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
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 is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
