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https://issues.apache.org/jira/browse/HBASE-18133?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16378694#comment-16378694
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Josh Elser commented on HBASE-18133:
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RB is happy now, linked above.
> Low-latency space quota size reports
> ------------------------------------
>
> Key: HBASE-18133
> URL: https://issues.apache.org/jira/browse/HBASE-18133
> Project: HBase
> Issue Type: Improvement
> Reporter: Josh Elser
> Assignee: Josh Elser
> Priority: Major
> Fix For: 3.0.0
>
> Attachments: HBASE-18133.001.patch, HBASE-18133.002.patch,
> HBASE-18133.003.patch, HBASE-18133.004.patch, HBASE-18133.005.patch
>
>
> Presently space quota enforcement relies on RegionServers sending reports to
> the master about each Region that they host. This is done by periodically,
> reading the cached size of each HFile in each Region (which was ultimately
> computed from HDFS).
> This means that the Master is unaware of Region size growth until the the
> next time this chore in a RegionServer fires which is a fair amount of
> latency (a few minutes, by default). Operations like flushes, compactions,
> and bulk-loads are delayed even though the RegionServer is running those
> operations locally.
> Instead, we can create an API which these operations could invoke that would
> automatically update the size of the Region being operated on. For example, a
> successful flush can report that the size of a Region increased by the size
> of the flush. A compaction can subtract the size of the input files of the
> compaction and add in the size of the resulting file.
> This de-couples the computation of a Region's size from sending the Region
> sizes to the Master, allowing us to send reports more frequently, increasing
> the responsiveness of the cluster to size changes.
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