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https://issues.apache.org/jira/browse/KUDU-2929?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16977885#comment-16977885
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Andrew Wong commented on KUDU-2929:
-----------------------------------

Also [~ZhangYao] good point about registering the DMS size as anchored memory. 
That seems to be an important point about update-heavy workloads. I've filedĀ 
KUDU-3002 for it.

> Don't starve compactions under memory pressure
> ----------------------------------------------
>
>                 Key: KUDU-2929
>                 URL: https://issues.apache.org/jira/browse/KUDU-2929
>             Project: Kudu
>          Issue Type: Improvement
>          Components: perf, tablet
>            Reporter: Andrew Wong
>            Assignee: Andrew Wong
>            Priority: Major
>             Fix For: 1.12.0
>
>
> When a server is under memory pressure, the maintenance manager exclusively 
> will look for the maintenance op that frees up the most memory. Some 
> operations, like compactions, do not register any amount of "anchored memory" 
> and effectively don't qualify for consideration.
> This means that when a tablet server is under memory pressure, compactions 
> will never be scheduled, even though compacting may actually end up reducing 
> memory (e.g. combining many rowsets-worth of CFileReaders into a single 
> rowset). While it makes sense to prefer flushes to compactions, it probably 
> doesn't make sense to do nothing vs compact.



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