hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Hudson (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HDFS-288) Redundant computation in hashCode() implemenation
Date Thu, 10 Sep 2009 10:40:58 GMT

    [ https://issues.apache.org/jira/browse/HDFS-288?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12753560#action_12753560
] 

Hudson commented on HDFS-288:
-----------------------------

Integrated in Hdfs-Patch-h5.grid.sp2.yahoo.net #21 (See [http://hudson.zones.apache.org/hudson/job/Hdfs-Patch-h5.grid.sp2.yahoo.net/21/])
    

> Redundant computation in hashCode() implemenation
> -------------------------------------------------
>
>                 Key: HDFS-288
>                 URL: https://issues.apache.org/jira/browse/HDFS-288
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>            Reporter: Tsz Wo (Nicholas), SZE
>            Assignee: Tsz Wo (Nicholas), SZE
>             Fix For: 0.21.0
>
>         Attachments: h288_20090820.patch
>
>
> In some hashCode() implementation (e.g. Block.hashCode()), the formula has the form
> {noformat}
> 37 * 17 + f(x),
> {noformat}
> where f( x ) is some function.  Adding 37*17 to f( x ) shifts the value of f( x ).  It
is not effective to do shifting in hash functions.  The computation is redundant.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message