[ 
https://issues.apache.org/jira/browse/HIVE-10302?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Xuefu Zhang updated HIVE-10302:
-------------------------------
    Fix Version/s:     (was: spark-branch)
                   1.3.0

> Load small tables (for map join) in executor memory only once [Spark Branch]
> ----------------------------------------------------------------------------
>
>                 Key: HIVE-10302
>                 URL: https://issues.apache.org/jira/browse/HIVE-10302
>             Project: Hive
>          Issue Type: Improvement
>            Reporter: Jimmy Xiang
>            Assignee: Jimmy Xiang
>             Fix For: 1.3.0
>
>         Attachments: 10302.patch, HIVE-10302.2-spark.patch, 
> HIVE-10302.3-spark.patch, HIVE-10302.4-spark.patch, HIVE-10302.spark-1.patch
>
>
> Usually there are multiple cores in a Spark executor, and thus it's possible 
> that multiple map-join tasks can be running in the same executor 
> (concurrently or sequentially). Currently, each task will load its own copy 
> of the small tables for map join into memory, ending up with inefficiency. 
> Ideally, we only load the small tables once and share them among the tasks 
> running in that executor.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to