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https://issues.apache.org/jira/browse/HBASE-69?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12568275#action_12568275
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Jim Kellerman commented on HBASE-69:
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> stack - 12/Feb/08 09:07 AM
> Why when only one store, blocking is disabled? (Whats to stop update rate
> from overwhelming flusher
> in one-store case?)
If we block based on the number of outstanding cache flush requests (which is
currently how it works for
more than one store), then we cannot take updates while that single store is
flushed, which didn't seem
like a good idea.
What I wanted to do was to put a policy in place for this patch that was "good
enough" until more
sophisticated policies (which balance the memory in the region server) were
done in HBASE-70,
which is going to address region server memory management.
> [hbase] Make cache flush triggering less simplistic
> ---------------------------------------------------
>
> Key: HBASE-69
> URL: https://issues.apache.org/jira/browse/HBASE-69
> Project: Hadoop HBase
> Issue Type: Improvement
> Components: regionserver
> Reporter: stack
> Assignee: Jim Kellerman
> Fix For: 0.2.0
>
> Attachments: patch.txt, patch.txt, patch.txt, patch.txt, patch.txt,
> patch.txt, patch.txt, patch.txt, patch.txt, patch.txt, patch.txt, patch.txt
>
>
> When flusher runs -- its triggered when the sum of all Stores in a Region > a
> configurable max size -- we flush all Stores though a Store memcache might
> have but a few bytes.
> I would think Stores should only dump their memcache disk if they have some
> substance.
> The problem becomes more acute, the more families you have in a Region.
> Possible behaviors would be to dump the biggest Store only, or only those
> Stores > 50% of max memcache size. Behavior would vary dependent on the
> prompt that provoked the flush. Would also log why the flush is running:
> optional or > max size.
> This issue comes out of HADOOP-2621.
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