[ 
https://issues.apache.org/jira/browse/MAPREDUCE-4495?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13477651#comment-13477651
 ] 

eric baldeschwieler commented on MAPREDUCE-4495:
------------------------------------------------

Directionally the Pig folks are very interested in replanning mid-job, so 
submitting a DAG to a static execution engine is kind of a step away from their 
medium term vision. Does not seem very helpful.

For Pig / Hive collaboration I think we should be focusing on lower level 
issues, like sorting out the details of hierarchical scheduling and sorting out 
how we can really reduce the launch latency of simple jobs to near zero.  Every 
framework will benefit from that!
                
> Workflow Application Master in YARN
> -----------------------------------
>
>                 Key: MAPREDUCE-4495
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-4495
>             Project: Hadoop Map/Reduce
>          Issue Type: New Feature
>    Affects Versions: 2.0.0-alpha
>            Reporter: Bo Wang
>            Assignee: Bo Wang
>         Attachments: MAPREDUCE-4495-v1.1.patch, MAPREDUCE-4495-v1.patch, 
> MapReduceWorkflowAM.pdf, yapp_proposal.txt
>
>
> It is useful to have a workflow application master, which will be capable of 
> running a DAG of jobs. The workflow client submits a DAG request to the AM 
> and then the AM will manage the life cycle of this application in terms of 
> requesting the needed resources from the RM, and starting, monitoring and 
> retrying the application's individual tasks.
> Compared to running Oozie with the current MapReduce Application Master, 
> these are some of the advantages:
>  - Less number of consumed resources, since only one application master will 
> be spawned for the whole workflow.
>  - Reuse of resources, since the same resources can be used by multiple 
> consecutive jobs in the workflow (no need to request/wait for resources for 
> every individual job from the central RM).
>  - More optimization opportunities in terms of collective resource requests.
>  - Optimization opportunities in terms of rewriting and composing jobs in the 
> workflow (e.g. pushing down Mappers).
>  - This Application Master can be reused/extended by higher systems like Pig 
> and hive to provide an optimized way of running their workflows.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to