[jira] [Commented] (TEZ-3892) Tez-AM Daemon-Mode

["Eric Wohlstadter (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/TEZ-3892?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16345820#comment-16345820 ] 

Eric Wohlstadter commented on TEZ-3892:
---------------------------------------

[~sershe]

[~prasanth_j]

FYI

 

> Tez-AM Daemon-Mode
> ------------------
>
>                 Key: TEZ-3892
>                 URL: https://issues.apache.org/jira/browse/TEZ-3892
>             Project: Apache Tez
>          Issue Type: New Feature
>            Reporter: Eric Wohlstadter
>            Priority: Major
>
> This is a proposed opt-in feature.
> Tez AM already supports long-lived sessions, if desired a AM session can live indefinitely.
> However, new clients cannot connect to a long-lived AM session through the standard TezClient API. 
> TezClient API only provides a "start" method to initiate a connection, which always allocates a new AM from YARN.
>  # For interactive BI use-cases, this startup time can be significant.
>  # Hive is implementing a HiveServer2 High Availability feature.
>  ** When the singleton HS2 master server fails, the HS2 client is quickly redirected to a pre-warmed HS2 backup. 
>  # For the failover to complete quickly end-to-end, a Tez AM must also be pre-warmed and ready to accept connections.
> For more information, see design for: https://issues.apache.org/jira/browse/HIVE-18281.
> ----
> Anticipated changes:
>  # A {{reconnect(ApplicationId)}} method is added to TezClient. The functionality is similar to {{start}}
>  ** Code related to launching a new AM from the RM is factored out.
>  ** Since {{start}} and {{reconnect}} will share some code, this code is refactored into reusable helper methods.
>  ** A usage example is added to {{org/apache/tez/examples}}
>  # It is not a goal of this JIRA to ensure that running Tez DAGs can be recovered by a client using the {{reconnect}} API. The goal is only for maintaining a pool of warm Tez AMs to skip RM/container/JVM startup.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)