Hi Gaurav, thank you for your reply. Xms and xmx are both set to 1G (CMS collector is used and explicit GC disabled, nothing else), and the system usage is as follows:
<systemUsage> <systemUsage> <memoryUsage> <memoryUsage limit="500 mb" /> </memoryUsage> <storeUsage> <storeUsage limit="1 gb" /> </storeUsage> <tempUsage> <tempUsage limit="200 mb" /> </tempUsage> </systemUsage> </systemUsage> However I'm not sure this could be GC related for two reasons: 1. Producers which are reusing their jms connections do not experience any slowness, they are completely impact free. I guess a stop the world GC would slow them down as well. 2. According to JConsole the total GC time is very low. Seconds on ParNew and even less on CMS. While the connection slowdowns can be tens of seconds. We are using tcp transport, the RAM on the host running it is tens of gigabytes, but it is of course running other applications as well. The load average on the host is normal. And yes the slowness seems to occur more frequently when a higher number of large messages are being sent, but I couldn't reproduce it yet in the development environment with our load tests. -- View this message in context: http://activemq.2283324.n4.nabble.com/Slow-starting-activemq-connection-tp4661562p4661706.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.