You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@hive.apache.org by "Prasanth Jayachandran (JIRA)" <ji...@apache.org> on 2019/03/06 02:05:00 UTC
[jira] [Updated] (HIVE-20656) Sensible defaults: Map aggregation
memory configs are too aggressive
[ https://issues.apache.org/jira/browse/HIVE-20656?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Prasanth Jayachandran updated HIVE-20656:
-----------------------------------------
Attachment: HIVE-20656.2.patch
> Sensible defaults: Map aggregation memory configs are too aggressive
> --------------------------------------------------------------------
>
> Key: HIVE-20656
> URL: https://issues.apache.org/jira/browse/HIVE-20656
> Project: Hive
> Issue Type: Bug
> Affects Versions: 4.0.0, 3.2.0
> Reporter: Prasanth Jayachandran
> Assignee: Prasanth Jayachandran
> Priority: Major
> Attachments: HIVE-20656.1.patch, HIVE-20656.2.patch
>
>
> The defaults for the following configs seems to be too aggressive. In java this can easily lead to several full GC pauses whose memory cannot be reclaimed.
> {code:java}
> HIVEMAPAGGRHASHMEMORY("hive.map.aggr.hash.percentmemory", (float) 0.99,
> "Portion of total memory to be used by map-side group aggregation hash table"),
> HIVEMAPAGGRMEMORYTHRESHOLD("hive.map.aggr.hash.force.flush.memory.threshold", (float) 0.9,
> "The max memory to be used by map-side group aggregation hash table.\n" +
> "If the memory usage is higher than this number, force to flush data"),{code}
>
> We can be little bit conservative for these configs to avoid getting into GC pause.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)