||||
|
||||
/**
|
||||
* Adds a benchmark wrapped in a std::function. Only used
|
||||
* internally. Pass by value is intentional.
|
||||
*/
|
||||
void AddBenchmarkImpl(const char* file,
|
||||
const char* name,
|
||||
std::function<uint64_t(unsigned int)>);
|
||||
|
||||
/**
|
||||
* Takes the difference between two timespec values. end is assumed to
|
||||
* occur after start.
|
||||
*/
|
||||
inline uint64_t TimespecDiff(timespec end, timespec start) {
|
||||
if (end.tv_sec == start.tv_sec) {
|
||||
assert(end.tv_nsec >= start.tv_nsec);
|
||||
return end.tv_nsec - start.tv_nsec;
|
||||
}
|
||||
assert(end.tv_sec > start.tv_sec &&
|
||||
end.tv_sec - start.tv_sec <
|
||||
std::numeric_limits<uint64_t>::max() / 1000000000UL);
|
||||
return (end.tv_sec - start.tv_sec) * 1000000000UL
|
||||
+ end.tv_nsec - start.tv_nsec;
|
||||
}
|
||||
|
||||
/**
|
||||
* Takes the difference between two sets of timespec values. The first
|
||||
* two come from a high-resolution clock whereas the other two come
|
||||
* from a low-resolution clock. The crux of the matter is that
|
||||
* high-res values may be bogus as documented in
|
||||
* http://linux.die.net/man/3/clock_gettime. The trouble is when the
|
||||
* running process migrates from one CPU to another, which is more
|
||||
* likely for long-running processes. Therefore we watch for high
|
||||
* differences between the two timings.
|
||||
*
|
||||
* This function is subject to further improvements.
|
||||
*/
|
||||
inline uint64_t TimespecDiff(timespec end, timespec start,
|
||||
timespec endCoarse, timespec startCoarse) {
|
||||
auto fine = TimespecDiff(end, start);
|
||||
auto coarse = TimespecDiff(endCoarse, startCoarse);
|
||||
if (coarse - fine >= 1000000) {
|
||||
// The fine time is in all likelihood bogus
|
||||
return coarse;
|
||||
}
|
||||
return fine;
|
||||
}
|
||||
|
||||
} // namespace detail
|
||||
|
||||
|
||||
/**
|
||||
* Supporting type for BENCHMARK_SUSPEND defined below.
|
||||
*/
|
||||
struct BenchmarkSuspender {
|
||||
BenchmarkSuspender() {
|
||||
ASSERT_EQ(0, clock_gettime(detail::DEFAULT_CLOCK_ID, &start_));
|
||||
}
|
||||
|
||||
BenchmarkSuspender(const BenchmarkSuspender &) = delete;
|
||||
BenchmarkSuspender(BenchmarkSuspender && rhs) {
|
||||
start_ = rhs.start_;
|
||||
rhs.start_.tv_nsec = rhs.start_.tv_sec = 0;
|
||||
}
|
||||
|
||||
BenchmarkSuspender& operator=(const BenchmarkSuspender &) = delete;
|
||||
BenchmarkSuspender& operator=(BenchmarkSuspender && rhs) {
|
||||
if (start_.tv_nsec > 0 || start_.tv_sec > 0) {
|
||||
tally();
|
||||
}
|
||||
start_ = rhs.start_;
|
||||
rhs.start_.tv_nsec = rhs.start_.tv_sec = 0;
|
||||
return *this;
|
||||
}
|
||||
|
||||
~BenchmarkSuspender() {
|
||||
if (start_.tv_nsec > 0 || start_.tv_sec > 0) {
|
||||
tally();
|
||||
}
|
||||
}
|
||||
|
||||
void Dismiss() {
|
||||
assert(start_.tv_nsec > 0 || start_.tv_sec > 0);
|
||||
tally();
|
||||
start_.tv_nsec = start_.tv_sec = 0;
|
||||
}
|
||||
|
||||
void Rehire() {
|
||||
assert(start_.tv_nsec == 0 || start_.tv_sec == 0);
|
||||
ASSERT_EQ(0, clock_gettime(detail::DEFAULT_CLOCK_ID, &start_));
|
||||
}
|
||||
|
||||
/**
|
||||
* This helps the macro definition. To get around the dangers of
|
||||
* operator bool, returns a pointer to member (which allows no
|
||||
* arithmetic).
