Mailing-List: contact mapreduce-issues-help@hadoop.apache.org; run by ezmlm
Precedence: bulk
Reply-To: mapreduce-issues@hadoop.apache.org
Date: Thu, 10 Jan 2013 13:26:20 +0000 (UTC)
From: "Hudson (JIRA)" <jira@apache.org>
To: mapreduce-issues@hadoop.apache.org
Message-ID: <JIRA.12625453.1356732273656.113253.1357824380447@arcas>
In-Reply-To: <JIRA.12625453.1356732273656@arcas>
References: <JIRA.12625453.1356732273656@arcas>
Subject: [jira] [Commented] (MAPREDUCE-4907) TrackerDistributedCacheManager
 issues too many getFileStatus calls
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/MAPREDUCE-4907?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13549622#comment-13549622 ] 

Hudson commented on MAPREDUCE-4907:
-----------------------------------

Integrated in Hadoop-Hdfs-trunk #1281 (See [https://builds.apache.org/job/Hadoop-Hdfs-trunk/1281/])
    MAPREDUCE-4907. TrackerDistributedCacheManager issues too many getFileStatus calls. (sandyr via tucu) (Revision 1431166)

     Result = FAILURE
tucu : http://svn.apache.org/viewcvs.cgi/?root=Apache-SVN&view=rev&rev=1431166
Files : 
* /hadoop/common/trunk/hadoop-mapreduce-project/CHANGES.txt
* /hadoop/common/trunk/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/JobSubmitter.java
* /hadoop/common/trunk/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/filecache/ClientDistributedCacheManager.java

                
> TrackerDistributedCacheManager issues too many getFileStatus calls
> ------------------------------------------------------------------
>
>                 Key: MAPREDUCE-4907
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-4907
>             Project: Hadoop Map/Reduce
>          Issue Type: Improvement
>          Components: mrv1, tasktracker
>    Affects Versions: 1.1.1
>            Reporter: Sandy Ryza
>            Assignee: Sandy Ryza
>             Fix For: 1.2.0, 2.0.3-alpha
>
>         Attachments: MAPREDUCE-4907.patch, MAPREDUCE-4907-trunk-1.patch, MAPREDUCE-4907-trunk-1.patch, MAPREDUCE-4907-trunk-1.patch, MAPREDUCE-4907-trunk.patch
>
>
> TrackerDistributedCacheManager issues a number of redundant getFileStatus calls when determining the timestamps and visibilities of files in the distributed cache.  300 distributed cache files deep in the directory structure can hammer HDFS with a couple thousand requests.
> A couple optimizations can reduce this load:
> 1. determineTimestamps and determineCacheVisibilities both call getFileStatus on every file.  We could cache the results of the former and use them for the latter.
> 2. determineCacheVisibilities needs to check that all ancestor directories of each file have execute permissions for everyone.  This currently entails a getFileStatus on each ancestor directory for each file.  The results of these getFileStatus calls could be cached as well.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira