java版的Metric工具介绍-hustfxj-ChinaUnix博客
Metrics是一个给JAVA服务的各项指标提供度量工具的包,在JAVA代码中嵌入Metrics代码,可以方便的对业务代码的各个指标进行监控,同时,Metrics能够很好的跟Ganlia、Graphite结合,方便的提供图形化接口。基本使用方式直接将core包(目前稳定版本3.0.1)导入pom文件即可,配置如下:
<dependency> <groupId>com.codahale.metrics</groupId> <artifactId>metrics-core</artifactId> <version>3.0.1</version> </dependency>
core包主要提供如下核心功能:
- Metrics Registries类似一个metrics容器,维护一个Map,可以是一个服务一个实例。
- 支持五种metric类型:Gauges、Counters、Meters、Histograms和Timers。
- 可以将metrics值通过JMX、Console,CSV文件和SLF4J loggers发布出来。
五种Metrics类型:
1. Gauges
Gauges是一个最简单的计量,一般用来统计瞬时状态的数据信息,比如系统中处于pending状态的job。测试代码
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- package com.netease.test.metrics;
- import com.codahale.metrics.ConsoleReporter;
- import com.codahale.metrics.Gauge;
- import com.codahale.metrics.JmxReporter;
- import com.codahale.metrics.MetricRegistry;
- import java.util.Queue;
- import java.util.concurrent.LinkedBlockingDeque;
- import java.util.concurrent.TimeUnit;
- /**
- * User: hzwangxx
- * Date: 14-2-17
- * Time: 14:47
- * 测试Gauges,实时统计pending状态的job个数
- */
- public class TestGauges {
- /**
- * 实例化一个registry,最核心的一个模块,相当于一个应用程序的metrics系统的容器,维护一个Map
- */
- private static final MetricRegistry metrics = new MetricRegistry();
- private static Queue<String> queue = new LinkedBlockingDeque<String>();
- /**
- * 在控制台上打印输出
- */
- private static ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics).build();
- public static void main(String[] args) throws InterruptedException {
- reporter.start(3, TimeUnit.SECONDS);
- //实例化一个Gauge
- Gauge<Integer> gauge = new Gauge<Integer>() {
- @Override
- public Integer getValue() {
- return queue.size();
- }
- };
- //注册到容器中
- metrics.register(MetricRegistry.name(TestGauges.class, "pending-job", "size"), gauge);
- //测试JMX
- JmxReporter jmxReporter = JmxReporter.forRegistry(metrics).build();
- jmxReporter.start();
- //模拟数据
- for (int i=0; i<20; i++){
- queue.add("a");
- Thread.sleep(1000);
- }
- }
- }
- /*
- console output:
- 14-2-17 15:29:35 ===============================================================
- -- Gauges ----------------------------------------------------------------------
- com.netease.test.metrics.TestGauges.pending-job.size
- value = 4
- 14-2-17 15:29:38 ===============================================================
- -- Gauges ----------------------------------------------------------------------
- com.netease.test.metrics.TestGauges.pending-job.size
- value = 6
- 14-2-17 15:29:41 ===============================================================
- -- Gauges ----------------------------------------------------------------------
- com.netease.test.metrics.TestGauges.pending-job.size
- value = 9
- */
- JMX Gauges—提供给第三方库只通过JMX将指标暴露出来。
- Ratio Gauges—简单地通过创建一个gauge计算两个数的比值。
- Cached Gauges—对某些计量指标提供缓存
Derivative Gauges—提供Gauge的值是基于其他Gauge值的接口。
2. Counter
Counter是Gauge的一个特例,维护一个计数器,可以通过inc()和dec()方法对计数器做修改。使用步骤与Gauge基本类似,在MetricRegistry中提供了静态方法可以直接实例化一个Counter。
点击(此处)折叠或打开
- package com.netease.test.metrics;
- import com.codahale.metrics.ConsoleReporter;
- import com.codahale.metrics.Counter;
- import com.codahale.metrics.MetricRegistry;
- import java.util.LinkedList;
- import java.util.Queue;
- import java.util.concurrent.TimeUnit;
- import static com.codahale.metrics.MetricRegistry.*;
- /**
- * User: hzwangxx
- * Date: 14-2-14
- * Time: 14:02
- * 测试Counter
- */
- public class TestCounter {
- /**
- * 实例化一个registry,最核心的一个模块,相当于一个应用程序的metrics系统的容器,维护一个Map
- */
- private static final MetricRegistry metrics = new MetricRegistry();
- /**
- * 在控制台上打印输出
- */
- private static ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics).build();
- /**
- * 实例化一个counter,同样可以通过如下方式进行实例化再注册进去
- * pendingJobs = new Counter();
- * metrics.register(MetricRegistry.name(TestCounter.class, "pending-jobs"), pendingJobs);
- */
- private static Counter pendingJobs = metrics.counter(name(TestCounter.class, "pedding-jobs"));
- // private static Counter pendingJobs = metrics.counter(MetricRegistry.name(TestCounter.class, "pedding-jobs"));
- private static Queue<String> queue = new LinkedList<String>();
- public static void add(String str) {
