无法获得线程转储？我的应用程序阻止的任何想法？

Question

我有一个基本的Java服务器应用程序,它有100个工作线程,可以在URL上执行简单的HEAD请求.我正在使用HttpClient 4.x.

几分钟后,我的程序冻结了几分钟,我无法弄清楚原因.查看可视vm监视器报告的屏幕截图.你可以看到它扁平化.在这段时间里,我无法获得良好的线程转储,视觉vm只是冻结,直到它被解锁.有没有人有任何想法,我可以做什么来尝试开始调试这个人？

Visual VM:http://tinypic.com/view.php？pic = 2i915bs&s = 7

这是我在冻结时尝试获取jstack转储时的输出:

jstack -F 4325 
Attaching to process ID 4325, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 16.3-b01
Deadlock Detection:

No deadlocks found.

Thread 4557: (state = BLOCKED)
Error occurred during stack walking:
sun.jvm.hotspot.debugger.DebuggerException: sun.jvm.hotspot.debugger.DebuggerException: get_thread_regs failed for a lwp
    at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal$LinuxDebuggerLocalWorkerThread.execute(LinuxDebuggerLocal.java:152)
    at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.getThreadIntegerRegisterSet(LinuxDebuggerLocal.java:466)
    at sun.jvm.hotspot.debugger.linux.LinuxThread.getContext(LinuxThread.java:65)
    at sun.jvm.hotspot.runtime.linux_amd64.LinuxAMD64JavaThreadPDAccess.getCurrentFrameGuess(LinuxAMD64JavaThreadPDAccess.java:92)
    at sun.jvm.hotspot.runtime.JavaThread.getCurrentFrameGuess(JavaThread.java:256)
    at sun.jvm.hotspot.runtime.JavaThread.getLastJavaVFrameDbg(JavaThread.java:218)
    at sun.jvm.hotspot.tools.StackTrace.run(StackTrace.java:76)
    at sun.jvm.hotspot.tools.StackTrace.run(StackTrace.java:45)
    at sun.jvm.hotspot.tools.JStack.run(JStack.java:60)
    at sun.jvm.hotspot.tools.Tool.start(Tool.java:221)
    at sun.jvm.hotspot.tools.JStack.main(JStack.java:86)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at sun.tools.jstack.JStack.runJStackTool(JStack.java:118)
    at sun.tools.jstack.JStack.main(JStack.java:84)
Caused by: sun.jvm.hotspot.debugger.DebuggerException: get_thread_regs failed for a lwp
    at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.getThreadIntegerRegisterSet0(Native Method)
    at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal.access$800(LinuxDebuggerLocal.java:51)
    at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal$1GetThreadIntegerRegisterSetTask.doit(LinuxDebuggerLocal.java:460)
    at sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal$LinuxDebuggerLocalWorkerThread.run(LinuxDebuggerLocal.java:127)

Answer 1

很可能是由于内存使用过多导致GC。将参数添加到java：

-verbosegc -XX:+PrintGCDetails

看看你是否注意到输出/日志中有任何明显的东西