|
||||
*/
|
||||
/* implicit */
|
||||
operator int BenchmarkSuspender::*() const {
|
||||
return nullptr;
|
||||
}
|
||||
|
||||
/**
|
||||
* Accumulates nanoseconds spent outside benchmark.
|
||||
*/
|
||||
typedef uint64_t NanosecondsSpent;
|
||||
static NanosecondsSpent nsSpent;
|
||||
|
||||
private:
|
||||
void tally() {
|
||||
timespec end;
|
||||
ASSERT_EQ(0, clock_gettime(detail::DEFAULT_CLOCK_ID, &end));
|
||||
nsSpent += detail::TimespecDiff(end, start_);
|
||||
start_ = end;
|
||||
}
|
||||
|
||||
timespec start_;
|
||||
};
|
||||
|
||||
/**
|
||||
* Adds a benchmark. Usually not called directly but instead through
|
||||
* the macro BENCHMARK defined below. The lambda function involved
|
||||
* must take exactly one parameter of type unsigned, and the benchmark
|
||||
* uses it with counter semantics (iteration occurs inside the
|
||||
* function).
|
||||
*/
|
||||
template <typename Lambda>
|
||||
void
|
||||
AddBenchmark_n(const char* file, const char* name, Lambda&& lambda) {
|
||||
auto execute = [=](unsigned int times) -> uint64_t {
|
||||
BenchmarkSuspender::nsSpent = 0;
|
||||
timespec start, end;
|
||||
|
||||
// CORE MEASUREMENT STARTS
|
||||
auto const r1 = clock_gettime(detail::DEFAULT_CLOCK_ID, &start);
|
||||
lambda(times);
|
||||
auto const r2 = clock_gettime(detail::DEFAULT_CLOCK_ID, &end);
|
||||
// CORE MEASUREMENT ENDS
|
||||
|
||||
ASSERT_EQ(0, r1);
|
||||
ASSERT_EQ(0, r2);
|
||||
|
||||
return detail::TimespecDiff(end, start) - BenchmarkSuspender::nsSpent;
|
||||
};
|
||||
|
||||
detail::AddBenchmarkImpl(file, name,
|
||||
std::function<uint64_t(unsigned int)>(execute));
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds a benchmark. Usually not called directly but instead through
|
||||
* the macro BENCHMARK defined below. The lambda function involved
|
||||
* must take zero parameters, and the benchmark calls it repeatedly
|
||||
* (iteration occurs outside the function).
|
||||
*/
|
||||
template <typename Lambda>
|
||||
void
|
||||
AddBenchmark(const char* file, const char* name, Lambda&& lambda) {
|
||||
AddBenchmark_n(file, name, [=](unsigned int times) {
|
||||
while (times-- > 0) {
|
||||
lambda();
|
||||
}
|
||||
});
|
||||
}
|
||||
|
||||
} // namespace benchmark
|
||||
} // namespace rocksdb
|
||||
|
||||
/**
|
||||
* FB_ONE_OR_NONE(hello, world) expands to hello and
|
||||
* FB_ONE_OR_NONE(hello) expands to nothing. This macro is used to
|
||||
* insert or eliminate text based on the presence of another argument.
|
||||
*/
|
||||
#define FB_ONE_OR_NONE(a, ...) FB_THIRD(a, ## __VA_ARGS__, a)
|
||||
#define FB_THIRD(a, b, ...) __VA_ARGS__
|
||||
|
||||
#define FB_CONCATENATE_IMPL(s1, s2) s1##s2
|
||||
#define FB_CONCATENATE(s1, s2) FB_CONCATENATE_IMPL(s1, s2)
|
||||
|
||||
#define FB_ANONYMOUS_VARIABLE(str) FB_CONCATENATE(str, __LINE__)
|
||||
|
||||
#define FB_STRINGIZE(x) #x
|
||||
|
||||
/**
|
||||
* Introduces a benchmark function. Used internally, see BENCHMARK and
|
||||
* friends below.
