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https://issues.apache.org/jira/browse/HADOOP-2365?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12549100
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Jim Kellerman commented on HADOOP-2365:
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-1 on patch. This section of code should read:
{code}
int[] result = new int[nbHash];
for (int i = 0, initval = 0; i < nbHash; i++) {
initval = result[i] = Math.abs(JenkinsHash.hash(b, initval)) % maxValue;
}
return result;
{code}
However, thanks for finding my stupid mistake.
> Result of HashFunction.hash() contains all identical values
> -----------------------------------------------------------
>
> Key: HADOOP-2365
> URL: https://issues.apache.org/jira/browse/HADOOP-2365
> Project: Hadoop
> Issue Type: Bug
> Components: contrib/hbase
> Affects Versions: 0.16.0
> Reporter: Andrzej Bialecki
> Fix For: 0.16.0
>
> Attachments: hash-v1.patch
>
>
> There is a small bug in HashFunction:112 - initvalue should be changed
> between the loop iterations in order to spread the hash values over the whole
> allowed range. Instead the current code uses a fixed initvalue = 0, which
> gives all identical hash values in the result array. As a result,
> BloomFilter-s have extremely high rate of false positives.
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