AEM_OPEN_CRXSession

Issue :

• The system gets slower and slower
• From time to time the system runs out of memory (after a few hours, days, or weeks - depending on the severity)

Cause :

• If an application opens CRXSessions explicitely, make sure the proper closure of these sessions. 
• If not, such sessions will not be subject of garbage collection and thus will stay in memory, causing above listed symptoms.
• Each CRXSession creates and maintains its own set of caches which adds to the overall resource consumption.

Analysis :

• Run following commands to determine the overall number of current CRXSessions held in memory:

                          jmap -histo:live | grep CRXSessionImpl

         The second column of the output is the instance count, which means that that many sessions are not closed (and             actually reside in-memory). 

          If this number is significantly higher than 100, then there is a problem with CRXSessions in your application.

• To see how many CRXSession objects are held in memory including those waiting to be garbage collected, run the command below:

                         jmap -histo | grep CRXSessionImpl

      This tells you how many session objects are in memory which are live or haven't been garbage collected yet. 

Conclusion:

• You can force a jvm full garbage collection by going to http://:/system/console/memoryusageand clicking the "Run Garbage Collector" button.
•   After doing this, you can run the above command again a few times to see how quickly the number of session objects increases.