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https://issues.apache.org/jira/browse/MAHOUT-862?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13142258#comment-13142258
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Dawid Weiss commented on MAHOUT-862:
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Are speed gains on bytebuffers a result of unsafe underlying buffer accesses? A
simple array loop with predictable ends should be optimized pretty much the
same way though (boundary checks only, followed by no-checks accesses); wonder
where the gain comes from then?
Also, this could be rewritten to actually make use of Unsafe if it's available
-- I bet with larger memory chunks the speed gain would be noticeable.
> 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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