sounds like http://activemq.apache.org/producer-flow-control.html - increase your q usage limits or decrease the system usage to ensure pending message references are paged to disk. see also : http://activemq.apache.org/message-cursors.html
2009/12/11 David Delbecq <de...@oma.be> > Hello, > > we are using an activeMQ server here, as a standalone application and > used by tomcat, which connects to server using tcp:// protocol. > Sometimes, the tomcat client is stalled trying to connect to a queue, > and i have no idea why. Here is a stack dump from tomcat jvm when this > happen > > java.lang.Thread.State: WAITING (parking) > at sun.misc.Unsafe.park(Native Method) > - parking to wait for <3f543bf8> (a > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject) > at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158) > at > > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1889) > at > java.util.concurrent.ArrayBlockingQueue.take(ArrayBlockingQueue.java:317) > at > > org.apache.activemq.transport.FutureResponse.getResult(FutureResponse.java:40) > at > > org.apache.activemq.transport.ResponseCorrelator.request(ResponseCorrelator.java:80) > at > > org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1233) > at > org.apache.activemq.ActiveMQSession.send(ActiveMQSession.java:1659) > - locked <3f5425b8> (a java.lang.Object) > at > > org.apache.activemq.ActiveMQMessageProducer.send(ActiveMQMessageProducer.java:227) > at > > org.apache.activemq.ActiveMQMessageProducerSupport.send(ActiveMQMessageProducerSupport.java:241) > at be.rmi.shark.JMSEventManager.sendEvent(JMSEventManager.java:146) > > It seems that client is waiting forever to receive and answer from MQ > server. I have several threads in this situation and the only way to > unlock de situation is to kill and restart the activeMQ server. However, > the server itself does not loag any error. It looks like the srver > "forgot" to send response and client is waiting forever. Any idea what > can cause this? In current situation, we have noticed this happens when > another client is making bad connection (it connect to activeMQ queues, > receive an item but neither close connection, nor acknowledge or reject > the message). Could it be that activeMQ is stalled waiting for > acknoledge befor allowing other client to add items to queue. Should > those 2 operations be desynchronzed? > > -- > David Delbecq > ICT > Institut Royal Météorologique > Ext:557 > > > -- http://blog.garytully.com Open Source Integration http://fusesource.com
