Help with Java crashes

[antonio]

We've just moved to a Debian Linux server. Servoy runs fine for a day or so then will fall over every few minutes in quick succession, with the attached error (or similar) in the hs_err_pid log.

I have 4G of RAM on the server and only use 1G for servoy with this startup - our host has added some tweaks to the settings in an attempt to get it more stable.
We are running 32 but java for compatibility with third party jar files.

Code: Select all

#!/bin/sh

exec /usr/lib/jvm/ia32-java-6-sun/jre/bin/java -Djava.awt.headless=true -Xmx1024m -Xms1024m -XX:MaxPermSize=320m -XX:+PrintGCDetails -XX:+UseCMSCompactAtFullCollection -Xss128k -XX:MinHeapFreeRatio=25 -XX:MaxHeapFreeRatio=30 -XX:MaxNewSize=512m -XX:+UseParallelGC -XX:ParallelGCThreads=4 -XX:ErrorFile=/home/servoy/java_crash_logs/hs_err_pid%p.log -classpath .:lib/ohj-jewt.jar:lib/MRJAdapter.jar:lib/compat141.jar:lib/commons-codec.jar:lib/commons-httpclient.jar:lib/activation.jar:lib/antlr.jar:lib/commons-collections.jar:lib/commons-dbcp.jar:lib/commons-fileupload-1.2.1.jar:lib/commons-io-1.4.jar:lib/commons-logging.jar:lib/commons-pool.jar:lib/dom4j.jar:lib/help.jar:lib/jabsorb.jar:lib/hibernate3.jar:lib/j2db.jar:lib/j2dbdev.jar:lib/jdbc2_0-stdext.jar:lib/jmx.jar:lib/jndi.jar:lib/js.jar:lib/jta.jar:lib/BrowserLauncher2.jar:lib/jug.jar:lib/log4j.jar:lib/mail.jar:lib/ohj-jewt.jar:lib/oracle_ice.jar:lib/server-bootstrap.jar:lib/servlet-api.jar:lib/wicket-extentions.jar:lib/wicket.jar:lib/wicket-calendar.jar:lib/slf4j-api.jar:lib/slf4j-log4j.jar:lib/joda-time.jar:lib/rmitnl.jar:lib/networktnl.jar com.servoy.j2db.server.ApplicationServer "$@"


I've been watching the amount of free RAM reported in the servoy admin pages and there's always ample, so I'm at a loss to know why java is dying with the out of error message. It isn't related to the number of clients, we can have 30 with no probs

System Information
Heap memory: allocated=994240K, used=173226K, max=994240K
None Heap memory: allocated=72096K, used=71876K, max=376832K

Stackdump

Code: Select all

Current time: Thu May 03 22:21:19 EST 2012

Server Information
Servoy version 5.2.11 -build 1022
Port used by RMI Registry: 1099
Repository version 38

Current time: Thu May 03 22:21:19 EST 2012

Uptime:  9 minutes 31 seconds

JDK Information
java.vm.name=Java HotSpot(TM) Server VM
java.version=1.6.0_26
java.vm.info=mixed mode
java.vm.vendor=Sun Microsystems Inc.

Operating System Information
os.name=Linux
os.version=2.6.32-5-amd64
os.arch=i386

System Information
Heap memory: allocated=1028096K, used=130231K, max=1028096K
None Heap memory: allocated=75136K, used=74926K, max=376832K

Thread: Image Fetcher 0, state: TIMED_WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  sun.awt.image.ImageFetcher.nextImage(ImageFetcher.java:114)
  sun.awt.image.ImageFetcher.fetchloop(ImageFetcher.java:167)
  sun.awt.image.ImageFetcher.run(ImageFetcher.java:136)

Thread: Timer-11, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: Timer-10, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: Timer-9, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: TaskExecuter[3], state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  com.servoy.j2db.util.TaskExecuter.run(TaskExecuter.java:70)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-7-thread-2, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:399)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: Timer-8, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: pool-9-thread-1, state: WAITING, total cpu time: 20.0ms, total user time: 20.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:399)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: TaskExecuter[2], state: WAITING, total cpu time: 20.0ms, total user time: 10.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  com.servoy.j2db.util.TaskExecuter.run(TaskExecuter.java:70)
  java.lang.Thread.run(Thread.java:662)