- pendingJobs.inc();
- queue.offer(str);
- }
- public String take() {
- pendingJobs.dec();
- return queue.poll();
- }
- public static void main(String[]args) throws InterruptedException {
- reporter.start(3, TimeUnit.SECONDS);
- while(true){
- add("1");
- Thread.sleep(1000);
- }
- }
- }
- /*
- console output:
- 14-2-17 17:52:34 ===============================================================
- -- Counters --------------------------------------------------------------------
- com.netease.test.metrics.TestCounter.pedding-jobs
- count = 4
- 14-2-17 17:52:37 ===============================================================
- -- Counters --------------------------------------------------------------------
- com.netease.test.metrics.TestCounter.pedding-jobs
- count = 6
- 14-2-17 17:52:40 ===============================================================
- -- Counters --------------------------------------------------------------------
- com.netease.test.metrics.TestCounter.pedding-jobs
- count = 9
- */
Meters用来度量某个时间段的平均处理次数(request per second),每1、5、15分钟的TPS。比如一个service的请求数,通过metrics.meter()实例化一个Meter之后,然后通过meter.mark()方法就能将本次请求记录下来。统计结果有总的请求数,平均每秒的请求数,以及最近的1、5、15分钟的平均TPS。
点击(此处)折叠或打开
- package com.netease.test.metrics;
- import com.codahale.metrics.ConsoleReporter;
- import com.codahale.metrics.Meter;
- import com.codahale.metrics.MetricRegistry;
- import java.util.concurrent.TimeUnit;
- import static com.codahale.metrics.MetricRegistry.*;
- /**
- * User: hzwangxx
- * Date: 14-2-17
- * Time: 18:34
- * 测试Meters
- */
- public class TestMeters {
- /**
- * 实例化一个registry,最核心的一个模块,相当于一个应用程序的metrics系统的容器,维护一个Map
- */
- private static final MetricRegistry metrics = new MetricRegistry();
- /**
- * 在控制台上打印输出
- */
- private static ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics).build();
- /**
- * 实例化一个Meter
- */
- private static final Meter requests = metrics.meter(name(TestMeters.class, "request"));
- public static void handleRequest() {
- requests.mark();
- }
- public static void main(String[] args) throws InterruptedException {
- reporter.start(3, TimeUnit.SECONDS);
- while(true){
- handleRequest();
- Thread.sleep(100);
- }
- }
- }
- /*
- 14-2-17 18:43:08 ===============================================================
- -- Meters ----------------------------------------------------------------------
- com.netease.test.metrics.TestMeters.request
- count = 30
- mean rate = 9.95 events/second
- 1-minute rate = 0.00 events/second
- 5-minute rate = 0.00 events/second
- 15-minute rate = 0.00 events/second
- 14-2-17 18:43:11 ===============================================================
- -- Meters ----------------------------------------------------------------------
- com.netease.test.metrics.TestMeters.request
- count = 60
- mean rate = 9.99 events/second
- 1-minute rate = 10.00 events/second
- 5-minute rate = 10.00 events/second
- 15-minute rate = 10.00 events/second
- 14-2-17 18:43:14 ===============================================================
- -- Meters ----------------------------------------------------------------------
- com.netease.test.metrics.TestMeters.request
- count = 90
- mean rate = 9.99 events/second
- 1-minute rate = 10.00 events/second
- 5-minute rate = 10.00 events/second
- 15-minute rate = 10.00 events/second
- */
Histograms主要使用来统计数据的分布情况,最大值、最小值、平均值、中位数,百分比(75%、90%、95%、98%、99%和99.9%)。例如,需要统计某个页面的请求响应时间分布情况,可以使用该种类型的Metrics进行统计。具体的样例代码如下:
点击(此处)折叠或打开
- package com.netease.test.metrics;
- import com.codahale.metrics.ConsoleReporter;
- import com.codahale.metrics.Histogram;
- import com.codahale.metrics.MetricRegistry;
- import java.util.Random;
- import java.util.concurrent.TimeUnit;
- import static com.codahale.metrics.MetricRegistry.name;
- /**
- * User: hzwangxx
- * Date: 14-2-17
- * Time: 18:34
- * 测试Histograms
- */
- public class TestHistograms {
- /**
- * 实例化一个registry,最核心的一个模块,相当于一个应用程序的metrics系统的容器,维护一个Map
- */
- private static final MetricRegistry metrics = new MetricRegistry();
- /**
- * 在控制台上打印输出
- */
- private static ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics).build();
- /**
- * 实例化一个Histograms
