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

Switch to Threaded View
Hive, mail # user - Modify the number of map tasks


Copy link to this message
-
Re: Modify the number of map tasks
imen Megdiche 2012-12-12, 12:44
My goal is to analyze the response time of MapReduce depending on the size
of the input files. I need to change the number of map and / or Reduce tasks
and recover the execution time. S it turns out that nothing works locally on my
pc :
neither hadoop job-status command job_local_0001 (which return no job found
)
nor localhost: 50030
I will be very grateful if you can help m better understand these problem
2012/12/12 Mohammad Tariq <[EMAIL PROTECTED]>

> Are you working locally?What exactly is the issue?
>
> Regards,
>     Mohammad Tariq
>
>
>
> On Wed, Dec 12, 2012 at 6:00 PM, imen Megdiche <[EMAIL PROTECTED]>wrote:
>
>> no
>>
>>
>> 2012/12/12 Mohammad Tariq <[EMAIL PROTECTED]>
>>
>>> Any luck with "localhost:50030"??
>>>
>>> Regards,
>>>     Mohammad Tariq
>>>
>>>
>>>
>>> On Wed, Dec 12, 2012 at 5:53 PM, imen Megdiche <[EMAIL PROTECTED]>wrote:
>>>
>>>> i run the job through the command line
>>>>
>>>>
>>>> 2012/12/12 Mohammad Tariq <[EMAIL PROTECTED]>
>>>>
>>>>> You have to replace "JobTrackerHost" in "JobTrackerHost:50030" with
>>>>> the actual name of the machine where JobTracker is running. For
>>>>> example, If you are working on a local cluster, you have to use
>>>>> "localhost:50030".
>>>>>
>>>>> Are you running your job through the command line or some IDE?
>>>>>
>>>>> Regards,
>>>>>     Mohammad Tariq
>>>>>
>>>>>
>>>>>
>>>>> On Wed, Dec 12, 2012 at 5:42 PM, imen Megdiche <
>>>>> [EMAIL PROTECTED]> wrote:
>>>>>
>>>>>> excuse me the data size is 98 MB
>>>>>>
>>>>>>
>>>>>> 2012/12/12 imen Megdiche <[EMAIL PROTECTED]>
>>>>>>
>>>>>>> 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);
>>>>>>>>>>> ...
>>>>