In Pseudo Mode where is the setting to increase the number of mappers or is this not possible.
Thanks
Sai

Hi
  I have done some tests in my  Pseudo Mode(CDH4.1.2)with MV2 yarn,and   :
  According to the doc:
  *mapreduce.jobtracker.address :*The host and port that the MapReduce job
tracker runs at. If "local", then jobs are run in-process as a single map
and reduce task.
  *mapreduce.job.maps (default value is 2)* :The default number of map
tasks per job. Ignored when mapreduce.jobtracker.address is "local".

  I changed the mapreduce.jobtracker.address = Hadoop:50031.

  And then run the wordcount examples:
  hadoop jar  hadoop-mapreduce-examples-2.0.0-cdh4.1.2.jar wordcount
input output

  the output logs are as follows:
        ....
   Job Counters
Launched map tasks=1
Launched reduce tasks=1
Data-local map tasks=1
Total time spent by all maps in occupied slots (ms)=60336
Total time spent by all reduces in occupied slots (ms)=63264
     Map-Reduce Framework
Map input records=5
Map output records=7
Map output bytes=56
Map output materialized bytes=76
        ....

 i seem to does not work.

 I thought maybe my input file is small-just 5 records . is it right?

regards

2013/3/14 Sai Sai <[EMAIL PROTECTED]>

>
>
> In Pseudo Mode where is the setting to increase the number of mappers or
> is this not possible.
> Thanks
> Sai
>

hi：
   i think i have got it . Thank you.

发自我的 iPhone

在 2013-3-15，18:32，Zheyi RONG <[EMAIL PROTECTED]> 写道：

> Indeed you cannot explicitly set the number of mappers, but still you can gain some control over it, by setting mapred.max.split.size, or mapred.min.split.size.
>
> For example, if you have a file of 10GB (10737418240 B), you would like 10 mappers, then each mapper has to deal with 1GB data.
> According to "splitsize = max(minimumSize, min(maximumSize, blockSize))", you can set mapred.min.split.size=1073741824 (1GB), i.e.    
> $hadoop jar -Dmapred.min.split.size=1073741824 yourjar yourargs
>
> It is well explained in thread: http://stackoverflow.com/questions/9678180/change-file-split-size-in-hadoop.
>
> Regards,
> Zheyi.
>
> On Fri, Mar 15, 2013 at 8:49 AM, YouPeng Yang <[EMAIL PROTECTED]> wrote:
>> s
>
>