WLST Hangs Up Because of Java VM ClassLoader Deadlock

APPLIES TO:

Oracle WebLogic Server - Version 10.0 to 10.3.6
Information in this document applies to any platform.

SYMPTOMS

The WLST connect command hangs up because of a Java VM ClassLoader deadlock issue. You will see the following thread stacks in the thread dumps. The "ExecuteThread: '3' for queue: 'default'" thread waiting to lock <6a04a378>. The "main" thread has lock <6a04a378>. And "main" thread waiting to lock <69a506c0>. The "ExecuteThread: '3' for queue: 'default'" thread has lock <69a506c0>.

"ExecuteThread: '3' for queue: 'default'" daemon prio=7 tid=0049b500 nid=17 lwp_id=4192481 waiting for monitor entry [358ff000..35900d50]
    at java.lang.ClassLoader.getPackage(ClassLoader.java:1441)
    - waiting to lock <6a04a378> (a java.util.HashMap)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:220)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    - locked <69a506c0> (a sun.misc.Launcher$AppClassLoader)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
    - locked <69a506c0> (a sun.misc.Launcher$AppClassLoader)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
    - locked <69a506c0> (a sun.misc.Launcher$AppClassLoader)
    at weblogic.timers.internal.TimerImpl.recordExpirationTime(TimerImpl.java:347)
    at weblogic.timers.internal.TimerImpl.run(TimerImpl.java:272)
    at weblogic.work.ExecuteRequestAdapter.execute(ExecuteRequestAdapter.java:21)
    at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:145)
    at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:117)

...