- */
- private static final Histogram randomNums = metrics.histogram(name(TestHistograms.class, "random"));
- public static void handleRequest(double random) {
- randomNums.update((int) (random*100));
- }
- public static void main(String[] args) throws InterruptedException {
- reporter.start(3, TimeUnit.SECONDS);
- Random rand = new Random();
- while(true){
- handleRequest(rand.nextDouble());
- Thread.sleep(100);
- }
- }
- }
- /*
- 14-2-17 19:39:11 ===============================================================
- -- Histograms ------------------------------------------------------------------
- com.netease.test.metrics.TestHistograms.random
- count = 30
- min = 1
- max = 97
- mean = 45.93
- stddev = 29.12
- median = 39.50
- 75% <= 71.00
- 95% <= 95.90
- 98% <= 97.00
- 99% <= 97.00
- 99.9% <= 97.00
- 14-2-17 19:39:14 ===============================================================
- -- Histograms ------------------------------------------------------------------
- com.netease.test.metrics.TestHistograms.random
- count = 60
- min = 0
- max = 97
- mean = 41.17
- stddev = 28.60
- median = 34.50
- 75% <= 69.75
- 95% <= 92.90
- 98% <= 96.56
- 99% <= 97.00
- 99.9% <= 97.00
- 14-2-17 19:39:17 ===============================================================
- -- Histograms ------------------------------------------------------------------
- com.netease.test.metrics.TestHistograms.random
- count = 90
- min = 0
- max = 97
- mean = 44.67
- stddev = 28.47
- median = 43.00
- 75% <= 71.00
- 95% <= 91.90
- 98% <= 96.18
- 99% <= 97.00
- 99.9% <= 97.00
- */
5. Timers
Timers主要是用来统计某一块代码段的执行时间以及其分布情况,具体是基于Histograms和Meters来实现的。样例代码如下:
点击(此处)折叠或打开
- package com.netease.test.metrics;
- import com.codahale.metrics.ConsoleReporter;
- import com.codahale.metrics.MetricRegistry;
- import com.codahale.metrics.Timer;
- import java.util.Random;
- import java.util.concurrent.TimeUnit;
- import static com.codahale.metrics.MetricRegistry.name;
- /**
- * User: hzwangxx
- * Date: 14-2-17
- * Time: 18:34
- * 测试Timers
- */
- public class TestTimers {
- /**
- * 实例化一个registry,最核心的一个模块,相当于一个应用程序的metrics系统的容器,维护一个Map
- */
- private static final MetricRegistry metrics = new MetricRegistry();
- /**
- * 在控制台上打印输出
- */
- private static ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics).build();
- /**
- * 实例化一个Meter
- */
- // private static final Timer requests = metrics.timer(name(TestTimers.class, "request"));
- private static final Timer requests = metrics.timer(name(TestTimers.class, "request"));
- public static void handleRequest(int sleep) {
- Timer.Context context = requests.time();
- try {
- //some operator
- Thread.sleep(sleep);
- } catch (InterruptedException e) {
- e.printStackTrace();
- } finally {
- context.stop();
- }
- }
- public static void main(String[] args) throws InterruptedException {
- reporter.start(3, TimeUnit.SECONDS);
- Random random = new Random();
- while(true){
- handleRequest(random.nextInt(1000));
- }
- }
- }
- /*
- 14-2-18 9:31:54 ================================================================
- -- Timers ----------------------------------------------------------------------
- com.netease.test.metrics.TestTimers.request
- count = 4
- mean rate = 1.33 calls/second
- 1-minute rate = 0.00 calls/second
- 5-minute rate = 0.00 calls/second
- 15-minute rate = 0.00 calls/second
- min = 483.07 milliseconds
- max = 901.92 milliseconds
- mean = 612.64 milliseconds
- stddev = 196.32 milliseconds
- median = 532.79 milliseconds
- 75% <= 818.31 milliseconds
- 95% <= 901.92 milliseconds
- 98% <= 901.92 milliseconds
- 99% <= 901.92 milliseconds
- 99.9% <= 901.92 milliseconds
- 14-2-18 9:31:57 ================================================================
- -- Timers ----------------------------------------------------------------------
- com.netease.test.metrics.TestTimers.request
- count = 8
- mean rate = 1.33 calls/second
- 1-minute rate = 1.40 calls/second
- 5-minute rate = 1.40 calls/second
- 15-minute rate = 1.40 calls/second
- min = 41.07 milliseconds
- max = 968.19 milliseconds
- mean = 639.50 milliseconds
- stddev = 306.12 milliseconds
