[ https://issues.apache.org/jira/browse/MAPREDUCE-1247?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Allen Wittenauer resolved MAPREDUCE-1247. ----------------------------------------- Resolution: Fixed > Send out-of-band heartbeat to avoid fake lost tasktracker > --------------------------------------------------------- > > Key: MAPREDUCE-1247 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-1247 > Project: Hadoop Map/Reduce > Issue Type: New Feature > Reporter: ZhuGuanyin > Assignee: ZhuGuanyin > > Currently the TaskTracker report task status to jobtracker through heartbeat, > sometimes if the tasktracker lock the tasktracker to do some cleanup job, > like remove task temp data on disk, the heartbeat thread would hang for a > long time while waiting for the lock, so the jobtracker just thought it had > lost and would reschedule all its finished maps or un finished reduce on > other tasktrackers, we call it "fake lost tasktracker", some times it doesn't > acceptable especially when we run some large jobs. So We introduce a > out-of-band heartbeat mechanism to send an out-of-band heartbeat in that case. -- This message was sent by Atlassian JIRA (v6.2#6252)