Java线程挂起而没有死锁 [英] Java Thread hanging without deadlocks

问题描述

我目前正在挂起一个进程.

I am currently having some trouble with a process that is hanging.

首先，下面的线程转储没有显示死锁.另一个有趣的事情是该过程挂在java.lang.System.identityHashCode方法上.该进程当前的CPU使用率为0％，有时最高为1％.通常，该进程使用100％.它正在使用1.7GB的RAM(此过程正常).该计算机具有大量的CPU，磁盘空间和RAM.

First of all, the below thread dump shows no deadlock. Another interesting thing is that the process is hanging at java.lang.System.identityHashCode method. The currently CPU usage of that process is 0%, sometimes peaks at 1%... normally the process uses 100%. It is using 1.7GB of RAM (which is normal for this process). The machine has plenty of CPUs, disk space and RAM available.

Attaching to process ID 4146, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 23.7-b01
Deadlock Detection:

No deadlocks found.

Thread 12761: (state = BLOCKED)


Thread 4159: (state = BLOCKED)


Thread 4158: (state = BLOCKED)
 - java.lang.Object.wait(long) @bci=0 (Interpreted frame)
 - java.lang.ref.ReferenceQueue.remove(long) @bci=44, line=135 (Interpreted frame)
 - java.lang.ref.ReferenceQueue.remove() @bci=2, line=151 (Interpreted frame)
 - java.lang.ref.Finalizer$FinalizerThread.run() @bci=3, line=177 (Interpreted frame)


Thread 4157: (state = BLOCKED)
 - java.lang.Object.wait(long) @bci=0 (Interpreted frame)
 - java.lang.Object.wait() @bci=2, line=503 (Interpreted frame)
 - java.lang.ref.Reference$ReferenceHandler.run() @bci=46, line=133 (Interpreted frame)


Thread 4147: (state = IN_VM)
 - java.lang.System.identityHashCode(java.lang.Object) @bci=0 (Compiled frame; information may be imprecise)
 - java.util.IdentityHashMap.hash(java.lang.Object, int) @bci=1, line=301 (Compiled frame)
 - java.util.IdentityHashMap.containsKey(java.lang.Object) @bci=17, line=358 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=18, line=346 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.FastClonerArrayList.clone(java.lang.Object, com.rits.cloning.Cloner, java.util.Map) @bci=47, line=23 (Compiled frame)
 - com.rits.cloning.Cloner.fastClone(java.lang.Object, java.util.Map) @bci=30, line=96 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=100, line=355 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.FastClonerArrayList.clone(java.lang.Object, com.rits.cloning.Cloner, java.util.Map) @bci=47, line=23 (Compiled frame)
 - com.rits.cloning.Cloner.fastClone(java.lang.Object, java.util.Map) @bci=30, line=96 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=100, line=355 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.FastClonerArrayList.clone(java.lang.Object, com.rits.cloning.Cloner, java.util.Map) @bci=47, line=23 (Compiled frame)
 - com.rits.cloning.Cloner.fastClone(java.lang.Object, java.util.Map) @bci=30, line=96 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=100, line=355 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.FastClonerArrayList.clone(java.lang.Object, com.rits.cloning.Cloner, java.util.Map) @bci=47, line=23 (Compiled frame)
 - com.rits.cloning.Cloner.fastClone(java.lang.Object, java.util.Map) @bci=30, line=96 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=100, line=355 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.FastClonerArrayList.clone(java.lang.Object, com.rits.cloning.Cloner, java.util.Map) @bci=47, line=23 (Compiled frame)
 - com.rits.cloning.Cloner.fastClone(java.lang.Object, java.util.Map) @bci=30, line=96 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=100, line=355 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.cloneInternal(java.lang.Object, java.util.Map) @bci=368, line=404 (Compiled frame)
 - com.rits.cloning.Cloner.deepClone(java.lang.Object) @bci=61, line=309 (Compiled frame)
 - arquitetura.representation.Architecture.deepClone() @bci=23, line=497 (Compiled frame)
 - jmetal.operators.mutation.PLAFeatureMutation.execute(java.lang.Object) @bci=109, line=862 (Compiled frame)
 - jmetal.metaheuristics.nsgaII.NSGAII.execute() @bci=321, line=129 (Compiled frame)
 - br.ufpr.inf.opla.patterns.main.NSGAII_OPLA.main(java.lang.String[]) @bci=1116, line=179 (Interpreted frame)

一段时间(一个多星期)内，我正在使用不同的参数执行相同的过程.我正在使用进化算法，因此耗时对于我的问题来说是正常的.我执行了大约120次相同的过程(带有不同的参数)，并且这是该时间中第一个挂起的过程.当前有4个进程同时运行(计算挂起的进程)，一些甚至更复杂的进程则花费更多的时间.他们正在完成，我的程序通常使用ProcessBuilder启动其他进程.我确实阅读了每个输出.挂起的进程在结束时不到一半的时间内输出了正常的日志.没有错误.另一个重要的事情是冻结过程的方法不会产生任何输出，因此我认为输出消耗没有问题.

I am executing the same process with different arguments for quite sometime now (more than a week). I am using evolutionary algorithms, so the time consuming is normal for my problem. I executed like 120 times the same process (with different arguments) and this one is the first one to hang in that time. There are currently 4 processes running simultaneously (counting the hanged one), some even more complexes that take a lot more time. They are finishing and my program is starting other processes normally using ProcessBuilder. I did read the output of each one. The hanged process outputted a normal log at less than halfway to its finish. No errors. Another important thing is that the method in which the process is frozen at generates no output, so I assume that there is no problem at the output consumption.

我的问题是:我不想终止该过程，那么有什么方法可以unhang?另外，为什么它处于IN_VM状态(在VirtualMachine中运行)并且仍然冻结?用java.lang.System.identityHashCode方法冻结进程是否正常?为什么使用0％(很少说1％)的CPU?

My questions are: I don't want to kill the process, so is there any way to unhang the process? Also, why is it at IN_VM state (Running in VirtualMachine) and is still frozen? Is it normal for a process to freeze at java.lang.System.identityHashCode method? Why is it using 0% (peaking 1% rarely) of my CPU?

如果我可以提供任何其他信息，请询问，我们很乐意在此处发布.

If I can help with any other information, please just ask and I will be glad to post it here.

谢谢.

尽管我使用多线程，但是每个线程都使用ProcessBuilder启动Process对象.因此，挂起进程是一个单独的JVM实例，仅执行一个主线程.我将输出重定向到文件，但是如前所述，该过程被挂在不产生任何输出的方法上，因此我认为输出消耗没有问题.

Although I use multithreading, each thread starts a Process object using ProcessBuilder. So, the hanging process is a separated JVM instance with only one main thread being executed. I redirect the output to a file, but as mentioned before, the process is hanged at a method that generates no output, so I assume that there is no problem with output consumption.

终止了进程.随后的过程已经开始并且正在顺利进行.

Killed the process. The subsequent process was started and is running smoothly.

推荐答案

该过程没有挂起，您只是碰巧发现它处于上述状态.您可以知道，因为有问题的线程没有像其他线程那样说已阻塞，所以它处于正常执行状态.

The process is not hanging, you just simply happen to have found it in the state posted above. You can tell because the thread in question does not say BLOCKED as the others, so it is in normal execution.

为什么不再执行该进程可能有不同的原因，但是我可以向您保证，它们都不与identityHashCode关联，因为这是一个经过充分测试的内部Java函数.

Why the process is no longer executing might have different reasons, but I can assure you that none of them is associated with identityHashCode, as this is a well-tested internal Java function.

继续:

• 比较几个挂断的JVM状态.如果始终与上面相同，则问题可能出在与哈希生成相关的某处.如果不是这样:

• Compare the JVM state of several hangups. If it is always the same as above, the issue might be somewhere associated with hash generation. If not:

发布更多相关代码，以便我们对其进行了解.如果问题不在此代码行上，则必须在其他地方(com.rits.cloning.Cloner听起来似乎是开始研究的合理点).

Post more relevant code so we can have a look at it. If the issue is not at this line of code, it has to be somewhere else (com.rits.cloning.Cloner sounds like a reasonable point to start looking).

告诉我们您要归档的内容，可能有人发现了一个错误或一个更好的方法来完全避免引起问题的所有原因.

Tell us what you are trying to archive, someone might find a bug or a better way to do it, that completely circumvents whatever is causing the issue.

这篇关于Java线程挂起而没有死锁的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！