|
||||
*/
|
||||
#define BENCHMARK_IMPL_N(funName, stringName, paramType, paramName) \
|
||||
static void funName(paramType); \
|
||||
static bool FB_ANONYMOUS_VARIABLE(rocksdbBenchmarkUnused) = ( \
|
||||
::rocksdb::benchmark::AddBenchmark_n(__FILE__, stringName, \
|
||||
[](paramType paramName) { funName(paramName); }), \
|
||||
true); \
|
||||
static void funName(paramType paramName)
|
||||
|
||||
#define BENCHMARK_IMPL(funName, stringName) \
|
||||
static void funName(); \
|
||||
static bool FB_ANONYMOUS_VARIABLE(rocksdbBenchmarkUnused) = ( \
|
||||
::rocksdb::benchmark::AddBenchmark(__FILE__, stringName, \
|
||||
[]() { funName(); }), \
|
||||
true); \
|
||||
static void funName()
|
||||
|
||||
/**
|
||||
* Introduces a benchmark function. Use with either one one or two
|
||||
* arguments. The first is the name of the benchmark. Use something
|
||||
* descriptive, such as insertVectorBegin. The second argument may be
|
||||
* missing, or could be a symbolic counter. The counter dictates how
|
||||
* many internal iteration the benchmark does. Example:
|
||||
*
|
||||
* BENCHMARK(vectorPushBack) {
|
||||
* vector<int> v;
|
||||
* v.push_back(42);
|
||||
* }
|
||||
*
|
||||
* BENCHMARK_N(insertVectorBegin, n) {
|
||||
* vector<int> v;
|
||||
* FOR_EACH_RANGE (i, 0, n) {
|
||||
* v.insert(v.begin(), 42);
|
||||
* }
|
||||
* }
|
||||
*/
|
||||
#define BENCHMARK_N(name, ...) \
|
||||
BENCHMARK_IMPL_N( \
|
||||
name, \
|
||||
FB_STRINGIZE(name), \
|
||||
FB_ONE_OR_NONE(unsigned, ## __VA_ARGS__), \
|
||||
__VA_ARGS__)
|
||||
|
||||
#define BENCHMARK(name) \
|
||||
BENCHMARK_IMPL( \
|
||||
name, \
|
||||
FB_STRINGIZE(name))
|
||||
|
||||
/**
|
||||
* Defines a benchmark that passes a parameter to another one. This is
|
||||
* common for benchmarks that need a "problem size" in addition to
|
||||
* "number of iterations". Consider:
|
||||
*
|
||||
* void pushBack(uint n, size_t initialSize) {
|
||||
* vector<int> v;
|
||||
* BENCHMARK_SUSPEND {
|
||||
* v.resize(initialSize);
|
||||
* }
|
||||
* FOR_EACH_RANGE (i, 0, n) {
|
||||
* v.push_back(i);
|
||||
* }
|
||||
* }
|
||||
* BENCHMARK_PARAM(pushBack, 0)
|
||||
* BENCHMARK_PARAM(pushBack, 1000)
|
||||
* BENCHMARK_PARAM(pushBack, 1000000)
|
||||
*
|
||||
* The benchmark above estimates the speed of push_back at different
|
||||
* initial sizes of the vector. The framework will pass 0, 1000, and
|
||||
* 1000000 for initialSize, and the iteration count for n.
|
||||
*/
|
||||
#define BENCHMARK_PARAM(name, param) \
|
||||
BENCHMARK_NAMED_PARAM(name, param, param)
|
||||
|
||||
/*
|
||||
* Like BENCHMARK_PARAM(), but allows a custom name to be specified for each
|
||||
* parameter, rather than using the parameter value.
|
||||
*
|
||||
* Useful when the parameter value is not a valid token for string pasting,
|
||||
* of when you want to specify multiple parameter arguments.
