You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@spark.apache.org by "Cheng Hao (JIRA)" <ji...@apache.org> on 2014/11/12 16:20:33 UTC
[jira] [Updated] (SPARK-4367) Process the "distinct" value before
shuffling for aggregation
[ https://issues.apache.org/jira/browse/SPARK-4367?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Cheng Hao updated SPARK-4367:
-----------------------------
Issue Type: Sub-task (was: Improvement)
Parent: SPARK-4366
> Process the "distinct" value before shuffling for aggregation
> -------------------------------------------------------------
>
> Key: SPARK-4367
> URL: https://issues.apache.org/jira/browse/SPARK-4367
> Project: Spark
> Issue Type: Sub-task
> Components: SQL
> Reporter: Cheng Hao
>
> Most of aggregate function(e.g average) with "distinct" value will requires all of the records in the same group to be shuffled into a single node, however, as part of the optimization, those records can be partially aggregated before shuffling, that probably reduces the overhead of shuffling significantly.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org