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https://issues.apache.org/jira/browse/HBASE-13884?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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stack resolved HBASE-13884.
---------------------------
Resolution: Fixed
Assignee: stack
Fix Version/s: 3.0.0
Pushed the attached .001 on this trivial issue.
> Fix Compactions section in HBase book
> -------------------------------------
>
> Key: HBASE-13884
> URL: https://issues.apache.org/jira/browse/HBASE-13884
> Project: HBase
> Issue Type: Bug
> Components: documentation
> Reporter: Vladimir Rodionov
> Assignee: stack
> Priority: Trivial
> Fix For: 3.0.0
>
> Attachments:
> 0001-HBASE-13884-Fix-Compactions-section-in-HBase-book.patch
>
>
> http://hbase.apache.org/book.html#_compaction
> {quote}
> Being Stuck
> When the MemStore gets too large, it needs to flush its contents to a
> StoreFile. However, a Store can only have hbase.hstore.blockingStoreFiles
> files, so the MemStore needs to wait for the number of StoreFiles to be
> reduced by one or more compactions. However, if the MemStore grows larger
> than hbase.hregion.memstore.flush.size, it is not able to flush its contents
> to a StoreFile. If the MemStore is too large and the number of StoreFiles is
> also too high, the algorithm is said to be "stuck". The compaction algorithm
> checks for this "stuck" situation and provides mechanisms to alleviate it.
> {quote}
> According to source code, this "stuck" situation has nothingg to do with
> MemStore size.
> {code}
> // Stuck and not compacting enough (estimate). It is not guaranteed that we
> will be
> // able to compact more if stuck and compacting, because ratio policy
> excludes some
> // non-compacting files from consideration during compaction (see
> getCurrentEligibleFiles).
> int futureFiles = filesCompacting.isEmpty() ? 0 : 1;
> boolean mayBeStuck = (candidateFiles.size() - filesCompacting.size() +
> futureFiles)
> >= storeConfigInfo.getBlockingFileCount();
> {code}
> If the number of store files which are not being compacted yet exceeds
> blocking file count +(potentially)1 - we say that compaction may be stuck.
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