hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Amareshwari Sriramadasu (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-5337) JobTracker greedily schedules tasks without running tasks to join
Date Wed, 25 Mar 2009 09:14:52 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-5337?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12689040#action_12689040
] 

Amareshwari Sriramadasu commented on HADOOP-5337:
-------------------------------------------------

Some comments:
1. You can move recoveryManager.unMarkTracker call to hasRestarted() check, instead of doing
it in processHeartbeat.
2. recoveredTrackers Set should be made concurrent set.

> JobTracker greedily schedules tasks without running tasks to join
> -----------------------------------------------------------------
>
>                 Key: HADOOP-5337
>                 URL: https://issues.apache.org/jira/browse/HADOOP-5337
>             Project: Hadoop Core
>          Issue Type: Bug
>          Components: mapred
>    Affects Versions: 0.20.0
>            Reporter: Karam Singh
>            Assignee: Amar Kamat
>         Attachments: HADOOP-5337-v1.7.patch
>
>
> This issue was observed when JobTracker was restarted 3 times and observed that 4 instances
of each reduce task were running. This issue is observed when cluster is not fully occupied.
> In testcase: Map/reduces capacity is 200/200 slots respectively and Job profile is 11000
maps, 10 reduces and speculative execution is off.  JobTracker was restarted 3 times in small
intervals of about 5 mins and after recovery, 40 reduce tasks were running. Task details web
page (taskdetails.jsp) was  showing 4 running attempts of each reduce task.

-- 
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