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From Chris Mawata <chris.maw...@gmail.com>
Subject Re: hadoop -Mapreduce
Date Sat, 21 Dec 2013 19:51:16 GMT
Each mapper is already running in its own JVM. Maybe if you explain why you
want to start threads someone might have some suggestions.  (If at all
possible I suggest you avoid doing that)
Chris
On Dec 11, 2013 6:26 AM, "Ranjini Rathinam" <ranjinibecse@gmail.com> wrote:

> Hi,
>
> I am fresher to mapreduce concept,
> I would like to know how to implement multithread concept in mapreduce.
>
> Please provide sample program for implementating the above concept.
>
> Thanks in advance.
> Ranjini.R
>
> On Mon, Dec 9, 2013 at 12:34 PM, Ranjini Rathinam <ranjinibecse@gmail.com>wrote:
>
>> hi,
>>
>> Will these class support in hadoop 0.20 version. I am using this only.?
>>
>> Please suggest.
>>
>> Thanksin advance,
>>
>> Ranjini.R
>>
>>  On Mon, Dec 9, 2013 at 12:27 PM, Vinayakumar B <vinayakumar.b@huawei.com
>> > wrote:
>>
>>>  Hi Ranjini,
>>>
>>>
>>>
>>> Please check this mapper class whether this suites your needs.
>>>
>>> org.apache.hadoop.mapreduce.lib.map.MultithreadedMapper
>>>
>>>
>>>
>>> Thanks and Regards,
>>>
>>> Vinayakumar B
>>>
>>> *From:* Ranjini Rathinam [mailto:ranjinibecse@gmail.com]
>>> *Sent:* 09 December 2013 11:13
>>> *To:* user@hadoop.apache.org
>>> *Subject:* Re: hadoop -Mapreduce
>>>
>>>
>>>
>>> HI,
>>>
>>>
>>>
>>> I need to use thread functionality to run more than one mapper class
>>> parallelly.
>>>
>>>
>>>
>>> Please suggest with some sample code.
>>>
>>>
>>>
>>> Thanks in advance.
>>>
>>> On Fri, Dec 6, 2013 at 4:37 PM, Subroto <ssanyal@datameer.com> wrote:
>>>
>>> Hi Ranjini,
>>>
>>>
>>>
>>> The number of mappers depend on InputSplits and which intern depends on
>>> size of input data.
>>>
>>> The number of reducers can be configured by "mapred.reduce.tasks"
>>>
>>>
>>>
>>> Further you can get more information on numbers of Maps and Reduce for a
>>> Job from:
>>>
>>> http://wiki.apache.org/hadoop/HowManyMapsAndReduces
>>>
>>>
>>>
>>> Running parallel mappers and reducers depends on availability of map and
>>> reduce slots in the cluster.
>>>
>>>
>>>
>>> Cheers,
>>>
>>> Subroto Sanyal
>>>
>>>
>>>
>>> On Dec 6, 2013, at 12:00 PM, Ranjini Rathinam wrote:
>>>
>>>
>>>
>>>  HI,
>>>
>>>
>>>
>>> How to run more than one mapper and reduce parallelly.?
>>>
>>>
>>>
>>> Please suggest.Thanks in advance.
>>>
>>>
>>>
>>> Ranjini.
>>>
>>>
>>>
>>>
>>>
>>
>>
>

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