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https://issues.apache.org/jira/browse/HBASE-16876?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15602315#comment-15602315
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Neal Young commented on HBASE-16876:
------------------------------------

I took a look at the docs, got stuck at step 4 (under the contributors section) 
of http://accumulo.apache.org/git.html -- not sure what the 'lowest fixVersion' 
is.  Also, didn't know where to find 'dev-support/submit-patch.py' referenced 
at http://hbase.apache.org/book.html#submitting.patches, etc.  I think this is 
above my pay grade.  (I've not checked out the repository or worked on the 
source at all before.)  Can someone more familiar with how to submit the patch 
do it?



> RatioBasedCompactionPolicy ignores mayBeStuck
> ---------------------------------------------
>
>                 Key: HBASE-16876
>                 URL: https://issues.apache.org/jira/browse/HBASE-16876
>             Project: HBase
>          Issue Type: Bug
>          Components: Compaction
>            Reporter: Neal Young
>              Labels: newbie
>
> I'm a newbie so may not be reporting this bug correctly.  The bug currently 
> shows in lines 181 - 190 here : 
> http://hbase.apache.org/xref/org/apache/hadoop/hbase/regionserver/compactions/RatioBasedCompactionPolicy.html#181
>  .
> {code:title=Bar.java|borderStyle=solid}
> 176     while (countOfFiles - start >= comConf.getMinFilesToCompact() &&
> 177       fileSizes[start] > Math.max(comConf.getMinCompactSize(),
> 178           (long) (sumSize[start + 1] * ratio))) {
> 179       ++start;
> 180     }
> 181     if (start < countOfFiles) {
> 182       LOG.info("Default compaction algorithm has selected " + 
> (countOfFiles - start)
> 183         + " files from " + countOfFiles + " candidates");
> 184     } else if (mayBeStuck) {
> 185       // We may be stuck. Compact the latest files if we can.
> 186       int filesToLeave = candidates.size() - 
> comConf.getMinFilesToCompact();
> 187       if (filesToLeave >= 0) {
> 188         start = filesToLeave;
> 189       }
> 190     }
> {code}
> On reaching line 176, start = 0.  When comConf.getMinFilesToCompact() is at 
> least 2 (as occurs in the default), the while loop is guaranteed to terminate 
> with start < countOfFiles.  Hence, the else clause starting at line 184 never 
> executes, regardless of the value of mayBeStuck.
> Perhaps the following code would be better, but I'm not sure:
> {code:title=Bar.java|borderStyle=solid}
>     while (start < countOfFiles
>            && fileSizes[start] > Math.max(comConf.getMinCompactSize(),
>                                           (long) (sumSize[start + 1] * 
> ratio))) {
>         ++start;
>     }
>     if (countOfFiles - start < comConf.getMinFilesToCompact()) {
>         if (mayBeStuck && countOfFiles >= comConf.getMinFilesToCompact()) {
>             start = countOfFiles - comConf.getMinFilesToCompact();
>         } else {
>             start = countOfFiles;
>         }
>     }
>     if (countOfFiles - start > 0) {
>         LOG.info("Default compaction algorithm has selected " + (countOfFiles 
> - start)
>                  + " files from " + countOfFiles + " candidates");
>     }
> {code}



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