006_JMH JAVA基准测试
2019-04-01 本文已影响0人
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JMH JAVA基准测试
通过本篇文章你可以直到一下内容
- 什么是JMH
- JMH适用场景
- JMH入门级demo
- JMH如何测试业务代码
什么是JMH
JMH，即Java Microbenchmark Harness，这是专门用于进行代码的微基准测试的一套工具API。JMH 由 OpenJDK/Oracle 里面那群开发了 Java 编译器的大牛们所开发 。何谓 Micro Benchmark 呢？ 简单地说就是在 method 层面上的 benchmark()，精度可以精确到微秒级。
使用场景
- 实现同样一种功能有多种方式时，可以通过JMH可以知道使用哪种方式更加适合
- 可以通过JMH知道方法的性能如何
JMH入门级demo
独立项目运行demo
操作步骤
- 1.使用maven生成demo项目
mvn archetype:generate \
-DinteractiveMode=false \
-DarchetypeGroupId=org.openjdk.jmh \
-DarchetypeArtifactId=jmh-java-benchmark-archetype \
-DgroupId=io.four \
-DartifactId=jmh-demo \
-Dversion=1.0
通过上面的操作在当前目录中已经创建好了一个项目，导入到idea里面
- 2.编写测试方法
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
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.runner.Runner;
import org.openjdk.jmh.runner.RunnerException;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;
import org.openjdk.jmh.runner.options.TimeValue;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@BenchmarkMode(Mode.AverageTime)// 测试方法平均执行时间
@OutputTimeUnit(TimeUnit.MICROSECONDS)// 输出结果的时间粒度为微秒
public class MyBenchmark {
private static final Logger logger = LoggerFactory.getLogger(MyBenchmark.class);
@Benchmark
public void stringAdd() {
String str = "";
for(int i = 0 ; i < 100 ; i++){
str += "abc"+i;
}
}
@Benchmark
public void stringBufferAdd() {
StringBuffer str = new StringBuffer();
for(int i = 0 ; i < 100 ; i++){
str.append("abc").append(i);
}
}
public static void main(String[] args) throws RunnerException {
// 可以通过注解
Options opt = new OptionsBuilder()
.include(MyBenchmark.class.getSimpleName())
.warmupIterations(3) // 预热3次
.threads(8) // 10线程并发
.forks(1)//模拟一个线程执行
.build();
new Runner(opt).run();
}
}
上面的测试是验证使用String进行字符串拼接和使用StringBuffer进行字符串拼接两种方式哪种效率更高。得到的测试结果是求的平均响应时间
-
执行报告：
image.png
image.png
可以看到使用StringBuffer进行拼接的效果是使用String的大概6倍，当然如果调高for循环次数这个差别会更加明显，这里就不做更进一步的测试。
对于上面的注解不明白没有关系，后面会给出解释。
在项目中使用
如果你要在自己的项目中嵌套使用JMH，可以将上面独立项目的pom文件写到你自己项目中去。pom文件如下：
<dependencies>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.0.11</version>
</dependency>
<dependency>
<groupId>org.openjdk.jmh</groupId>
<artifactId>jmh-core</artifactId>
<version>${jmh.version}</version>
</dependency>
<dependency>
<groupId>org.openjdk.jmh</groupId>
<artifactId>jmh-generator-annprocess</artifactId>
<version>${jmh.version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.mph</groupId>
<artifactId>mph-user-service</artifactId>
<version>1.0.37-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>dubbo</artifactId>
<version>2.5.7</version>
</dependency>
</dependencies>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<!--
JMH version to use with this project.
-->
<jmh.version>1.21</jmh.version>
<!--
Java source/target to use for compilation.
-->
<javac.target>1.8</javac.target>
<!--
Name of the benchmark Uber-JAR to generate.
-->
<uberjar.name>benchmarks</uberjar.name>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<compilerVersion>${javac.target}</compilerVersion>
<source>${javac.target}</source>
<target>${javac.target}</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.2</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<finalName>${uberjar.name}</finalName>
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>org.openjdk.jmh.Main</mainClass>
</transformer>
</transformers>
<filters>
<filter>
<!--
Shading signed JARs will fail without this.
