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https://issues.apache.org/jira/browse/DRILL-1525?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14171677#comment-14171677
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Parth Chandra commented on DRILL-1525:
--------------------------------------
Not sure how the hash32(long val, int seed) and hash32(int val, int seed) were
derived. If we take the hash64 function and pass in a long/int sized buffer to
the function, we will get, almost the same code as in these functions, but some
initialization of the h64 variable is missing -
h64 = seed + PRIME64_5;
h64 += len;
Also, xxhash.c has an implementation to compute a 32 bit hash. I would think
that it might be better to use that (though maybe a tad bit slower) instead of
computing the 64 bit hash and truncating it.
> Use XXHash algorithm for hash functions
> ---------------------------------------
>
> Key: DRILL-1525
> URL: https://issues.apache.org/jira/browse/DRILL-1525
> Project: Apache Drill
> Issue Type: Bug
> Reporter: Mehant Baid
> Assignee: Mehant Baid
> Fix For: 0.7.0
>
> Attachments: DRILL-1525.patch
>
>
> Currently we are using murmur hash algorithm for performing hash operations.
> We would like to move to XXHash which is a fast non-cryptographic hash
> algorithm. More information can be found here:
> https://code.google.com/p/xxhash/
> The implementation should also eliminates an extra copy of the ByteBuf to be
> consumed by the hash function.
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