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Posted to mapreduce-user@hadoop.apache.org by Pedro Costa <ps...@gmail.com> on 2011/03/24 19:37:06 UTC

phases in tasks

Hi,

1 - A Task is composed by several phases:
STARTING, MAP/REDUCE, SHUFFLE, SORT, CLEANUP.

A JobTracker and a TaskTracker also has phases?

2 - It exists also the following phases
RUNNING,
		SUCCEEDED,
		FAILED,
		UNASSIGNED,
		KILLED,
		COMMIT_PENDING,
		FAILED_UNCLEAN,
		KILLED_UNCLEAN,

These phases also belong to the Map or Reduce tasks. So, it exists two
group of phases. Why is that?

Thanks,

-- 
Pedro

Re: phases in tasks

Posted by Pedro Costa <ps...@gmail.com>.
1 - So what's the reason to exist 2 group of phases?

2 - A JobTracker and a TaskTracker also has phases?


On Thu, Mar 24, 2011 at 6:42 PM, Arun C Murthy <ac...@yahoo-inc.com> wrote:
>
> On Mar 24, 2011, at 11:37 AM, Pedro Costa wrote:
>
>> Hi,
>>
>> 1 - A Task is composed by several phases:
>> STARTING, MAP/REDUCE, SHUFFLE, SORT, CLEANUP.
>>
>
> Right. These are 'phases' for a map and/or reduce task after it starts
> running.
>
>> A JobTracker and a TaskTracker also has phases?
>>
>> 2 - It exists also the following phases
>> RUNNING,
>>                SUCCEEDED,
>>                FAILED,
>>                UNASSIGNED,
>>                KILLED,
>>                COMMIT_PENDING,
>>                FAILED_UNCLEAN,
>>                KILLED_UNCLEAN,
>>
>> These phases also belong to the Map or Reduce tasks. So, it exists two
>> group of phases. Why is that?
>>
>
> These are 'states' for either map or reduce tasks, starting from their
> creation.
>
> Hope that helps.
>
> Arun
>



-- 
Pedro

Re: phases in tasks

Posted by Arun C Murthy <ac...@yahoo-inc.com>.
On Mar 24, 2011, at 11:37 AM, Pedro Costa wrote:

> Hi,
>
> 1 - A Task is composed by several phases:
> STARTING, MAP/REDUCE, SHUFFLE, SORT, CLEANUP.
>

Right. These are 'phases' for a map and/or reduce task after it starts  
running.

> A JobTracker and a TaskTracker also has phases?
>
> 2 - It exists also the following phases
> RUNNING,
> 		SUCCEEDED,
> 		FAILED,
> 		UNASSIGNED,
> 		KILLED,
> 		COMMIT_PENDING,
> 		FAILED_UNCLEAN,
> 		KILLED_UNCLEAN,
>
> These phases also belong to the Map or Reduce tasks. So, it exists two
> group of phases. Why is that?
>

These are 'states' for either map or reduce tasks, starting from their  
creation.

Hope that helps.

Arun