,I am not able to locate where "jbpm.cfg.xml" file resides in alfresco.war as i need to update "<field name="idleInterval"><int value="5000" /></field>" to update workflow?
For reference, it's located in the alfresco-repository.jar. However, a better way to override is to copy (and edit) the file to your extension directory and then create a custom-workflow-context.xml which overrides the Spring bean and points to your custom copy.