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https://issues.apache.org/jira/browse/HBASE-14651?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14964953#comment-14964953
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Anoop Sam John commented on HBASE-14651:
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But the cluster configs to be adjusted so as to avoid the premature memstore
flushes no? So the flushed files will have sizes of this memstore flush size.
If we reduce the def size of min compaction to be much smaller than this, will
that be good.. at least we want the immediate flushed files to be compacted..
And if user dont want that, he can always reduce the config value. Do we
really need to reduce this default value?
> Default minimum compaction size is too high
> -------------------------------------------
>
> Key: HBASE-14651
> URL: https://issues.apache.org/jira/browse/HBASE-14651
> Project: HBase
> Issue Type: New Feature
> Reporter: Vladimir Rodionov
> Assignee: Vladimir Rodionov
> Attachments: HBASE-14651-v1.patch
>
>
> *hbase.hstore.compaction.min.size* defines minimum selection size which is
> always eligible for minor compaction (no compaction ratio check is performed
> on such file selections). Default size is equals to memstore flush size
> (128MB). First of all, even this value is too high for some (many)
> deployments, especially for write intensive, because of a small sizes of a
> memstore flushes, and if user increases memstore flush size (they usually set
> it to at least 256MB), they have no idea how will it impact the overall
> compaction process efficiency. With 256MB of minimum size to compact,
> compactor most of the time skips necessary file ratio checks and this will
> result in increased read/write IO during compactions, because of the
> unbalanced selections where relatively large files can be mixed with a newly
> created small store files. I think we should set this default minimum to
> 64MB and not to link it to memstore flush size at all.
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