Hi again,
Seems that was a bit overhasty.
I'm still getting freezes, but much later in the test.
I also just did a test with non-transactional sessions and it locks up
even after the producers have long stopped working. However, it seems to
be a bit different this time: The ActiveMQ server seems to be running in
some endless loop (50% CPU usage on a dual core).
There is also an error message in the server window:
ERROR queue1 - Failed to page in more queue messages
java.util.ConcurrentModificationException
at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:4
49)
at java.util.AbstractList$Itr.next(AbstractList.java:420)
at org.apache.activemq.broker.region.policy.SimpleDispatchPolicy.dispatc
h(SimpleDispatchPolicy.java:37)
at org.apache.activemq.broker.region.Queue.doDispatch(Queue.java:1053)
at org.apache.activemq.broker.region.Queue.pageInMessages(Queue.java:106
4)
at org.apache.activemq.broker.region.Queue.iterate(Queue.java:943)
at org.apache.activemq.thread.DedicatedTaskRunner.runTask(DedicatedTaskR
unner.java:98)
at org.apache.activemq.thread.DedicatedTaskRunner$1.run(DedicatedTaskRun
ner.java:36)
and probably related to this, one producer got an error:
12:07:48,199 ERROR Producer - javax.jms.JMSException: java.util.ConcurrentModifi
cationException
The processors kept on working for a few more minutes after that. So I'm not
sure
if it is related to the server hanging.
Any ideas what to do next? I'm not sure how to move on ...
Cheers,
Jürgen.
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Friday, January 18, 2008 11:24 AM
> -----Original Message-----
> From: Rob Davies [mailto:[EMAIL PROTECTED]
> Sent: Friday, January 18, 2008 8:28 AM
>
> It looks like you've hit flow control - you might want to disable it -
> see here: http://activemq.apache.org/producer-flow-control.html
Yes, that seems to be a part of the problem.
I have added this to my activemq.xml:
<policyEntry queue=">" producerFlowControl="false">
<dispatchPolicy>
<simpleDispatchPolicy/>
</dispatchPolicy>
</policyEntry>
It seems that it does not freeze anymore, but after a some time, delivery of
messages to the processors becomes much slower and messages start to pile up in
the queues.
Looks like I have to do some more investigation ...
Cheers,
Jürgen
