I continually get tomcat in this state and can only recover by restarting tomcat from the command line. Here is the stack trace that I gathered while getting into this state, but it does not make any sense to me.
Tomcat version apache-tomcat-6.0.26 OS linux Jstack trace on tomcat hang. Tomcat is not responding, nor any webapps. Profiler will not attach Attaching to process ID 21989, please wait... Debugger attached successfully. Server compiler detected. JVM version is 10.0-b19 Deadlock Detection: No deadlocks found. Thread 15911: (state = BLOCKED) - org.netbeans.lib.profiler.server.ProfilerRuntimeMemory.getAndSendCurrentStackTrace(char, char, int, long) @bci=0, line=218 (Compiled frame) - org.netbeans.lib.profiler.server.ProfilerRuntimeObjLiveness.traceObjAlloc(java.lang.Object, char) @bci=158, line=278 (Compiled frame) - java.io.ObjectInputStream$BlockDataInputStream.<init>(java.io.ObjectInputStream, java.io.InputStream) @bci=91, line=2359 (Interpreted frame) - java.io.ObjectInputStream.<init>(java.io.InputStream) @bci=25, line=276 (Interpreted frame) - sun.rmi.server.MarshalInputStream.<init>(java.io.InputStream) @bci=2, line=107 (Interpreted frame) - sun.rmi.transport.ConnectionInputStream.<init>(java.io.InputStream) @bci=2, line=38 (Interpreted frame) - sun.rmi.transport.StreamRemoteCall.getInputStream() @bci=32, line=115 (Interpreted frame) - sun.rmi.transport.Transport.serviceCall(java.rmi.server.RemoteCall) @bci=1, line=124 (Interpreted frame) - sun.rmi.transport.tcp.TCPTransport.handleMessages(sun.rmi.transport.Connection, boolean) @bci=217, line=541 (Compiled frame) - sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0() @bci=821, line=810 (Interpreted frame) - sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run() @bci=58, line=652 (Interpreted frame) - java.util.concurrent.ThreadPoolExecutor$Worker.runTask(java.lang.Runnable) @bci=59, line=885 (Interpreted frame) - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=28, line=907 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 12244: (state = BLOCKED) - org.netbeans.lib.profiler.server.ProfilerRuntimeMemory.getAndSendCurrentStackTrace(char, char, int, long) @bci=0, line=218 (Compiled frame) - org.netbeans.lib.profiler.server.ProfilerRuntimeObjLiveness.traceObjAlloc(java.lang.Object, char) @bci=158, line=278 (Compiled frame) - java.io.ObjectInputStream$BlockDataInputStream.<init>(java.io.ObjectInputStream, java.io.InputStream) @bci=91, line=2359 (Interpreted frame) - java.io.ObjectInputStream.<init>(java.io.InputStream) @bci=25, line=276 (Interpreted frame) - sun.rmi.server.MarshalInputStream.<init>(java.io.InputStream) @bci=2, line=107 (Interpreted frame) - sun.rmi.transport.ConnectionInputStream.<init>(java.io.InputStream) @bci=2, line=38 (Interpreted frame) - sun.rmi.transport.StreamRemoteCall.getInputStream() @bci=32, line=115 (Interpreted frame) - sun.rmi.transport.Transport.serviceCall(java.rmi.server.RemoteCall) @bci=1, line=124 (Interpreted frame) - sun.rmi.transport.tcp.TCPTransport.handleMessages(sun.rmi.transport.Connection, boolean) @bci=217, line=541 (Compiled frame) - sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0() @bci=821, line=810 (Interpreted frame) - sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run() @bci=58, line=652 (Interpreted frame) - java.util.concurrent.ThreadPoolExecutor$Worker.runTask(java.lang.Runnable) @bci=59, line=885 (Interpreted frame) - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=28, line=907 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 22760: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - java.util.TimerThread.mainLoop() @bci=28, line=483 (Interpreted frame) - java.util.TimerThread.run() @bci=1, line=462 (Interpreted frame) Thread 3343: (state = BLOCKED) - org.netbeans.lib.profiler.server.ProfilerRuntimeMemory.getAndSendCurrentStackTrace(char, char, int, long) @bci=0, line=218 (Compiled frame) - org.netbeans.lib.profiler.server.ProfilerRuntimeObjLiveness.traceObjAlloc(java.lang.Object, char) @bci=158, line=278 (Compiled frame) - java.lang.String.valueOf(char[]) @bci=12, line=2841 (Interpreted frame) - java.lang.Thread.getName() @bci=4, line=1061 (Interpreted frame) - org.apache.catalina.connector.CoyoteAdapter.service(org.apache.coyote.Request, org.apache.coyote.Response) @bci=120, line=295 (Interpreted frame) - org.apache.coyote.http11.Http11Processor.process(java.net.Socket) @bci=468, line=852 (Interpreted frame) - org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(java.net.Socket) @bci=82, line=588 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=41, line=489 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 3255: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 3202: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 2805: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 2721: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 2372: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 2143: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 1621: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Interpreted frame) - java.lang.Object.wait() @bci=2, line=485 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=458 (Interpreted frame) - org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=484 (Interpreted frame) - java.lang.Thread.run() @bci=11, line=619 (Interpreted frame) Thread 531: (state = BLOCKED) - org.netbeans.lib.profiler.server.ProfilerRuntimeMemory.writeObjGCEvent(long) @bci=12, line=363 (Compiled frame) - org.netbeans.lib.profiler.server.ProfilerRuntimeObjLiveness.signalObjGC(org.netbeans.lib.profiler.server.ProfilerRuntimeObjLiveness$ProfilerRuntimeObjLivenessWeakRef) @bci=13, line=233 (Compiled frame) - org.netbeans.lib.profiler.server.ProfilerRuntimeObjLiveness$ReferenceManagerThread.run() @bci=25, line=92 (Compiled frame)
