Log Saver process throws OOM exception. 

Currently there is no limit on the number of events that can be in the in memory messageTable which could cause the Log Saver to throw OOM.

Fix is to maintain the in memory window of events containing fixed number of buckets (controlled by config variable "log.saver.event.max.inmemory.buckets") in the messageTable. 

If the in-coming event falls out of the window then sleep till the window moves forward and include the event.  
Reducing the max buckets, and bucket interval in test will result in reduction in the amount of time required to sleep over here. It is generally not a good idea to sleep for few seconds in a test. It will slow down the execution of tests. See if this can be reduced to a few ms.