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https://issues.apache.org/jira/browse/HADOOP-2588?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12558535#action_12558535
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Hadoop QA commented on HADOOP-2588:
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+1 overall. Here are the results of testing the latest attachment
http://issues.apache.org/jira/secure/attachment/12373071/patch.txt
against trunk revision r611727.
@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/1577/testReport/
Findbugs warnings:
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1577/artifact/trunk/build/test/findbugs/newPatchFindbugsWarnings.html
Checkstyle results:
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1577/artifact/trunk/build/test/checkstyle-errors.html
Console output:
http://lucene.zones.apache.org:8080/hudson/job/Hadoop-Patch/1577/console
This message is automatically generated.
> org.onelab.filter.BloomFilter class uses 8X the memory it should be using
> -------------------------------------------------------------------------
>
> Key: HADOOP-2588
> URL: https://issues.apache.org/jira/browse/HADOOP-2588
> Project: Hadoop
> Issue Type: Improvement
> Components: contrib/hbase
> Affects Versions: 0.16.0
> Environment: n/a
> Reporter: Ian Clarke
> Priority: Trivial
> Fix For: 0.16.0
>
> Attachments: patch.txt
>
>
> The org.onelab.filter.BloomFilter uses a boolean[] to store the filter,
> however in most Java implementations this will use a byte per bit stored,
> meaning that 8X the actual used memory is required. This is unfortunate as
> the whole point of a BloomFilter is to save memory.
> As a sidebar, the implementation looks a bit shaky in other ways, such as the
> way hashes are generated from a SHA1 digest in the Filter class, such as the
> way that it just assumes the digestBytes array will be long enough in the
> hash() method.
> I discovered this while looking for a good Bloom Filter implementation to use
> in my own project. In the end I went ahead and implemented my own, its very
> simple and pretty elegant (even if I do say so myself ;) - you are welcome to
> use it:
> http://locut.us/blog/2008/01/12/a-decent-stand-alone-java-bloom-filter-implementation/
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