|
||||
*
|
||||
* For example:
|
||||
*
|
||||
* void addValue(uint n, int64_t bucketSize, int64_t min, int64_t max) {
|
||||
* Histogram<int64_t> hist(bucketSize, min, max);
|
||||
* int64_t num = min;
|
||||
* FOR_EACH_RANGE (i, 0, n) {
|
||||
* hist.addValue(num);
|
||||
* ++num;
|
||||
* if (num > max) { num = min; }
|
||||
* }
|
||||
* }
|
||||
*
|
||||
* BENCHMARK_NAMED_PARAM(addValue, 0_to_100, 1, 0, 100)
|
||||
* BENCHMARK_NAMED_PARAM(addValue, 0_to_1000, 10, 0, 1000)
|
||||
* BENCHMARK_NAMED_PARAM(addValue, 5k_to_20k, 250, 5000, 20000)
|
||||
*/
|
||||
#define BENCHMARK_NAMED_PARAM(name, param_name, ...) \
|
||||
BENCHMARK_IMPL( \
|
||||
FB_CONCATENATE(name, FB_CONCATENATE(_, param_name)), \
|
||||
FB_STRINGIZE(name) "(" FB_STRINGIZE(param_name) ")", \
|
||||
unsigned, \
|
||||
iters) { \
|
||||
name(iters, ## __VA_ARGS__); \
|
||||
}
|
||||
|
||||
/**
|
||||
* Just like BENCHMARK, but prints the time relative to a
|
||||
* baseline. The baseline is the most recent BENCHMARK() seen in
|
||||
* lexical order. Example:
|
||||
*
|
||||
* // This is the baseline
|
||||
* BENCHMARK_N(insertVectorBegin, n) {
|
||||
* vector<int> v;
|
||||
* FOR_EACH_RANGE (i, 0, n) {
|
||||
* v.insert(v.begin(), 42);
|
||||
* }
|
||||
* }
|
||||
*
|
||||
* BENCHMARK_RELATIVE_N(insertListBegin, n) {
|
||||
* list<int> s;
|
||||
* FOR_EACH_RANGE (i, 0, n) {
|
||||
* s.insert(s.begin(), 42);
|
||||
* }
|
||||
* }
|
||||
*
|
||||
* Any number of relative benchmark can be associated with a
|
||||
* baseline. Another BENCHMARK() occurrence effectively establishes a
|
||||
* new baseline.
|
||||
*/
|
||||
#define BENCHMARK_RELATIVE_N(name, ...) \
|
||||
BENCHMARK_IMPL_N( \
|
||||
name, \
|
||||
"%" FB_STRINGIZE(name), \
|
||||
FB_ONE_OR_NONE(unsigned, ## __VA_ARGS__), \
|
||||
__VA_ARGS__)
|
||||
|
||||
#define BENCHMARK_RELATIVE(name) \
|
||||
BENCHMARK_IMPL( \
|
||||
name, \
|
||||
"%" FB_STRINGIZE(name))
|
||||
|
||||
/**
|
||||
* A combination of BENCHMARK_RELATIVE and BENCHMARK_PARAM.
|
||||
*/
|
||||
#define BENCHMARK_RELATIVE_PARAM(name, param) \
|
||||
BENCHMARK_RELATIVE_NAMED_PARAM(name, param, param)
|
||||
|
||||
/**
|
||||
* A combination of BENCHMARK_RELATIVE and BENCHMARK_NAMED_PARAM.
|
||||
*/
|
||||
#define BENCHMARK_RELATIVE_NAMED_PARAM(name, param_name, ...) \
|
||||
BENCHMARK_IMPL( \
|
||||
FB_CONCATENATE(name, FB_CONCATENATE(_, param_name)), \
|
||||
"%" FB_STRINGIZE(name) "(" FB_STRINGIZE(param_name) ")", \
|
||||
unsigned, \
|
||||
iters) { \
|
||||
name(iters, ## __VA_ARGS__); \
|
||||
}
|
||||
|
||||
/**
|
||||
* Draws a line of dashes.