"main" prio=7 tid=004999e0 nid=1 lwp_id=-1 waiting for monitor entry [7fffa000..7fffd6e8]
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:261)
    - waiting to lock <69a506c0> (a sun.misc.Launcher$AppClassLoader)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
    at java.net.URL.getURLStreamHandler(URL.java:1141)
    at java.net.URL.<init>(URL.java:393)
    at java.net.URL.<init>(URL.java:283)
    at java.net.URL.<init>(URL.java:306)
    at sun.net.www.ParseUtil.fileToEncodedURL(ParseUtil.java:261)
    at java.lang.Package$1.run(Package.java:514)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.lang.Package.defineSystemPackage(Package.java:505)
    at java.lang.Package.getSystemPackage(Package.java:481)
    - locked <69a63cb8> (a java.util.HashMap)
    at java.lang.ClassLoader.getPackage(ClassLoader.java:1447)
    - locked <6a05d300> (a java.util.HashMap)
    at java.lang.ClassLoader.getPackage(ClassLoader.java:1445)
    - locked <6a04a378> (a java.util.HashMap)
    at java.lang.ClassLoader.getPackage(ClassLoader.java:1445)
    - locked <69a54780> (a java.util.HashMap)
    at java.lang.ClassLoader.getPackage(ClassLoader.java:1445)
    - locked <69d566e0> (a java.util.HashMap)
    at weblogic.utils.classloaders.GenericClassLoader.definePackage(GenericClassLoader.java:442)
    at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericClassLoader.java:335)
    at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:291)
    - locked <69cddb50> (a weblogic.utils.classloaders.GenericClassLoader)
    at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:259)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    - locked <69cddb50> (a weblogic.utils.classloaders.GenericClassLoader)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
    at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:179)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
    - locked <69cddb50> (a weblogic.utils.classloaders.GenericClassLoader)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:246)
    at weblogic.utils.classloaders.GenericClassLoader.defineCodeGenClass(GenericClassLoader.java:503)
    at weblogic.utils.classfile.utils.CodeGenerator.generateClass(CodeGenerator.java:73)
    at weblogic.rmi.internal.StubGenerator.hotCodeGenClass(StubGenerator.java:775)
    at weblogic.rmi.internal.StubGenerator.getStubClass(StubGenerator.java:759)
    at weblogic.rmi.internal.StubGenerator.generateStub(StubGenerator.java:786)
    at weblogic.rmi.internal.StubGenerator.generateStub(StubGenerator.java:779)
    at weblogic.rmi.extensions.StubFactory.getStub(StubFactory.java:76)
    at weblogic.rmi.internal.StubInfo.resolveObject(StubInfo.java:214)
    at weblogic.rmi.internal.StubInfo.readResolve(StubInfo.java:208)
    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:585)
    at java.io.ObjectStreamClass.invokeReadResolve(ObjectStreamClass.java:1033)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1728)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:348)
    at weblogic.utils.io.ChunkedObjectInputStream.readObject(ChunkedObjectInputStream.java:195)
    at weblogic.rjvm.MsgAbbrevInputStream.readObject(MsgAbbrevInputStream.java:565)
    at weblogic.utils.io.ChunkedObjectInputStream.readObject(ChunkedObjectInputStream.java:191)
    at weblogic.rmi.internal.ObjectIO.readObject(ObjectIO.java:62)
    at weblogic.rjvm.ResponseImpl.unmarshalReturn(ResponseImpl.java:227)
    at weblogic.rmi.internal.BasicRemoteRef.invoke(BasicRemoteRef.java:224)
    at weblogic.management.remote.iiop.IIOPServerImpl_1001_WLStub.newClient(Unknown Source)
    at weblogic.management.remote.common.RMIServerWrapper.newClient(ClientProviderBase.java:234)
    at javax.management.remote.rmi.RMIConnector.getConnection(RMIConnector.java:2238)
    at javax.management.remote.rmi.RMIConnector.connect(RMIConnector.java:271)
    - locked <65b39430> (a weblogic.management.remote.common.WLSRMIConnector)
    at weblogic.management.remote.common.WLSRMIConnector.doConnect(WLSRMIConnector.java:146)
    - locked <65b39430> (a weblogic.management.remote.common.WLSRMIConnector)
    at weblogic.management.remote.common.WLSRMIConnector.access$100(WLSRMIConnector.java:24)
    at weblogic.management.remote.common.WLSRMIConnector$2.run(WLSRMIConnector.java:134)
    at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363)
    at weblogic.security.service.SecurityManager.runAs(Unknown Source)
    at weblogic.security.Security.runAs(Security.java:61)
    at weblogic.management.remote.common.WLSRMIConnector.connect(WLSRMIConnector.java:132)
    - locked <65b39430> (a weblogic.management.remote.common.WLSRMIConnector)
    at javax.management.remote.JMXConnectorFactory.connect(JMXConnectorFactory.java:248)
    at weblogic.management.scripting.WLSTHelper.lookupMBeanServerConnection(WLSTHelper.java:656)
    at weblogic.management.scripting.WLSTHelper.initRuntimeServerConnection(WLSTHelper.java:376)
    at weblogic.management.scripting.WLSTHelper.initConnections(WLSTHelper.java:305)
    at weblogic.management.scripting.WLSTHelper.connect(WLSTHelper.java:201)
    at weblogic.management.scripting.WLScriptContext.connect(WLScriptContext.java:60)
    at weblogic.management.scripting.utils.WLSTUtil.initializeOnlineWLST(WLSTUtil.java:121)
    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:585)
    at org.python.core.PyReflectedFunction.__call__(PyReflectedFunction.java:160)
    at org.python.core.PyMethod.__call__(PyMethod.java:96)
    at org.python.core.PyObject.__call__(PyObject.java:248)
    at org.python.core.PyObject.invoke(PyObject.java:2016)
    at org.python.pycode._pyx6.connect$1(<iostream>:16)
    at org.python.pycode._pyx6.call_function(<iostream>)
    at org.python.core.PyTableCode.call(PyTableCode.java:208)
    at org.python.core.PyTableCode.call(PyTableCode.java:404)
    at org.python.core.PyFunction.__call__(PyFunction.java:184)
    at org.python.pycode._pyx18.f$0(/opt/bea/user_projects/domains/test-domain/shutdown.py:1)
    at org.python.pycode._pyx18.call_function(/opt/bea/user_projects/domains/test-domain/shutdown.py)
    at org.python.core.PyTableCode.call(PyTableCode.java:208)
    at org.python.core.PyCode.call(PyCode.java:14)
    at org.python.core.Py.runCode(Py.java:1135)
    at org.python.util.PythonInterpreter.execfile(PythonInterpreter.java:167)
    at weblogic.management.scripting.WLST.main(WLST.java:106)
    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:585)
    at weblogic.WLST.main(WLST.java:29)

CAUSE

This is a Java VM issue which is documented at JDK-4670071 : java.lang.ClassLoader.loadClassInternal(String) is too restrictive.

The Problem was fixed by the following versions.

  • Java 7 GA
  • Java 6 update 18

This issue does not occur on Java 7 and higher.

上一篇:Android百度地图之显示地图


下一篇:UGUI背包系统