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https://issues.apache.org/jira/browse/HBASE-14326?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14717504#comment-14717504
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Vladimir Rodionov commented on HBASE-14326:
-------------------------------------------

In ExploringCompactionPolicy, which is default, both: 
*hbase.hstore.compaction.max.size* and *hbase.hstore.compaction.min.size*  are 
applied to *selection* of files - not to a single file, as described 
erroneously in HBase book. 

> HBase book: fix definition of max min size to compact
> -----------------------------------------------------
>
>                 Key: HBASE-14326
>                 URL: https://issues.apache.org/jira/browse/HBASE-14326
>             Project: HBase
>          Issue Type: Bug
>          Components: documentation
>            Reporter: Vladimir Rodionov
>             Fix For: 2.0.0
>
>
> I think we need to change wording/definition of these config parameters in 
> HBase book, they are misleading:
> {quote}
> hbase.hstore.compaction.min.size
> Description
> A StoreFile smaller than this size will always be eligible for minor 
> compaction. HFiles this size or larger are evaluated by 
> hbase.hstore.compaction.ratio to determine if they are eligible. Because this 
> limit represents the "automatic include"limit for all StoreFiles smaller than 
> this value, this value may need to be reduced in write-heavy environments 
> where many StoreFiles in the 1-2 MB range are being flushed, because every 
> StoreFile will be targeted for compaction and the resulting StoreFiles may 
> still be under the minimum size and require further compaction. If this 
> parameter is lowered, the ratio check is triggered more quickly. This 
> addressed some issues seen in earlier versions of HBase but changing this 
> parameter is no longer necessary in most situations. Default: 128 MB 
> expressed in bytes.
> Default
> 134217728
> hbase.hstore.compaction.max.size
> Description
> A StoreFile larger than this size will be excluded from compaction. The 
> effect of raising hbase.hstore.compaction.max.size is fewer, larger 
> StoreFiles that do not get compacted often. If you feel that compaction is 
> happening too often without much benefit, you can try raising this value. 
> Default: the value of LONG.MAX_VALUE, expressed in bytes.
> {quote}
> For details, see HBASE-14263.



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