标签：scheduled span abs thread net http alt exe lang
某一个项目CPU占用率一直很高，经常在40%-50%之间，最近比较闲，就开始了挂查工作。
1.通过 jstack命令输出进程的堆栈信息
jstack 2788 >C:\log.txt
将堆栈信息输出到log.txt
"dubbo-remoting-client-heartbeat-thread-1" #46 daemon prio=5 os_prio=0 tid=0x000000005c53e000 nid=0x240c waiting on condition [0x000000006447f000] java.lang.Thread.State: WAITING (parking) at sun.misc.Unsafe.park(Native Method) - parking to wait for <0x00000000e17fc110> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039) at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1088) at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809) at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - None "Hashed wheel timer #1" #41 prio=5 os_prio=0 tid=0x000000005c53c800 nid=0x271c runnable [0x0000000063fae000] java.lang.Thread.State: RUNNABLE at java.lang.Thread.sleep(Native Method) at org.jboss.netty.util.HashedWheelTimer$Worker.waitForNextTick(HashedWheelTimer.java:504) at org.jboss.netty.util.HashedWheelTimer$Worker.run(HashedWheelTimer.java:402) at org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108) at java.lang.Thread.run(Thread.java:745) Locked ownable synchronizers: - None "DubboClientReconnectTimer-thread-1" #44 daemon prio=5 os_prio=0 tid=0x0000000059883800 nid=0x2700 waiting on condition [0x000000006362f000] java.lang.Thread.State: TIMED_WAITING (parking) at sun.misc.Unsafe.park(Native Method) - parking to wait for <0x00000000e1825be0> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject) at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215) at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078) at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093) at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809) at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745)
2. 通过ProcessExplorer查找CPU占用过高的线程
从图中可以看到，占用CPU过高的线程ID是8924,再将8924转换为16进行，在刚刚输出的log.txt中查询对应的堆栈信息。
之后再查询相应的代码。CPU过高一般都是有列循环了。
标签：scheduled span abs thread net http alt exe lang
原文地址：http://www.cnblogs.com/Gyoung/p/6273074.html
