Timeline service v2 integration with Federation

---------- Forwarded message ----------
From: Joep Rottinghuis 
Date: Fri, Jul 8, 2016 at 1:22 PM
Subject: Re: Federation -Timeline Service meeting notes
To: Subramaniam Venkatraman Krishnan 
Cc: Sangjin Lee, Vrushali Channapattan , Carlo Curino


Thanks for the notes.

I think that for federation to work smoothly in environments that use HDFS some additional considerations are needed, and possibly some solution like what we're using at Twitter with our nFly approach.

bq. - need a different entity table/some table to store node level metrics for physical cluster stats
Once we get to node-level rollup, we probably have to store something in a dc, cluster, rack, node hierarchy. In that case a physical cluster makes sense, but we'd still need some way to tie physical and logical together in order to make automatic error detection etc that we're envisioning feasible within a federated setup.

Cheers,

Joep

On Fri, Jul 8, 2016 at 1:00 PM, Subramaniam Venkatraman Krishnan  wrote:

    Thanks Vrushali for crisply capturing the essential from our rambling discussion J.

     

    Sangjin, I just want to add one comment to yours – we want to retain the physical cluster name (possibly as a new entity type) so that we don’t lose information & we can cluster level rollups even if they are not efficient.

     

    Additionally, based on the walkthrough of Federation design:

    ·         There was general agreement with the proposed approach.

    ·         There is a possibility to implement the Application TimelineCollector as an interceptor in the AMRMProxyService.

    ·         Joep raised the concern that it would be better if the RMs obtain the epoch from FederationStateStore. This is not currently in the roadmap of our MVP but we definitely plan to address this in future.

     

    Regards,

    Subru

     

    From: Sangjin Lee
    Sent: Thursday, July 07, 2016 6:22 PM
    To: Vrushali Channapattan 
    Cc: Joep Rottinghuis; Carlo Curino; Subramaniam Venkatraman Krishnan 
    Subject: Re: Federation -Timeline Service meeting notes

     

    Thanks for the summary Vrushali!

     

    Just so that we're on the same page regarding the terminology, I understand we're using the terms "logical cluster" and "federated cluster" interchangeably.

     

    Also, between using the federated cluster name and the home cluster name as a solution, I think we were leaning towards the federated cluster name (although not concluded).

     

    On Thu, Jul 7, 2016 at 4:33 PM, Vrushali Channapattan wrote:

         

        For Federation:

        - all entities that belong to the same flow run should have the same cluster name

        - app id in the same flow run strongly ordered in time

        - need a logical cluster name and physical cluster name

        For Timeline Service:

        - need to store physical cluster id and logical cluster id so that we don't lose information at any level (flow/app/entity etc)

        - add a  new table app id to cluster mapping table

        - need a different entity table/some table to store node level metrics for physical cluster stats

        For the Cluster Naming convention:

        - three situations for cluster name:

        ----> app submitted to router should take federated cluster name

        ----> app submitted directly to RM should take physical cluster name

        ----> Info about the physical cluster  in entities?

        - suggestion to set the cluster name as yarn tag at the router level (in the app submission context)