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Hive >> mail # user >> Modify the number of map tasks


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Re: Modify the number of map tasks
Hi Imen,

    You can add "mapred.map.tasks" property in your mapred-site.xml file.

But, it is just a hint for the InputFormat. Actually no. of maps is
actually determined by the no of InputSplits created by the InputFormat.

HTH

Regards,
    Mohammad Tariq

On Wed, Dec 12, 2012 at 4:11 PM, imen Megdiche <[EMAIL PROTECTED]>wrote:

> Hi,
>
> I try to force the number of map for the mapreduce job with the command :
>   public static void main(String[] args) throws Exception {
>
>           JobConf conf = new JobConf(WordCount.class);
>              conf.set("mapred.job.tracker", "local");
>          conf.set("fs.default.name", "local");
>           conf.setJobName("wordcount");
>
>           conf.setOutputKeyClass(Text.class);
>          conf.setOutputValueClass(IntWritable.class);
>
>            conf.setNumMapTask(6);
>           conf.setMapperClass(Map.class);
>           conf.setCombinerClass(Reduce.class);
>           conf.setReducerClass(Reduce.class);
> ...
> }
>
> But it doesn t work.
> What can i do to modify the number of map and reduce tasks.
>
> Thank you
>
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB