JVM命令-jstack

- 日理万妓 2022-11-28 13:26 139阅读 0赞

## 一、简介 ##

jstack用法

/opt/java8/bin/jstack
    
    Usage:
        jstack [-l] <pid>
            (to connect to running process) 连接活动线程
        jstack -F [-m] [-l] <pid>
            (to connect to a hung process) 连接阻塞线程
        jstack [-m] [-l] <executable> <core>
            (to connect to a core file) 连接dump的文件
        jstack [-m] [-l] [server_id@]<remote server IP or hostname>
            (to connect to a remote debug server) 连接远程服务器
    
    Options:
        -F  to force a thread dump. Use when jstack <pid> does not respond (process is hung)
        -m  to print both java and native frames (mixed mode)
        -l  long listing. Prints additional information about locks
        -h or -help to print this help message

## 二、示例 ##

**2.1 jstack查看输出**

/opt/java8/bin/jstack -l 28367
    
    2019-06-25 15:04:46
    Full thread dump Java HotSpot(TM) 64-Bit Server VM (25.77-b03 mixed mode):
    
    "Attach Listener" #453 daemon prio=9 os_prio=0 tid=0x00007f9f94001000 nid=0xf30 waiting on condition [0x0000000000000000]
       java.lang.Thread.State: RUNNABLE
    
       Locked ownable synchronizers:
            - None
    
    "grpc-default-executor-263" #452 daemon prio=5 os_prio=0 tid=0x00007f9f4c01f800 nid=0x9aa waiting on condition [0x00007f9f398bd000]
       java.lang.Thread.State: TIMED_WAITING (parking)
            at sun.misc.Unsafe.park(Native Method)
            - parking to wait for  <0x00000007400243f0> (a java.util.concurrent.SynchronousQueue$TransferStack)
            at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
            at java.util.concurrent.SynchronousQueue$TransferStack.awaitFulfill(SynchronousQueue.java:460)
            at java.util.concurrent.SynchronousQueue$TransferStack.transfer(SynchronousQueue.java:362)
            at java.util.concurrent.SynchronousQueue.poll(SynchronousQueue.java:941)
            at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1066)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
            at java.lang.Thread.run(Thread.java:745)
    
       Locked ownable synchronizers:
            - None
    
    "http-bio-8080-exec-10" #235 daemon prio=5 os_prio=0 tid=0x0000000001bcc800 nid=0x3c13 waiting on condition [0x00007f9f384a9000]
       java.lang.Thread.State: WAITING (parking)
            at sun.misc.Unsafe.park(Native Method)
            - parking to wait for  <0x0000000743d26638> (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.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
            at org.apache.tomcat.util.threads.TaskQueue.take(TaskQueue.java:104)
            at org.apache.tomcat.util.threads.TaskQueue.take(TaskQueue.java:32)
            at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
            at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
            at java.lang.Thread.run(Thread.java:745)
    
       Locked ownable synchronizers:
            - None

**2.2 jstack统计线程数**

jstack -l 28367 | grep 'java.lang.Thread.State' | wc -l

或者

ps hH p pid | wc -l

**2.3 jstack检测死锁**

"mythread2" #12 prio=5 os_prio=0 tid=0x0000000058ef7800 nid=0x1ab4 waiting on condition [0x0000000059f8f000]
       java.lang.Thread.State: WAITING (parking)
            at sun.misc.Unsafe.park(Native Method)
            - parking to wait for  <0x00000000d602d610> (a java.util.concurrent.lock
    s.ReentrantLock$NonfairSync)
            at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInt
    errupt(AbstractQueuedSynchronizer.java:836)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(A
    bstractQueuedSynchronizer.java:870)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(Abstrac
    tQueuedSynchronizer.java:1199)
            at java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLo
    ck.java:209)
            at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
    
            at DeathLock$2.run(DeathLock.java:34)
    
       Locked ownable synchronizers:
            - <0x00000000d602d640> (a java.util.concurrent.locks.ReentrantLock$Nonfa
    irSync)
    
    "mythread1" #11 prio=5 os_prio=0 tid=0x0000000058ef7000 nid=0x3e68 waiting on condition [0x000000005947f000]
       java.lang.Thread.State: WAITING (parking)
            at sun.misc.Unsafe.park(Native Method)
            - parking to wait for  <0x00000000d602d640> (a java.util.concurrent.lock
    s.ReentrantLock$NonfairSync)
            at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInt
    errupt(AbstractQueuedSynchronizer.java:836)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(A
    bstractQueuedSynchronizer.java:870)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(Abstrac
    tQueuedSynchronizer.java:1199)
            at java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLo
    ck.java:209)
            at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
    
            at DeathLock$1.run(DeathLock.java:22)
    
       Locked ownable synchronizers:
            - <0x00000000d602d610> (a java.util.concurrent.locks.ReentrantLock$Nonfa
    irSync)
    
    
    Found one Java-level deadlock:
    =============================
    "mythread2":
      waiting for ownable synchronizer 0x00000000d602d610, (a java.util.concurrent.l
    ocks.ReentrantLock$NonfairSync),
      which is held by "mythread1"
    "mythread1":
      waiting for ownable synchronizer 0x00000000d602d640, (a java.util.concurrent.l
    ocks.ReentrantLock$NonfairSync),
      which is held by "mythread2"
    
    Java stack information for the threads listed above:
    ===================================================
    "mythread2":
            at sun.misc.Unsafe.park(Native Method)
            - parking to wait for  <0x00000000d602d610> (a java.util.concurrent.lock
    s.ReentrantLock$NonfairSync)
            at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInt
    errupt(AbstractQueuedSynchronizer.java:836)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(A
    bstractQueuedSynchronizer.java:870)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(Abstrac
    tQueuedSynchronizer.java:1199)
            at java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLo
    ck.java:209)
            at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
    
            at DeathLock$2.run(DeathLock.java:34)
    "mythread1":
            at sun.misc.Unsafe.park(Native Method)
            - parking to wait for  <0x00000000d602d640> (a java.util.concurrent.lock
    s.ReentrantLock$NonfairSync)
            at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInt
    errupt(AbstractQueuedSynchronizer.java:836)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(A
    bstractQueuedSynchronizer.java:870)
            at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(Abstrac
    tQueuedSynchronizer.java:1199)
            at java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLo
    ck.java:209)
            at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285)
    
            at DeathLock$1.run(DeathLock.java:22)
    
    Found 1 deadlock.

本文转载自: https://www.jianshu.com/p/8d5782bc596e