Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
MapReduce, mail # user - mapred.tasktracker.map.tasks.maximum is not taking into effect


Copy link to this message
-
Re: mapred.tasktracker.map.tasks.maximum is not taking into effect
Devaraj Das 2011-07-06, 02:19
The properties mapred.tasktracker.{map,reduce}.tasks.maximum are node level
parameters, and are read by tasktrackers when they start up. Passing them in
the job confing doesn't do any change ...

On Tue, Jul 5, 2011 at 12:02 PM, Saket Joshi <[EMAIL PROTECTED]>wrote:

>  Praveen, ****
>
> ** **
>
> You also need to set the property “mapred.map.tasks”  to the value  derived
> from the following formula ( mapred.tasktracker.map.tasks.maximum * Number
> of tasktracker Nodes in your cluster) . I am using Hadoop 0.20.2 and I am
> able to increase the number of maps using these two mentoined properties.
> Similar settings apply  for  the reducer .****
>
> ** **
>
> -Saket****
>
> ** **
>
> *From:* [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
> *Sent:* Friday, July 01, 2011 1:03 PM
> *To:* [EMAIL PROTECTED]
> *Subject:* mapred.tasktracker.map.tasks.maximum is not taking into effect*
> ***
>
> ** **
>
> Hi all,****
>
> I am using hadoop 0.20.2. I am setting the property
> mapred.tasktracker.map.tasks.maximum = 4 (same for reduce also) on my job
> conf but I am still seeing max of only 2 map and reduce tasks on each node.
> I know my machine can run 4 maps and 4 reduce tasks in parallel. Is this a
> bug in 0.20.2 or am I doing something wrong?****
>
> ** **
>
> Configuration conf = new Configuration();****
>
>       conf.set("mapred.tasktracker.map.tasks.maximum", "4");****
>
>       conf.set("mapred.tasktracker.reduce.tasks.maximum", "4");****
>
> ** **
>
> Thanks****
>
> Praveen****
>
> This communication, along with any attachments, may include confidential
> TouchCommerce Inc. information. Any distribution or copying of this material
> is strictly prohibited. If you are not the intended recipient of this
> transmission, please contact the sender immediately.
>