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https://issues.apache.org/jira/browse/HIVE-24406?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17316450#comment-17316450
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Sahana Bhat commented on HIVE-24406:
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The latest Hive version doesn't have the extra HiveConf object being created.
Instead a Configuration object gets initialised with the threadlocal conf
variable and so, this added latency seen in hive 2.3.4 is not an issue with the
latest version. Closing this ticket as a no-op.
> HiveConf creation in HiveMetastore's getMS() call adds ~100ms latency
> ---------------------------------------------------------------------
>
> Key: HIVE-24406
> URL: https://issues.apache.org/jira/browse/HIVE-24406
> Project: Hive
> Issue Type: Bug
> Components: Metastore
> Affects Versions: 2.3.4
> Reporter: Sahana Bhat
> Assignee: Sahana Bhat
> Priority: Major
> Attachments: Screenshot 2020-11-17 at 5.17.50 PM.png
>
>
> The changes to HMSHandler's getMSForConf introduced in the commit
> [https://github.com/apache/hive/commit/9a47cf9f92d1c8a4e72890e3dfe2d9567f12bfb5]
> makes getMSForConf and newRawStoreForConf static and hence adds an
> additional HiveConf object creation step for every metastore connection
> created.
> In a client like Presto, which creates a new metastore connection for every
> query, the object creation rate shoots up leading to higher heap usage, more
> frequent garbage collection, higher garbage collection times and increased
> latency in the service. We noticed a constant ~100ms increase in latency of
> all metastore calls during migration of HMS from 1x to 2x for Presto.
> PFA the latency difference of a get_table call between 1x and 2x. Min of 22ms
> in 1x vs 103ms in 2x
> !Screenshot 2020-11-17 at 5.17.50 PM.png|width=591,height=222!
>
>
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