You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-dev@hadoop.apache.org by "Sreekanth Ramakrishnan (JIRA)" <ji...@apache.org> on 2009/05/13 14:40:45 UTC

[jira] Updated: (HADOOP-4981) Prior code fix in Capacity Scheduler prevents speculative execution in jobs

     [ https://issues.apache.org/jira/browse/HADOOP-4981?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Sreekanth Ramakrishnan updated HADOOP-4981:
-------------------------------------------

    Attachment: HADOOP-4981-1.patch

Attaching patch incorporating the approach mentioned in [Hemanth's Comment| https://issues.apache.org/jira/browse/HADOOP-4981?focusedCommentId=12663260&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#action_12663260]

Added two new test cases:
* Case to check normal jobs with speculative maps and reduces.
* Case to check High ram job having speculative maps when pending tasks are zero

> Prior code fix in Capacity Scheduler prevents speculative execution in jobs
> ---------------------------------------------------------------------------
>
>                 Key: HADOOP-4981
>                 URL: https://issues.apache.org/jira/browse/HADOOP-4981
>             Project: Hadoop Core
>          Issue Type: Bug
>          Components: contrib/capacity-sched
>            Reporter: Vivek Ratan
>         Attachments: 4981.1.patch, 4981.2.patch, HADOOP-4981-1.patch
>
>
> As part of the code fix for HADOOP-4035, the Capacity Scheduler obtains a task from JobInProgress (calling obtainNewMapTask() or obtainNewReduceTask()) only if the number of pending tasks for a job is greater than zero (see the if-block in TaskSchedulingMgr.getTaskFromJob()). So, if a job has no pending tasks and only has running tasks, it will never be given a slot, and will never have a chance to run a speculative task. 

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