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From Bharati <bharati.ad...@mparallelo.com>
Subject Re: TaskID
Date Thu, 25 Apr 2013 17:08:30 GMT
Thanks,
I will try it and let you know if I run into problems. 

Sent from my iPhone

On Apr 25, 2013, at 9:20 AM, Chris Nauroth <cnauroth@hortonworks.com> wrote:

> Hi Bharati,
> 
> Your mapper class implementation methods have access to a MapContext:
> 
> http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapreduce/MapContext.html
> 
> This is a subclass of TaskAttemptContext:
> 
> http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapreduce/TaskAttemptContext.html
> 
> You can use the TaskAttemptContext to call getTaskAttemptId and retrieve a TaskAttemptID
object:
> 
> http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapreduce/TaskAttemptID.html
> 
> A task attempt ID consists of the task ID + an attempt number.  Note that task ID alone
is not guaranteed to be unique across execution of the whole job.  Due to speculative execution
or transient task failures, multiple attempts of the same task can run, and they'll all have
the same task ID.  The task ID + attempt number is guaranteed to be unique within the job.
> 
> BTW, it's pretty much the same process for a reducer too, except you're working with
a ReduceContext instead of a MapContext.
> 
> Hope this helps,
> --Chris
> 
> 
> 
> 
> 
> 
> 
> On Thu, Apr 25, 2013 at 8:45 AM, Bharati <bharati.adkar@mparallelo.com> wrote:
>> Hi Folks,
>> 
>> I need to find the task ID of the map task.
>> Please send me any ideas or suggestions.
>> 
>> Thanks,
>> Bharati
>> 
>> Sent from my iPad
>> 
>> Fortigate Filtered
> 

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