Modifying the stateful session bean cache

To modify the default cache timeout, edit the session-bean-cache-expiry-timeout value in the appropriate 100Custom.xml file to your topology.

If your IBM® Business Process Manager server has many users connected, the server's heap might grow to huge values. If you perform a heap dump and analyze it, you can see that a large part of the heap is occupied by WebWorkflowManager objects nested in HTTP session objects.

IBM Business Process Manager keeps a cache of stateful session beans (one session bean for each human service that a user works with). This cache is stored inside the user's HTTP session. The cache update policy removes a stateful session bean from the cache if it has not been accessed for more than one hour. If a user works with multiple human services, many stateful session beans will be in the cache for this user.

Notes:

For human services of user tasks in a business process definition (BPD) instance, the state of the stateful session bean is saved in the database with the associated task; therefore, the cache for these human services is not needed.
Human services that start directly from Process Portal (exposed as startable) do not have an associated task; therefore, the cache is not modified for these services.

To modify the default cache timeout (60 minutes), edit the appropriate 100Custom.xml file to your topology. For more information about the location of the 100Custom.xml file that must be updated, see the topic Location of configuration files.

Add the following definition to the server element:

<web-workflow-manager>
    <session-bean-cache-expiry-timeout merge="replace">timeout in minutes</session-bean-cache-expiry-timeout>
</web-workflow-manager>

An example 100Custom.xml file that sets the timeout value to 50 minutes would look like this:

<properties>
    <server>
        <web-workflow-manager>
            <session-bean-cache-expiry-timeout merge="replace">50</session-bean-cache-expiry-timeout>
        </web-workflow-manager>
    </server>
</properties>

If your processes run on a cluster, you must make this change for each cluster member.