|
||||
*/
|
||||
#define BENCHMARK_DRAW_LINE() \
|
||||
static bool FB_ANONYMOUS_VARIABLE(rocksdbBenchmarkUnused) = ( \
|
||||
::rocksdb::benchmark::AddBenchmark(__FILE__, "-", []() { }), \
|
||||
true);
|
||||
|
||||
/**
|
||||
* Allows execution of code that doesn't count torward the benchmark's
|
||||
* time budget. Example:
|
||||
*
|
||||
* BENCHMARK_START_GROUP(insertVectorBegin, n) {
|
||||
* vector<int> v;
|
||||
* BENCHMARK_SUSPEND {
|
||||
* v.reserve(n);
|
||||
* }
|
||||
* FOR_EACH_RANGE (i, 0, n) {
|
||||
* v.insert(v.begin(), 42);
|
||||
* }
|
||||
* }
|
||||
*/
|
||||
#define BENCHMARK_SUSPEND \
|
||||
if (auto FB_ANONYMOUS_VARIABLE(BENCHMARK_SUSPEND) = \
|
||||
::rocksdb::benchmark::BenchmarkSuspender()) {} \
|
||||
else
|
||||
69
util/benchmarkharness_test.cc
Normal file
69
util/benchmarkharness_test.cc
Normal file
@ -0,0 +1,69 @@
|
||||
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
|
||||
// This source code is licensed under the BSD-style license found in the
|
||||
// LICENSE file in the root directory of this source tree. An additional grant
|
||||
// of patent rights can be found in the PATENTS file in the same directory.
|
||||
//
|
||||
|
||||
#include "util/benchmarkharness.h"
|
||||
#include <vector>
|
||||
|
||||
namespace rocksdb {
|
||||
namespace benchmark {
|
||||
|
||||
BENCHMARK(insertFrontVector) {
|
||||
std::vector<int> v;
|
||||
for (int i = 0; i < 100; i++) {
|
||||
v.insert(v.begin(), i);
|
||||
}
|
||||
}
|
||||
|
||||
BENCHMARK_RELATIVE(insertBackVector) {
|
||||
std::vector<int> v;
|
||||
for (int i = 0; i < 100; i++) {
|
||||
v.insert(v.end(), i);
|
||||
}
|
||||
}
|
||||
|
||||
BENCHMARK_N(insertFrontVector_n, n) {
|
||||
std::vector<int> v;
|
||||
for (int i = 0; i < n; i++) {
|
||||
v.insert(v.begin(), i);
|
||||
}
|
||||
}
|
||||
|
||||
BENCHMARK_RELATIVE_N(insertBackVector_n, n) {
|
||||
std::vector<int> v;
|
||||
for (int i = 0; i < n; i++) {
|
||||
v.insert(v.end(), i);
|
||||
}
|
||||
}
|
||||
|
||||
BENCHMARK_N(insertFrontEnd_n, n) {
|
||||
std::vector<int> v;
|
||||
for (int i = 0; i < n; i++) {
|
||||
v.insert(v.begin(), i);
|
||||
}
|
||||
for (int i = 0; i < n; i++) {
|
||||
v.insert(v.end(), i);
|
||||
}
|
||||
}
|
||||
|
||||
BENCHMARK_RELATIVE_N(insertFrontEndSuspend_n, n) {
|
||||
std::vector<int> v;
|
||||
for (int i = 0; i < n; i++) {
|
||||
v.insert(v.begin(), i);
|
||||
}
|
||||
BENCHMARK_SUSPEND {
|
||||
for (int i = 0; i < n; i++) {
|
||||
v.insert(v.end(), i);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
} // namespace benchmark
|
||||
} // namespace rocksdb
|
||||
|
||||
int main(int argc, char** argv) {
|
||||
rocksdb::benchmark::RunBenchmarks();
|
||||
return 0;
|
||||
}
|
||||
@ -12,7 +12,7 @@
|
||||
|
||||
// A simple benchmark to simulate transactional logs
|
||||
|
||||
DEFINE_int32(num_records, 6000, "Size of each record.");
|
||||
DEFINE_int32(num_records, 6000, "Number of records.");
|
||||
DEFINE_int32(record_size, 249, "Size of each record.");
|
||||
DEFINE_int32(record_interval, 10000, "Interval between records (microSec)");
|
||||
DEFINE_int32(bytes_per_sync, 0, "bytes_per_sync parameter in EnvOptions");
|
||||
@ -20,7 +20,7 @@ DEFINE_bool(enable_sync, false, "sync after each write.");
|
||||
|
||||
namespace rocksdb {
|
||||
void RunBenchmark() {
|
||||
std::string file_name = test::TmpDir() + "/log_write_bench.log";
|
||||
std::string file_name = test::TmpDir() + "/log_write_benchmark.log";
|
||||
Env* env = Env::Default();
|
||||
EnvOptions env_options;
|
||||
env_options.use_mmap_writes = false;
|
||||
Loading…
Reference in New Issue
Block a user