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https://issues.apache.org/jira/browse/MAHOUT-862?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13142275#comment-13142275
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Ted Dunning commented on MAHOUT-862:
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{quote}
Are speed gains on bytebuffers a result of unsafe underlying buffer accesses?
{quote}
No. The speed gains are largely because getLong works really well on
ByteBuffers (certainly better than byte by byte shift and mask code). That
then allows the JVM to do better loop optimizations (I think).
> MurmurHash 3.0
> --------------
>
> Key: MAHOUT-862
> URL: https://issues.apache.org/jira/browse/MAHOUT-862
> Project: Mahout
> Issue Type: Improvement
> Reporter: Grant Ingersoll
> Assignee: Grant Ingersoll
> Priority: Minor
> Attachments: MAHOUT-862.patch
>
>
> Yonik has ported an implementation of MurmurHash 3.0 and put it in the public
> domain: http://www.lucidimagination.com/blog/2011/09/15/murmurhash3-for-java/
> It's a port of https://sites.google.com/site/murmurhash/ which says:
> {quote}
> (I reserve the right to tweak the constants after people have had a chance to
> bang on it). Murmur3 has better performance than MurmurHash2, no repetition
> flaw, comes in 32/64/128-bit versions for both x86 and x64 platforms, and the
> 128-bit x64 version is blazing fast - over 5 gigabytes per second on my 3
> gigahertz Core 2.
> In addition, the library of test code that I use to test MurmurHash (called
> SMHasher) has been released - it's still rough (and will only compile under
> VC++ at the moment), but it contains everything needed to verify hash
> functions of arbitrary output bit-lengths.
> Murmur3 and all future versions will be hosted on Google Code here -
> http://code.google.com/p/smhasher/ - you can access the codebase via the
> 'Source' tab at the top.
> {quote}
> See also http://code.google.com/p/smhasher/
> We should add support for it and hook into MinHash
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