Java Metrics
Java Metrics是一个功能比較强大的java统计库，它的输出组件也非常强大，帮我们做好了：
- 输出到Ganglia
- 输出到控制台
- 输出到JMX
- 输出Json
具体见：dropwizard.github.io/metrics/
依赖
加入�依赖，如gradle:
compile "io.dropwizard.metrics:metrics-core:3.1.0" compile "io.dropwizard.metrics:metrics-ganglia:3.1.0"
假设须要ganglia输出功能，则须要metrics-ganglia包。我写的自己主动压測工具test-framework主要用失败计数，QPS统计。
统计调用频率
计数型的统计，比方计算失败次数，每次+1,则能够用Meter
public class GetStarted { static final MetricRegistry metrics = new MetricRegistry(); public static void main(String args[]) { startReport(); //metrics:事件总数，平均速率,包括1分钟，5分钟，15分钟的速率 Meter requests = metrics.meter("requests"); //计数一次 requests.mark(); wait5Seconds(); } static void startReport() { //注冊metrics,每一个1秒打印metrics到控制台 ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics) .convertRatesTo(TimeUnit.SECONDS) .convertDurationsTo(TimeUnit.MILLISECONDS) .build(); reporter.start(1, TimeUnit.SECONDS); } static void wait5Seconds() { try { Thread.sleep(5*1000); } catch(InterruptedException e) {} }} 效果：
14-10-14 21:28:53 ==============================================================-- Meters ----------------------------------------------------------------------requests count = 1 mean rate = 1.00 events/second 1-minute rate = 0.00 events/second 5-minute rate = 0.00 events/second 15-minute rate = 0.00 events/second14-10-14 21:28:54 ==============================================================-- Meters ----------------------------------------------------------------------requests count = 1 mean rate = 0.51 events/second 1-minute rate = 0.00 events/second 5-minute rate = 0.00 events/second 15-minute rate = 0.00 events/second14-10-14 21:28:55 ==============================================================-- Meters ----------------------------------------------------------------------requests count = 1 mean rate = 0.33 events/second 1-minute rate = 0.00 events/second 5-minute rate = 0.00 events/second 15-minute rate = 0.00 events/second14-10-14 21:28:56 ==============================================================-- Meters ----------------------------------------------------------------------requests count = 1 mean rate = 0.25 events/second 1-minute rate = 0.00 events/second 5-minute rate = 0.00 events/second 15-minute rate = 0.00 events/second14-10-14 21:28:57 ==============================================================-- Meters ----------------------------------------------------------------------requests count = 1 mean rate = 0.20 events/second 1-minute rate = 0.00 events/second 5-minute rate = 0.00 events/second 15-minute rate = 0.00 events/second
统计QPS
依据时间来计算qps，能够用Timer
public class TimerTest { static final MetricRegistry metrics = new MetricRegistry(); private static Timer timer = metrics.timer(MetricRegistry.name(TimerTest.class, "calculation-duration")); public static void main(String[] args) throws InterruptedException { // TODOAuto-generated method stub startReport(); Random rn = new Random(); while (true) { //统计開始 final Timer.Context context = timer.time(); int sleepTime = rn.nextInt(2000); Thread.sleep(sleepTime); System.out.println("处理耗时:" + sleepTime); //统计结束 context.stop(); } } static void startReport() { //注冊metrics,每一个1秒打印metrics到控制台 ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics) .convertRatesTo(TimeUnit.SECONDS) .convertDurationsTo(TimeUnit.MILLISECONDS) .build(); reporter.start(1, TimeUnit.SECONDS); }} 结果：
处理耗时:99614-10-14 22:40:34 ==============================================================-- Timers ----------------------------------------------------------------------com.edwardsbean.test.TimerTest.calculation-duration count = 1 mean rate = 0.91 calls/second 1-minute rate = 0.00 calls/second 5-minute rate = 0.00 calls/second 15-minute rate = 0.00 calls/second min = 995.91 milliseconds max = 995.91 milliseconds mean = 995.91 milliseconds stddev = 0.00 milliseconds median = 995.91 milliseconds 75% <= 995.91 milliseconds 95% <= 995.91 milliseconds 98% <= 995.91 milliseconds 99% <= 995.91 milliseconds 99.9% <= 995.91 milliseconds14-10-14 22:40:35 ==============================================================-- Timers ----------------------------------------------------------------------com.edwardsbean.test.TimerTest.calculation-duration count = 1 mean rate = 0.48 calls/second 1-minute rate = 0.00 calls/second 5-minute rate = 0.00 calls/second 15-minute rate = 0.00 calls/second min = 995.91 milliseconds max = 995.91 milliseconds mean = 995.91 milliseconds stddev = 0.00 milliseconds median = 995.91 milliseconds 75% <= 995.91 milliseconds 95% <= 995.91 milliseconds 98% <= 995.91 milliseconds 99% <= 995.91 milliseconds 99.9% <= 995.91 milliseconds
关于输出
每个输出组件都有一个相应的Reporter主类，比方Ganglia:
GMetric ganglia = new GMetric(address[0].getHostName(), address[0].getPort(), GMetric.UDPAddressingMode.MULTICAST, 1);GangliaReporter gangliaReporter = GangliaReporter.forRegistry(metricRegistry) .convertRatesTo(TimeUnit.SECONDS) .convertDurationsTo(TimeUnit.MILLISECONDS) .build(ganglia);//開始汇报gangliaReporter.start(1, TimeUnit.SECONDS);
而输出控制台的Reporter
###ConsoleReporter reporter = ConsoleReporter.forRegistry(metrics) .convertRatesTo(TimeUnit.SECONDS) .convertDurationsTo(TimeUnit.MILLISECONDS) .build();reporter.start(1, TimeUnit.SECONDS);