-Re: Running map tasks after all reduces have finished
Harsh J 2012-08-23, 10:08
What version/distribution of Hadoop are you noticing this on?
On Thu, Aug 23, 2012 at 2:55 PM, Jan Lukavský
<[EMAIL PROTECTED]> wrote:
> Hi all,
> we are seeing strange behaviour of JobTracker in the following scenario:
> - job finishes map phase and starts reduce
> - after the shuffle phase of all reducers we loose a tasktracker, that
> doesn't run any reducer - so all remaining reducers are still running in the
> reduce phase
> - map tasks that were running on the lost tasktracker are rescheduled
> - reduces may finish earlier than the rescheduled map tasks and so the job
> is blocked waiting for the maps to finish, although their output is simple
> Is this behaviour a bug or feature? :) I haven't found any JIRA that would
> describe it, if there exists one can anyone point me out?