[jboss-jira] [JBoss JIRA] Updated: (JGRP-1282) Race condition in FLUSH when master leaves cluster

Race condition in FLUSH when master leaves cluster -------------------------------------------------- Key: JGRP-1282 URL: https://issues.jboss.org/browse/JGRP-1282 Project: JGroups Issue Type: Bug Affects Versions: 2.6.16 Reporter: Dennis Reed Assignee: Vladimir Blagojevic Fix For: 2.6.19, 2.11.2, 2.12 There's a race condition in FLUSH when the master node is leaving the cluster, that can cause the master to not send a new view (with a new master) before leaving. The FLUSH is started when GMS sends down an Event.SUSPEND. FLUSH.down calls FLUSH.startFlush, which calls FLUSH.onSuspend. onSuspend sends a START_FLUSH message down. In the working case, the local node gets the START_FLUSH first. FLUSH.up calls FLUSH.handleStartFlush, which calls FLUSH.onStartFlush. onStartFlush sets the member variable "flushMembers". Then the other nodes reply to the START_FLUSH with a FLUSH_COMPLETED. FLUSH.up calls FLUSH.onFlushCompleted. onFlushCompleted checks "flushMembers" against the list of replies. If they match (and flushMembers is not null), the flush completes. But in the non-working case, the FLUSH_COMPLETED from the other nodes is processed before the local START_FLUSH. In this case, flushMembers has not been set, and onFlushCompleted does nothing, expecting more replies (which never come). I believe this will only be triggered when the master is leaving, because it does not include itself in the FLUSH. If it was a flush member, there would be a FLUSH_COMPLETED reply from itself to trigger setting flushMembers at some point.