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https://issues.apache.org/jira/browse/HADOOP-2654?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12560881#action_12560881
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Hadoop QA commented on HADOOP-2654:
-----------------------------------

+1 overall.  Here are the results of testing the latest attachment 
http://issues.apache.org/jira/secure/attachment/12373593/counting-overflow-fourbit.patch
against trunk revision r613499.

    @author +1.  The patch does not contain any @author tags.

    javadoc +1.  The javadoc tool did not generate any warning messages.

    javac +1.  The applied patch does not generate any new compiler warnings.

    findbugs +1.  The patch does not introduce any new Findbugs warnings.

    core tests +1.  The patch passed core unit tests.

    contrib tests +1.  The patch passed contrib unit tests.

Test results: 
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1664/testReport/
Findbugs warnings: 
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1664/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html
Checkstyle results: 
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1664/artifact/trunk/build/test/checkstyle-errors.html
Console output: 
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1664/console

This message is automatically generated.

> CountingBloomFilter can overflow its storage
> --------------------------------------------
>
>                 Key: HADOOP-2654
>                 URL: https://issues.apache.org/jira/browse/HADOOP-2654
>             Project: Hadoop
>          Issue Type: Bug
>          Components: contrib/hbase
>            Reporter: Stu Hood
>         Attachments: counting-overflow-fourbit.patch, 
> counting-overflow-fourbit.patch, counting-overflow.patch
>
>
> The org.onelab.filter.CountingBloomFilter implementation does not check the 
> value of a bucket before incrementing/decrementing it. The buckets in a 
> Counting Bloom filter must not be allowed to overflow, and if they reach 
> their maximum value, they must not be allowed to decrement. This is the only 
> way to preserve the assumptions of the filter (without larger buckets). See: 
> http://en.wikipedia.org/wiki/Bloom_filter#Counting_filters
> Currently, if enough values hash to a bucket, the CountingBloomFilter may 
> begin reporting false negatives when it wraps back around to 0.

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