Hi Tim & Christopher, I tried with 5.13.2 version but as you suspected, it did not solve my problem.
We don't have any wildcard subscriptions. Most of the Topics have a maximum of 8 subscriptions (Ranges between 2 and 8) and a few topics (~25-30 so far) have more than 8 (this is not fixed, it depends on no of users interested in these specific topics; the max I have seen is 40). Btw, I just realized that I have set a very low value for destination inactivity (30 secs) and hence many destinations are getting removed very early. Later when there is any message published to the same destination, it would result in destination getting created again. I will correct this by increasing this time out to appropriate values based on each destination (varies from 1 hour to 1 day) Today after upgrading to 5.13.2 version in my test env, I tried with different configurations to see if there is any improvement. In particular, I disabled journal disk sync (since many threads were waiting at KahaDB level operations) and also disabled metadata update. With these changes, the contention moved to a different level (KahaDB update index .. see attached thread dumps) ThreadDump1.txt <http://activemq.2283324.n4.nabble.com/file/n4710055/ThreadDump1.txt> ThreadDump2.txt <http://activemq.2283324.n4.nabble.com/file/n4710055/ThreadDump2.txt> I will test again by increasing the index cache size (current value is set to the default of 10000) to 100000 and see if it makes any improvement. Also histo reports showed a huge number (1393177) of org.apache.activemq.management.CountStatisticImpl instances and 1951637 instances of java.util.concurrent.locks.ReentrantLock$NonfairSync. See attached histo for complete report. histo.txt <http://activemq.2283324.n4.nabble.com/file/n4710055/histo.txt> What are these org.apache.activemq.management.CountStatisticImpl instances? Is there any way to avoid them? Thanks, Shobhana -- View this message in context: http://activemq.2283324.n4.nabble.com/ActiveMQ-with-KahaDB-as-persistent-store-becomes-very-slow-almost-unresponsive-after-creating-large-s-tp4709985p4710055.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.