以下黑体加粗5步分析过程是重点
1 发现服务器访问出现卡顿现象
我们可以执行下top命令,看下机器负载情况,如果发现有CPU占用特别高的进程,则需要进一步排查
[root@localhost xsh]# toptop - 11:07:28 up 11 days, 23:50, 3 users, lclqd average: 0.22, 0.43, 0.56Tasks: 177 total, 2 running, 146 sleeping, 29 stopped, 0 zombie%Cpu(s): 14.5 us, 1.7 sy, 0.0 ni, 83.4 id, 0.0 wa, 0.0 hi, 0.3 si, 0.0 stKiB Mem : 7963508 total, 170068 free, 5578936 used, 2214504 buff/cacheKiB Swap: 4194300 total, 3195180 free, 999120 used. 2053828 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND10805 root 20 0 4706788 1.022g 5916 S 71.3 13.5 1411:16 java2161 root 20 0 3286620 406580 5700 S 0.3 5.1 158:12.77 java
2 输入:jstack -l pid > pid.stack 转储java线程运行状况。
[root@localhost clq]# jstack -l 10805 > 10805.stack
3 输入top -Hp Pid (由高到低依此列出cpu占用情况。)
[root@localhost xsh]# top -Hp 10805top - 11:07:28 up 11 days, 23:50, 3 users, lclqd average: 0.22, 0.43, 0.56%Cpu(s): 26.9 us, 1.3 sy, 0.0 ni, 71.6 id, 0.0 wa, 0.0 hi, 0.2 si, 0.0 stKiB Mem : 7963508 total, 306456 free, 5577664 used, 2079388 buff/cacheKiB Swap: 4194300 total, 3196672 free, 997628 used. 2054948 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND10985 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:30.15 java10986 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:28.96 java10988 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:25.90 java10989 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:25.63 java10991 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:26.85 java10992 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:26.41 java10993 root 20 0 4706788 1.015g 5916 S 11.3 13.4 106:28.55 java10987 root 20 0 4706788 1.015g 5916 S 11.0 13.4 106:26.44 java10990 root 20 0 4706788 1.015g 5916 R 11.0 13.4 106:26.54 java22409 root 20 0 4706788 1.015g 5916 S 10.0 13.4 0:02.09 java10813 root 20 0 4706788 1.015g 5916 S 0.3 13.4 63:30.13 java10814 root 20 0 4706788 1.015g 5916 S 0.3 13.4 63:27.61 java10815 root 20 0 4706788 1.015g 5916 S 0.3 13.4 63:28.07 java10816 root 20 0 4706788 1.015g 5916 S 0.3 13.4 63:27.36 java10805 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:00.00 java10812 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:09.81 java10817 root 20 0 4706788 1.015g 5916 S 0.0 13.4 17:50.33 java10818 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:00.45 java10819 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:00.67 java10820 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:00.00 java10821 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:18.51 java10822 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:20.36 java10823 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:00.00 java10824 root 20 0 4706788 1.015g 5916 S 0.0 13.4 0:59.87 java
4 把占用高的线程PID从10进制转换成16进制, 如10985 > 2AE9
2AE9到10805.stack搜索查看对应堆栈信息
"pool-4-thread-1" prio=10 tid=0x00007f27bc11a000 nid=0x2ae9 waiting on condition [0x00007f2768ef9000]java.lang.Thread.State: WAITING (parking)at sun.misc.Unsafe.park(Native Method)- parking to wait for <0x0000000090e1d048> (a java.util.concurrent.locks.ReentrantLock$FairSync)at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:834)at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:867)at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1197)at java.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:229)at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:290)at ch.qos.logback.core.OutputStreamAppender.subAppend(OutputStreamAppender.java:217)at ch.qos.logback.core.rolling.RollingFileAppender.subAppend(RollingFileAppender.java:182)at ch.qos.logback.core.OutputStreamAppender.append(OutputStreamAppender.java:103)at ch.qos.logback.core.UnsynchronizedAppenderBase.dclqppend(UnsynchronizedAppenderBase.java:88)at ch.qos.logback.core.spi.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:48)at ch.qos.logback.classic.Logger.appendLoopOnAppenders(Logger.java:273)at ch.qos.logback.classic.Logger.callAppenders(Logger.java:260)at ch.qos.logback.classic.Logger.buildLoggingEventAndAppend(Logger.java:442)at ch.qos.logback.classic.Logger.filterAndLog_1(Logger.java:414)at ch.qos.logback.classic.Logger.debug(Logger.java:507)at com.sun.proxy.$Proxy73.getAccountPushId(Unknown Source)at sun.reflect.GeneratedMethodAccessor569.invoke(Unknown Source)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:606)at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:333)at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)at com.alibaba.druid.support.spring.stat.DruidStatInterceptor.invoke(DruidStatInterceptor.java:72)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:738)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)at com.alibaba.druid.support.spring.stat.DruidStatInterceptor.invoke(DruidStatInterceptor.java:72)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:673)at com.clq.clq.rpc.service.clqImpl$$EnhancerBySpringCGLIB$$fefd630f.getAccountPushId(<generated>)at com.clq.clq..util.DealMsg.pDeal(DealMsg.java:138)- locked <0x00000000fbfd6a38> (a com.clq.clq.mc.util.DealMsg)at com.clq.clq.mc.util.DealPushMsg.DealMsg(DealMsg.java:342)- locked <0x00000000fbfd6a38> (a com.clq.clq.util.DealMsg)at com.clq.clq.mc.util.DealMsg.run(DealMsg.java:86)at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)at java.util.concurrent.FutureTask.run(FutureTask.java:262)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:178)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:292)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)at java.lang.Thread.run(Thread.java:745)
Locked ownable synchronizers:- <0x000000008ef451d8> (a java.util.concurrent.ThreadPoolExecutor$Worker)
5 根据对应代码,分析问题,解决问题。
如果你感觉不够方便可以安装TProfiler工具进行详细分析