Thread: Timer-7, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: Timer-6, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: Timer-5, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: pool-8-thread-1, state: WAITING, total cpu time: 10.0ms, total user time: 10.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:399)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: Timer-4, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: TaskExecuter[1], state: WAITING, total cpu time: 30.0ms, total user time: 30.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  com.servoy.j2db.util.TaskExecuter.run(TaskExecuter.java:70)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-7, state: WAITING, total cpu time: 550.0ms, total user time: 530.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:423)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:449)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-5-thread-1, state: WAITING, total cpu time: 10.0ms, total user time: 0.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:399)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: TaskExecuter[0], state: WAITING, total cpu time: 40.0ms, total user time: 40.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  com.servoy.j2db.util.TaskExecuter.run(TaskExecuter.java:70)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-1-thread-3, state: WAITING, total cpu time: 50.0ms, total user time: 30.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.DelayQueue.take(DelayQueue.java:160)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:609)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:602)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-1-thread-2, state: WAITING, total cpu time: 60.0ms, total user time: 50.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.DelayQueue.take(DelayQueue.java:160)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:609)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:602)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-6, state: WAITING, total cpu time: 70.0ms, total user time: 70.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:423)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:449)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-5, state: WAITING, total cpu time: 5100.0ms, total user time: 4950.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:423)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:449)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-4, state: WAITING, total cpu time: 25020.0ms, total user time: 24440.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:423)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:449)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-3, state: RUNNABLE, total cpu time: 12520.0ms, total user time: 12300.0ms
  sun.management.ThreadImpl.getThreadInfo1(Native Method)
  sun.management.ThreadImpl.getThreadInfo(ThreadImpl.java:154)
  sun.management.ThreadImpl.getThreadInfo(ThreadImpl.java:121)
  com.servoy.j2db.server.servlets.ConfigServlet.Zt(ConfigServlet.java:215)
  com.servoy.j2db.server.servlets.ConfigServlet.service(ConfigServlet.java:3902)
  javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
  org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
  org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
  org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
  org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
  org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
  org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
  org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:567)
  org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
  org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
  org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
  org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-2, state: WAITING, total cpu time: 16300.0ms, total user time: 15970.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:423)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:449)
  java.lang.Thread.run(Thread.java:662)

Thread: Timer-1, state: TIMED_WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.util.TimerThread.mainLoop(Timer.java:509)
  java.util.TimerThread.run(Timer.java:462)

Thread: scheduler_QuartzSchedulerThread, state: TIMED_WAITING, total cpu time: 10.0ms, total user time: 10.0ms
  java.lang.Object.wait(Native Method)
  org.quartz.core.QuartzSchedulerThread.run(QuartzSchedulerThread.java:411)

Thread: scheduler_Worker-1, state: TIMED_WAITING, total cpu time: 50.0ms, total user time: 20.0ms
  java.lang.Object.wait(Native Method)
  org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:543)

Thread: DestroyJavaVM, state: RUNNABLE, total cpu time: 5470.0ms, total user time: 5130.0ms

Thread: http-8080-1, state: WAITING, total cpu time: 520.0ms, total user time: 480.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:423)
  org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:449)
  java.lang.Thread.run(Thread.java:662)

Thread: http-8080-Acceptor-0, state: RUNNABLE, total cpu time: 100.0ms, total user time: 80.0ms
  java.net.PlainSocketImpl.socketAccept(Native Method)
  java.net.PlainSocketImpl.accept(PlainSocketImpl.java:408)
  java.net.ServerSocket.implAccept(ServerSocket.java:462)
  java.net.ServerSocket.accept(ServerSocket.java:430)
  org.apache.tomcat.util.net.DefaultServerSocketFactory.acceptSocket(DefaultServerSocketFactory.java:61)
  org.apache.tomcat.util.net.JIoEndpoint$Acceptor.run(JIoEndpoint.java:317)
  java.lang.Thread.run(Thread.java:662)

Thread: ContainerBackgroundProcessor[StandardEngine[Catalina]], state: TIMED_WAITING, total cpu time: 20.0ms, total user time: 20.0ms
  java.lang.Thread.sleep(Native Method)
  org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1579)
  java.lang.Thread.run(Thread.java:662)

Thread: Timer-0, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.util.TimerThread.mainLoop(Timer.java:483)
  java.util.TimerThread.run(Timer.java:462)

Thread: Java2D Disposer, state: WAITING, total cpu time: 10.0ms, total user time: 10.0ms
  java.lang.Object.wait(Native Method)
  java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:118)
  java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:134)
  sun.java2d.Disposer.run(Disposer.java:127)
  java.lang.Thread.run(Thread.java:662)

