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Hive, mail # user - Modify the number of map tasks


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Re: Modify the number of map tasks
imen Megdiche 2012-12-12, 12:11
the size of data 49 MB and n of map 4
the web UI JobTrackerHost:50030 does not wok, what should i do to make this
appear , i work on ubuntu
2012/12/12 Mohammad Tariq <[EMAIL PROTECTED]>

> Hi Imen,
>
>      You can visit the MR web UI at "JobTrackerHost:50030" and see all the
> useful information like no. of mappers, no of reducers, time taken  for the
> execution etc.
>
> One quick question for you, what is the size of your data and what is the
> no of maps which you are getting right now?
>
> Regards,
>     Mohammad Tariq
>
>
>
> On Wed, Dec 12, 2012 at 5:11 PM, imen Megdiche <[EMAIL PROTECTED]>wrote:
>
>> Thank you Mohammad but the number of map tasks still the same in the
>> execution. Do you know how to capture the time spent on execution.
>>
>>
>> 2012/12/12 Mohammad Tariq <[EMAIL PROTECTED]>
>>
>>> 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
>>>>
>>>
>>>
>>
>