hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Yuri Pradkin (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-1245) value for mapred.tasktracker.tasks.maximum taken from two different sources
Date Wed, 10 Oct 2007 00:06:50 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-1245?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12533553
] 

Yuri Pradkin commented on HADOOP-1245:
--------------------------------------

The patch is cool, I tested it on our hadoop cluster and it seems to be working. +1.

> value for mapred.tasktracker.tasks.maximum taken from two different sources
> ---------------------------------------------------------------------------
>
>                 Key: HADOOP-1245
>                 URL: https://issues.apache.org/jira/browse/HADOOP-1245
>             Project: Hadoop
>          Issue Type: Bug
>          Components: mapred
>    Affects Versions: 0.12.3
>            Reporter: Michael Bieniosek
>         Attachments: tasktracker-max-tasks-1245.patch
>
>
> I want to create a cluster with machines with different numbers of CPUs.  Consequently,
each machine should have a different value for mapred.tasktracker.tasks.maximum, since my
map tasks are CPU bound.
> However, hadoop uses BOTH the values for mapred.tasktracker.tasks.maximum on the jobtracker
and the tasktracker.  
> When a new job starts up, the jobtracker uses its (single) value for mapred.tasktracker.tasks.maximum
to assign tasks.  This means that each tasktracker gets the same number of tasks, regardless
of how I configured that particular machine.
> After the first task finishes on each tasktracker, the tasktracker will request new tasks
from the jobtracker according to the tasktracker's value for mapred.tasktracker.tasks.maximum.
 So after the first round of map tasks is done, the cluster reverts to a mode that works well
for heterogeneous clusters.
> The jobtracker should not consult its config for the value of mapred.tasktracker.tasks.maximum.
 It should assign tasks (or allow tasktrackers to request tasks) according to each tasktracker's
value of mapred.tasktracker.tasks.maximum.

-- 
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