[
https://issues.apache.org/jira/browse/FLINK-3623?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15198510#comment-15198510
]
ASF GitHub Bot commented on FLINK-3623:
---------------------------------------
GitHub user greghogan opened a pull request:
https://github.com/apache/flink/pull/1806
[FLINK-3623] [runtime] Adjust MurmurHash Algorithm
Fix "hash *= n" to be "hash = hash * m + n".
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/greghogan/flink
3623_adjust_murmurhash_algorithm
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/flink/pull/1806.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #1806
----
commit 58dabef04d21c8e2794e5d255b6ff6f6077e273c
Author: Greg Hogan <[email protected]>
Date: 2016-03-16T18:18:03Z
[FLINK-3623] [runtime] Adjust MurmurHash Algorithm
Fix "hash *= n" to be "hash = hash * m + n".
----
> Adjust MurmurHash algorithm
> ---------------------------
>
> Key: FLINK-3623
> URL: https://issues.apache.org/jira/browse/FLINK-3623
> Project: Flink
> Issue Type: Improvement
> Components: Distributed Runtime
> Affects Versions: 1.1.0
> Reporter: Greg Hogan
> Assignee: Greg Hogan
> Priority: Trivial
>
> Flink's MurmurHash implementation differs from the published algorithm.
> From Flink's MathUtils.java:
> {code}
> code *= 0xe6546b64;
> {code}
> The Murmur3_32 algorithm as described by
> [Wikipedia|https://en.wikipedia.org/wiki/MurmurHash]:
> {code}
> m ← 5
> n ← 0xe6546b64
> hash ← hash × m + n
> {code}
> and in Guava's Murmur3_32HashFunction.java:
> {code}
> h1 = h1 * 5 + 0xe6546b64;
> {code}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