http://stackoverflow.com/questions/999489/invalid-signature-file-when-attempting-to-run-a-jar
-->
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/*.SF</exclude>
<exclude>META-INF/*.DSA</exclude>
<exclude>META-INF/*.RSA</exclude>
</excludes>
</filter>
</filters>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>2.5</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.1</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.1</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>2.4</version>
</plugin>
<plugin>
<artifactId>maven-javadoc-plugin</artifactId>
<version>2.9.1</version>
</plugin>
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>2.6</version>
</plugin>
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.3</version>
</plugin>
<plugin>
<artifactId>maven-source-plugin</artifactId>
<version>2.2.1</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.17</version>
</plugin>
</plugins>
</pluginManagement>
</build>
进行适当的修改即可
压测项目中的方法
使用独立的项目进行测试
下面这个例子是压测dubbo接口，目前微服务中接口都可以按照下面套路进行压测
- 1.导入相应的jar包
<!--下面是dubbo服务的jar包，一般接口定义都在这个jar包里面-->
<dependency>
<groupId>com.mph</groupId>
<artifactId>mph-user-service</artifactId>
<version>1.0.37-SNAPSHOT</version>
</dependency>
<!--dubbo依赖的jar包-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>dubbo</artifactId>
<version>2.5.7</version>
</dependency>
- 2.添加spring配置文件
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://code.alibabatech.com/schema/dubbo
http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
<dubbo:application name="demo-consumer"/>
<dubbo:registry address="zookeeper://192.168.19.124:2181"/>
<import resource="classpath:user-dubbo-reference-local.xml"/>
</beans>
上面是一个基本的dubbo消费端的基本配置有了上面配置之后就可以使用spring容器帮我们生成代理类
- 3.编写测试类
import java.util.concurrent.TimeUnit;
import javax.annotation.Resource;
import com.mph.coreapi.user.service.LoginUserService;
import com.rogrand.coreapi.user.entity.BizEnterpriseVipLog;
import com.rogrand.coreapi.user.service.BizEnterpriseVipLogService;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
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.Setup;
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;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* @Author: chao.zhu
* @description:
* @CreateDate: 2019/04/01
* @Version: 1.0
*/
@BenchmarkMode(Mode.AverageTime) //压测模式是平均执行时间
@Warmup(iterations = 3) //预热3轮
@Measurement(iterations = 10, time = 5, timeUnit = TimeUnit.SECONDS)//轮询次数10次，每次5秒
@Threads(8)//开8个线程执行
@Fork(1)//开一个进程
@OutputTimeUnit(TimeUnit.MILLISECONDS)//统计结果以毫秒为单位
@State(Scope.Benchmark)//整个JMH共享，与Setup同用
public class JmhByUserService {
private BizEnterpriseVipLogService bizEnterpriseVipLogService;
private LoginUserService loginUserService;
//这个是初始化方法，JMH会自动帮我们先调用这个方法对属性进行初始化动作。下面初始化了两个dubbo服务
@Setup
public void init(){
ApplicationContext ac = new ClassPathXmlApplicationContext("application-dubbo.xml");
bizEnterpriseVipLogService = ac.getBean("bizEnterpriseVipLogService",BizEnterpriseVipLogService.class);
loginUserService = ac.getBean("loginUserService",LoginUserService.class);
}
//压测其中一个dubbo服务的方法
@Benchmark
public void testStringAdd() {
bizEnterpriseVipLogService.getInfoByOsn("VP201805242028553504");
}
@Benchmark
public void testGetBaseUserInfo() {
loginUserService.findBaseUserByUid(5963308);
}
public static void main(String[] args) throws RunnerException {
Options options = new OptionsBuilder()
.include(JmhByUserService.class.getSimpleName())
.output("/rgec/log/jmh.log") //将执行结果导入到文件中
.build();
new Runner(options).run();
}
}
- 4.执行结果
# JMH version: 1.21
# VM version: JDK 1.8.0_131, Java HotSpot(TM) 64-Bit Server VM, 25.131-b11
# VM invoker: /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/bin/java
# VM options: -javaagent:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar=50091:/Applications/IntelliJ IDEA.app/Contents/bin -Dfile.encoding=UTF-8
# Warmup: 3 iterations, 10 s each
# Measurement: 10 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 8 threads, will synchronize iterations
# Benchmark mode: Average time, time/op
# Benchmark: co.speedar.infra.JmhByUserService.testGetBaseUserInfo
# Run progress: 0.00% complete, ETA 00:04:20
# Fork: 1 of 1
objc[5822]: Class JavaLaunchHelper is implemented in both /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/bin/java (0x1072c64c0) and /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/libinstrument.dylib (0x10733c4e0). One of the two will be used. Which one is undefined.
