Memory leak in JS7 Controller branch 2.5

Current Situation

• In a Controller cluster without workflows being executed the memory is eaten. Approximately 1,5 MB per day. Memory consumption is stable for about 5 minutes. Then memory will be eaten (~50KB). The Controller will crash when the assigned Java heap space is consumed.
• The root cause of the error is the fact that in case that no events are created from workflow execution, then memory is consumed from repeated tries to checkc the event queue. The error will not materialise if some workflow is executed every few days.
• Command to measure memory consumption (memory usage will displayed with column MU):

  #/bin/bash
  jstat -gc `cat /home/controller/var/logs/controller.pid` 60000 | gawk '{print strftime("%m/%d/%Y %H:%M:%S"), $0; fflush()}' >> /home/cont_m_jstat.txt
  

Desired Behavior

• No memory should be eaten by the Controller.