hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Robert Chansler (JIRA)" <j...@apache.org>
Subject [jira] Updated: (HADOOP-3383) Redundant computation in hashCode() implemenation
Date Fri, 08 Aug 2008 18:13:44 GMT

     [ https://issues.apache.org/jira/browse/HADOOP-3383?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Robert Chansler updated HADOOP-3383:
------------------------------------

    Component/s: dfs

> Redundant computation in hashCode() implemenation
> -------------------------------------------------
>
>                 Key: HADOOP-3383
>                 URL: https://issues.apache.org/jira/browse/HADOOP-3383
>             Project: Hadoop Core
>          Issue Type: Improvement
>          Components: dfs
>            Reporter: Tsz Wo (Nicholas), SZE
>
> 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