- median = 692.77 milliseconds
- 75% <= 885.96 milliseconds
- 95% <= 968.19 milliseconds
- 98% <= 968.19 milliseconds
- 99% <= 968.19 milliseconds
- 99.9% <= 968.19 milliseconds
- 14-2-18 9:32:00 ================================================================
- -- Timers ----------------------------------------------------------------------
- com.netease.test.metrics.TestTimers.request
- count = 15
- mean rate = 1.67 calls/second
- 1-minute rate = 1.40 calls/second
- 5-minute rate = 1.40 calls/second
- 15-minute rate = 1.40 calls/second
- min = 41.07 milliseconds
- max = 968.19 milliseconds
- mean = 591.35 milliseconds
- stddev = 302.96 milliseconds
- median = 650.56 milliseconds
- 75% <= 838.07 milliseconds
- 95% <= 968.19 milliseconds
- 98% <= 968.19 milliseconds
- 99% <= 968.19 milliseconds
- 99.9% <= 968.19 milliseconds
- */
Metrics提供了一个独立的模块:Health Checks,用于对Application、其子模块或者关联模块的运行是否正常做检测。该模块是独立metrics-core模块的,使用时则导入metrics-healthchecks包。
<dependency> <groupId>com.codahale.metrics</groupId> <artifactId>metrics-healthchecks</artifactId> <version>3.0.1</version> </dependency>
使用起来和与上述几种类型的Metrics有点类似,但是需要重新实例化一个Metrics容器HealthCheckRegistry,待检测模块继承抽象类HealthCheck并实现check()方法即可,然后将该模块注册到HealthCheckRegistry中,判断的时候通过isHealthy()接口即可。如下示例代码:
点击(此处)折叠或打开
- package com.netease.test.metrics;
- import com.codahale.metrics.health.HealthCheck;
- import com.codahale.metrics.health.HealthCheckRegistry;
- import java.util.Map;
- import java.util.Random;
- /**
- * User: hzwangxx
- * Date: 14-2-18
- * Time: 9:57
- */
- public class DatabaseHealthCheck extends HealthCheck{
- private final Database database;
- public DatabaseHealthCheck(Database database) {
- this.database = database;
- }
- @Override
- protected Result check() throws Exception {
- if (database.ping()) {
- return Result.healthy();
- }
- return Result.unhealthy("Can't ping database.");
- }
- /**
- * 模拟Database对象
- */
- static class Database {
- /**
- * 模拟database的ping方法
- * @return 随机返回boolean值
- */
- public boolean ping() {
- Random random = new Random();
- return random.nextBoolean();
- }
- }
- public static void main(String[] args) {
- // MetricRegistry metrics = new MetricRegistry();
- // ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics).build();
- HealthCheckRegistry registry = new HealthCheckRegistry();
- registry.register("database1", new DatabaseHealthCheck(new Database()));
- registry.register("database2", new DatabaseHealthCheck(new Database()));
- while (true) {
- for (Map.Entry<String, Result> entry : registry.runHealthChecks().entrySet()) {
- if (entry.getValue().isHealthy()) {
- System.out.println(entry.getKey() + ": OK");
- } else {
- System.err.println(entry.getKey() + ": FAIL, error message: " + entry.getValue().getMessage());
- final Throwable e = entry.getValue().getError();
- if (e != null) {
- e.printStackTrace();
- }
- }
- }
- try {
- Thread.sleep(1000);
- } catch (InterruptedException e) {
- }
- }
- }
- }
- /*
- console output:
- database1: OK
- database2: FAIL, error message: Can't ping database.
- database1: FAIL, error message: Can't ping database.
- database2: OK
- database1: OK
- database2: FAIL, error message: Can't ping database.
- database1: FAIL, error message: Can't ping database.
- database2: OK
- database1: FAIL, error message: Can't ping database.
- database2: FAIL, error message: Can't ping database.
- database1: FAIL, error message: Can't ping database.
- database2: FAIL, error message: Can't ping database.
- database1: OK
- database2: OK
- database1: OK
- database2: FAIL, error message: Can't ping database.
- database1: FAIL, error message: Can't ping database.
- database2: OK
- database1: OK
- database2: OK
- database1: FAIL, error message: Can't ping database.
- database2: OK
- database1: OK
- database2: OK
- database1: OK
- database2: OK
- database1: OK
- database2: FAIL, error message: Can't ping database.
- database1: FAIL, error message: Can't ping database.
- database2: FAIL, error message: Can't ping database.
- */
metrics提供了对Ehcache、Apache HttpClient、JDBI、Jersey、Jetty、Log4J、Logback、JVM等的集成,可以方便地将Metrics输出到Ganglia、Graphite中,供用户图形化展示。