hadoop-common-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Gopal V (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HADOOP-9601) Support native CRC on byte arrays
Date Mon, 18 Aug 2014 22:01:19 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-9601?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14101388#comment-14101388
] 

Gopal V commented on HADOOP-9601:
---------------------------------

[~tlipcon]: Thanks, I never chased this issue down.

Been a year or so, but this patch fell off my TODO list because of a bad perf run with the
DataNode.

> Support native CRC on byte arrays
> ---------------------------------
>
>                 Key: HADOOP-9601
>                 URL: https://issues.apache.org/jira/browse/HADOOP-9601
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: performance, util
>    Affects Versions: 3.0.0
>            Reporter: Todd Lipcon
>            Assignee: Gopal V
>              Labels: perfomance
>         Attachments: HADOOP-9601-WIP-01.patch, HADOOP-9601-WIP-02.patch, HADOOP-9601-bench.patch,
HADOOP-9601-rebase+benchmark.patch, HADOOP-9601-trunk-rebase-2.patch, HADOOP-9601-trunk-rebase.patch
>
>
> When we first implemented the Native CRC code, we only did so for direct byte buffers,
because these correspond directly to native heap memory and thus make it easy to access via
JNI. We'd generally assumed that accessing byte[] arrays from JNI was not efficient enough,
but now that I know more about JNI I don't think that's true -- we just need to make sure
that the critical sections where we lock the buffers are short.



--
This message was sent by Atlassian JIRA
(v6.2#6252)

Mime
View raw message