Thread: ModificationWatcher Task, state: TIMED_WAITING, total cpu time: 260.0ms, total user time: 240.0ms
  java.lang.Thread.sleep(Native Method)
  org.apache.wicket.util.time.Duration.sleep(Duration.java:445)
  org.apache.wicket.util.thread.Task$1.run(Task.java:130)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-3-thread-1, state: TIMED_WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:198)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2025)
  java.util.concurrent.DelayQueue.take(DelayQueue.java:164)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:609)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:602)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: GC Daemon, state: TIMED_WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  sun.misc.GC$Daemon.run(GC.java:100)

Thread: RMI Reaper, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:118)
  java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:134)
  sun.rmi.transport.ObjectTable$Reaper.run(ObjectTable.java:333)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-1-thread-1, state: WAITING, total cpu time: 690.0ms, total user time: 620.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.DelayQueue.take(DelayQueue.java:160)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:609)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:602)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: RMI TCP Accept-1099, state: WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
  java.util.concurrent.ArrayBlockingQueue.take(ArrayBlockingQueue.java:317)
  com.servoy.j2db.rmi.ServerTwoWaySocketFactory$TwoWayServerSocket.accept(ServerTwoWaySocketFactory.java:578)
  sun.rmi.transport.tcp.TCPTransport$AcceptLoop.executeAcceptLoop(TCPTransport.java:369)
  sun.rmi.transport.tcp.TCPTransport$AcceptLoop.run(TCPTransport.java:341)
  java.lang.Thread.run(Thread.java:662)

Thread: 2 way Server Acceptor, state: RUNNABLE, total cpu time: 0.0ms, total user time: 0.0ms
  java.net.PlainSocketImpl.socketAccept(Native Method)
  java.net.PlainSocketImpl.accept(PlainSocketImpl.java:408)
  java.net.ServerSocket.implAccept(ServerSocket.java:462)
  com.servoy.j2db.rmi.ServerTwoWaySocketFactory$TwoWayServerSocket.run(ServerTwoWaySocketFactory.java:601)
  java.lang.Thread.run(Thread.java:662)

Thread: pool-2-thread-1, state: TIMED_WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  sun.misc.Unsafe.park(Native Method)
  java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:198)
  java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2025)
  java.util.concurrent.DelayQueue.take(DelayQueue.java:164)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:609)
  java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:602)
  java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:947)
  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
  java.lang.Thread.run(Thread.java:662)

Thread: PingScanner, state: TIMED_WAITING, total cpu time: 0.0ms, total user time: 0.0ms
  java.lang.Object.wait(Native Method)
  com.servoy.j2db.dataprocessing.Zn.run(Zn.java:44)
  java.lang.Thread.run(Thread.java:662)

Thread: MessageScheduler, state: TIMED_WAITING, total cpu time: 10.0ms, total user time: 10.0ms
  java.lang.Object.wait(Native Method)
  com.servoy.j2db.dataprocessing.Zp.run(Zp.java:44)
  java.lang.Thread.run(Thread.java:662)

Thread: MessagePreHandler, state: WAITING, total cpu time: 20.0ms, total user time: 10.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  com.servoy.j2db.dataprocessing.ClientMessagePreQueueHandler.run(ClientMessagePreQueueHandler.java:2)
  java.lang.Thread.run(Thread.java:662)

Thread: Signal Dispatcher, state: RUNNABLE, total cpu time: 0.0ms, total user time: 0.0ms

Thread: Finalizer, state: WAITING, total cpu time: 90.0ms, total user time: 90.0ms
  java.lang.Object.wait(Native Method)
  java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:118)
  java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:134)
  java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)

Thread: Reference Handler, state: WAITING, total cpu time: 30.0ms, total user time: 30.0ms
  java.lang.Object.wait(Native Method)
  java.lang.Object.wait(Object.java:485)
  java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)



I'd really appreciate some pointers on where to go looking for the source of this intermittent problem.

[Andrei Costescu]

Take a look at this Java bug report. It is consistent with the Java version you are using.

A workaround that is suggested in there is using "-XX:-DoEscapeAnalysis".
Also try updating Java to a newer version where that bug is fixed is order not to disable that optimization.

[antonio]

Thanks for that, we found that the problem disappeared after upgrading to java.version=1.6.0_29