Hi,
Our prod cluster met some issues recently,
All map tasks finished successfully, but reduce task hanged.
but It's not happened on all TaskTrackers, only sometimes. we used
mapred-1.0.4
There is "0.0% reduce > copy >" forever until kill task manually.
reduce logs on the TaskTracker:
hadoop-ha
Add addtional:
Our MR version is 1.2.1, not 1.0.4
There is no useful information in the JT log.
On Fri, Jan 3, 2014 at 12:20 PM, Azuryy Yu wrote:
> Hi,
>
> Our prod cluster met some issues recently,
> All map tasks finished successfully, but reduce task hanged.
>
> but It's not happened on al
Does the Reduce task log (of attempt_201312201200_34795_r_00_0)
show any errors in trying to communicate with the various TaskTrackers
in trying to obtain the data?
On Fri, Jan 3, 2014 at 9:54 AM, Azuryy Yu wrote:
> Add addtional:
>
> Our MR version is 1.2.1, not 1.0.4
>
> There is no useful
Hi Harsh,
Thanks.
There is no any error logs for attempt_201312201200_34795_r_00_0 in the
tasktracker log. only '0.0% reduce > copy >'
I configured all hosts in all slaves and master.
This job has only one reduce. it hanged. but I configured everybody's max
job running to '1' in the Fair sch
In detail:
'and these people's job never hanged...'
these people's map and reduce tasks never hanged.
On Fri, Jan 3, 2014 at 1:46 PM, Azuryy Yu wrote:
> Hi Harsh,
> Thanks.
>
> There is no any error logs for attempt_201312201200_34795_r_00_0 in
> the tasktracker log. only '0.0% reduce > co
Hi again,
I did not mention the TaskTracker log, but the actual Task JVM's
syslog/stderr/stdout. Do those log *any* problems at all?
On Fri, Jan 3, 2014 at 11:16 AM, Azuryy Yu wrote:
> Hi Harsh,
> Thanks.
>
> There is no any error logs for attempt_201312201200_34795_r_00_0 in the
> tasktrack
Hi Harsh,
There is only three warnnings in stderr
*stderr logs*
log4j:WARN No appenders could be found for logger
(org.apache.hadoop.mapred.Child).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig
for more info.
On Fr
actuall these are all logs in the stderr, and stdout is empty
On Fri, Jan 3, 2014 at 4:12 PM, Azuryy Yu wrote:
> Hi Harsh,
> There is only three warnnings in stderr
>
> *stderr logs*
>
> log4j:WARN No appenders could be found for logger
> (org.apache.hadoop.mapred.Child).
> log4j:WARN Please i
