Java Benchmark 基准测试的实例详解

Java Benchmark 基准测试的实例详解

java Benchmark 基准测试的实例详解

import java.util.Arrays;

import java.util.concurrent.TimeUnit;

import org.openjdk.jmh.annotations.Benchmark;

import org.openjdk.jmh.annotations.BenchmarkMode;

import org.openjdk.jmh.annotations.Measurement;

import org.openjdk.jmh.annotations.Mode;

import org.openjdk.jmh.annotations.OutputTimeUnit;

import org.openjdk.jmh.annotations.Scope;

import org.openjdk.jmh.annotations.State;

import org.openjdk.jmh.annotations.Threads;

import org.openjdk.jmh.annotations.Warmup;

import org.openjdk.jmh.runner.Runner;

import org.openjdk.jmh.runner.RunnerException;

import org.openjdk.jmh.runner.options.Options;

import org.openjdk.jmh.runner.options.OptionsBuilder;

@BenchmarkMode(Mode.Throughput)//基准测试类型

@OutputTimeUnit(TimeUnit.SECONDS)//基准测试结果的时间类型

@Warmup(iterations = 3)//预热的迭代次数

@Threads(2)//测试线程数量

@State(Scope.Thread)//该状态为每个线程独享

//度量:iterations进行测试的轮次，time每轮进行的时长，timeUnit时长单位,batchSize批次数量

@Measurement(iterations = 2, time = -1, timeUnit = TimeUnit.SECONDS, batchSize = -1)

public class InstructionsBenchmark{

static int staticPos = 0;

//String src = "SELECT a FROM ab , ee.ff AS f,(SELECT a FROM `schema_bb`.`tbl_bb`,(SELECT a FROM ccc AS c, `dddd`));";

final byte[] srcBytes = {83, 69, 76, 69, 67, 84, 32, 97, 32, 70, 82, 79, 77, 32, 97, 98, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 44, 32, 101, 101, 46, 102, 102, 32, 65, 83, 32, 102, 44, 40, 83, 69, 76, 69, 67, 84, 32, 97, 32, 70, 82, 79, 77, 32, 96, 115, 99, 104, 101, 109, 97, 95, 98, 98, 96, 46, 96, 116, 98, 108, 95, 98, 98, 96, 44, 40, 83, 69, 76, 69, 67, 84, 32, 97, 32, 70, 82, 79, 77, 32, 99, 99, 99, 32, 65, 83, 32, 99, 44, 32, 96, 100, 100, 100, 100, 96, 41, 41, 59};

int len = srcBytes.length;

byte[] array = new byte[8192];

int memberVariable = 0;

//run

public static void main(String[] args) throws RunnerException {

Options opt = new OptionsBuilder()

.include(InstructionsBenchmark.class.getSimpleName())

.forks(1)

// 使用之前要安装hsdis

//-XX:-TieredCompilation 关闭分层优化 -server

//-XX:+LogCompilation 运行之后项目路径会出现按照测试顺序输出hotspot_pid.log文件,可以使用JITWatch进行分析,可以根据最后运行的结果的顺序按文件时间找到对应的hotspot_pid.log文件

.jvmArgs("-XX:+UnlockDiagnosticVMOptions", "-XX:+LogCompilation", "-XX:+TraceClassLoading", "-XX:+PrintAssembly")

// .addProfiler(CompilerProfiler.class) // report JIT compiler profiling via standard MBeans

// .addProfiler(GCProfiler.class) // report GC time

// .addProfiler(StackProfiler.class) // report method stack execution profile

// .addProfiler(PausesProfiler.class)

/*

WinPerfAsmProfiler

You must install Windows Performance Toolkit. Once installed, locate directory with xperf.exe file

and either add it to PATH environment variable, or set it to jmh.perfasm.xperf.dir system property.

*/

//.addProfiler(WinPerfAsmProfiler.class)

//更多Profiler,请看JMH介绍

//.output("InstructionsBenchmark.log")//输出信息到文件

.build();

new Runner(opt).run();

}

//空循环 对照项

@Benchmark

public int emptyLoop() {

int pos = 0;

while (pos < len) {

++pos;

}

return pos;

}

@Benchmark

public int increment() {

int pos = 0;

int result = 0;

while (pos < len) {

++result;

++pos;

}

return result;

}

@Benchmark

public int decrement() {

int pos = 0;

int result = 0;

while (pos < len) {

--result;

++pos;

}

return result;

}

@Benchmark

public int ifElse() {

int pos = 0;

int result = 0;

while (pos < len) {

if (pos == 10) {

++result;

++pos;

} else {

++pos;

}

}

return result;

}

@Benchmark

public int ifElse2() {

int pos = 0;

int result = 0;

while (pos < len) {

if (pos == 10) {

++result;

++pos;

} else if (pos == 20) {

++result;

++pos;

} else {

++pos;

}

}

return result;

}

@Benchmark

public int ifnotElse() {

int pos = 0;

int result = 0;

while (pos < len) {

if (pos != 10) {

++pos;

} else {

++result;

++pos;

}

}

return result;

}

@Benchmark

public int ifLessthanElse() {

int pos = 0;

int result = 0;

while (pos < len) {

if (pos < 10) {

++pos;

} else {

++result;

++phttp://os;

}

}

return result;

}

@Benchmark

public int ifGreaterthanElse() {

int pos = 0;

int result = 0;

while (pos < len) {

if (pos > 10) {

++pos;

} else {

++result;

++pos;

}

}

return result;

}

@Benchmark

public int readMemberVariable_a_byteArray() {

int pos = 0;

int result = 0;

while (pos < len) {

result = srcBytes[pos];

pos++;

}

return result;

}

}

ops/time：标识每秒钟执行的次数

依赖jar包：

org.ojNzDzpenjdk.jmh

jmh-core

${jmh.version}

org.openjdk.jmh

jmh-generator-annprocess

${jmh.version}

provided

org.codehaus.mojo

exec-maven-plugin

run-benchmarks

integration-test

exec

test

java

-classpath

org.openjdk.jmh.Main

.*

以上就是Java Benchmark 基准测试，如有疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！

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