APM MQMonitor agent OutOfMemory

Document ID : KB000106260
Last Modified Date : 13/07/2018
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Issue:
We are using the Websphere MQ Agent v10.5.2.52 and we noticed that we got java.lang.OutOfMemoryError exceptions.
 
Cause:
This was relating to specific configuration in the environment, which created large "com.ibm.mq.jmqi.system.JmqiComponentTls" objects in memory which in turn were holding onto huge "security policy" objects.
It is not a leak and specific to the configuration in the environment.
Resolution:
The heap of the MQMonitor process should be increased, to a minimum 1.5GB.
This is configured in startMQMonitor.sh

Look for the section where minimum and maximum heap are configured
 
-Xms64m -Xmx512m

and increase the maximum
 
-Xms64m -Xmx1536m

Make sure you are using a 64-bit JRE if you want to allocate larger amounts of heap.