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https://issues.apache.org/jira/browse/HIVE-26145?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17532750#comment-17532750
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Janos Kovacs commented on HIVE-26145:
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[~zabetak] I agree, that bumping interval up is a workaround (that's what we 
are also using now). The proposed change is just a more elegant way to control 
it. The logic is copied from the TASK_THREADS_ALWAYS components, although those 
mostly have .frequency property,
metastore.acidmetrics.check.interval is the only having .interval and using the 
same 'if equals to zero then disable' configuration. 
 
I see the following options going forward:
- keep as-is and recommend using the large interval value to 'turn-off' the task
- keep using metastore.event.db.listener.clean.interval and extend the 
description in MetastoreConf.java stating that zero value will turn it off
- introduce a new configuration property explicitly planned to control enabling 
the task, like metastore.event.db.listener.clean.enabled, but that would not be 
consistent with the other housekeeping tasks
- rename the property to .frequency to mitigate the misunderstanding - but that 
would not be backward compatible.

What should we go forward with?

> Disable notification cleaner if interval is zero
> ------------------------------------------------
>
>                 Key: HIVE-26145
>                 URL: https://issues.apache.org/jira/browse/HIVE-26145
>             Project: Hive
>          Issue Type: Sub-task
>          Components: Metastore
>            Reporter: Janos Kovacs
>            Assignee: Janos Kovacs
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 0.5h
>  Remaining Estimate: 0h
>
> Many of the housekeeping/background tasks can be turned off in case of having 
> multiple instances running parallel. 
> Some are controlled via the housekeeping node configuration, others are not 
> started if their frequency is set to zero.
> The DB-Notification cleaner unfortunately doesn't have this functionality 
> which makes all instances to race for the lock on the backend HMS database. 
> Goal is to add change to be able to turn cleaner off in case if there are 
> multiple instances running (be able to bound it to the housekeeping 
> instance).  



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