# Warmup Iteration 1: 23.168 ±(99.9%) 0.499 ms/op
# Warmup Iteration 2: 30.436 ±(99.9%) 0.327 ms/op
# Warmup Iteration 3: 24.817 ±(99.9%) 0.252 ms/op
Iteration 1: 23.209 ±(99.9%) 0.136 ms/op
Iteration 2: 25.345 ±(99.9%) 0.202 ms/op
Iteration 3: 24.625 ±(99.9%) 0.117 ms/op
Iteration 4: 25.249 ±(99.9%) 0.262 ms/op
Iteration 5: 25.351 ±(99.9%) 0.234 ms/op
Iteration 6: 25.588 ±(99.9%) 0.091 ms/op
Iteration 7: 25.380 ±(99.9%) 0.189 ms/op
Iteration 8: 24.204 ±(99.9%) 0.230 ms/op
Iteration 9: 24.308 ±(99.9%) 0.145 ms/op
Iteration 10: 23.958 ±(99.9%) 0.142 ms/op
Result "co.speedar.infra.JmhByUserService.testGetBaseUserInfo":
24.722 ±(99.9%) 1.189 ms/op [Average]
(min, avg, max) = (23.209, 24.722, 25.588), stdev = 0.786
CI (99.9%): [23.533, 25.911] (assumes normal distribution)
# JMH version: 1.21
# VM version: JDK 1.8.0_131, Java HotSpot(TM) 64-Bit Server VM, 25.131-b11
# VM invoker: /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/bin/java
# VM options: -javaagent:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar=50091:/Applications/IntelliJ IDEA.app/Contents/bin -Dfile.encoding=UTF-8
# Warmup: 3 iterations, 10 s each
# Measurement: 10 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 8 threads, will synchronize iterations
# Benchmark mode: Average time, time/op
# Benchmark: co.speedar.infra.JmhByUserService.testStringAdd
# Run progress: 50.00% complete, ETA 00:02:13
# Fork: 1 of 1
objc[5835]: Class JavaLaunchHelper is implemented in both /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/bin/java (0x1077e14c0) and /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/libinstrument.dylib (0x108fff4e0). One of the two will be used. Which one is undefined.
# Warmup Iteration 1: 9.161 ±(99.9%) 0.145 ms/op
# Warmup Iteration 2: 7.669 ±(99.9%) 0.035 ms/op
# Warmup Iteration 3: 7.951 ±(99.9%) 0.034 ms/op
Iteration 1: 7.144 ±(99.9%) 0.024 ms/op
Iteration 2: 7.340 ±(99.9%) 0.060 ms/op
Iteration 3: 7.233 ±(99.9%) 0.027 ms/op
Iteration 4: 7.746 ±(99.9%) 0.063 ms/op
Iteration 5: 7.162 ±(99.9%) 0.029 ms/op
Iteration 6: 6.929 ±(99.9%) 0.023 ms/op
Iteration 7: 7.078 ±(99.9%) 0.042 ms/op
Iteration 8: 6.443 ±(99.9%) 0.039 ms/op
Iteration 9: 6.645 ±(99.9%) 0.019 ms/op
Iteration 10: 6.867 ±(99.9%) 0.021 ms/op
Result "co.speedar.infra.JmhByUserService.testStringAdd":
7.059 ±(99.9%) 0.553 ms/op [Average]
(min, avg, max) = (6.443, 7.059, 7.746), stdev = 0.366
CI (99.9%): [6.506, 7.612] (assumes normal distribution)
# Run complete. Total time: 00:04:27
REMEMBER: The numbers below are just data. To gain reusable insights, you need to follow up on
why the numbers are the way they are. Use profilers (see -prof, -lprof), design factorial
experiments, perform baseline and negative tests that provide experimental control, make sure
the benchmarking environment is safe on JVM/OS/HW level, ask for reviews from the domain experts.
Do not assume the numbers tell you what you want them to tell.
Benchmark Mode Cnt Score Error Units
JmhByUserService.testGetBaseUserInfo avgt 10 24.722 ± 1.189 ms/op
JmhByUserService.testStringAdd avgt 10 7.059 ± 0.553 ms/op
通过上面的最后执行结果统计可以看出testGetBaseUserInfo执行效率24毫秒，testStringAdd执行效率7毫秒
参考文档
- 下面这篇文章中有每一个注解的含义，所以这里就不在重复说明了，大家可以直接去看看下面的文章
Java微基准测试框架JMH - 下面是官方的一些demo，也可以供大家学习
官方demo
项目源码:
JMH demo
