In the case of slow receiver, sender memory doesn't get free until the MessageListener.receive() is called. ----------------------------------------------------------------------------------------------------------- Key: JGRP-1614 URL: https://issues.jboss.org/browse/JGRP-1614 Project: JGroups Issue Type: Feature Request Affects Versions: 3.2.7 Reporter: Keith Ng Assignee: Bela Ban Fix For: 3.4 In the case of slow receiver, apparently, a large chunk of memory is reserved in the sender as well as the receiver to store the un-received messages. This memory in the sender doesn't get free until the MessageListener.receive() is called. As a result, sender becomes out of memory. Anyways to discard messages in sender after the message was received at receiver even if receiver does not call MessageListener.receive() yet?