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From Anseh Danesh <anseh.dan...@gmail.com>
Subject Re: number of map and reduce task does not change in M/R program
Date Sun, 20 Oct 2013 05:39:59 GMT
I try it in a small set of data, in about 600000 data and it does not take
too long. the execution time was reasonable. but in the set of 100000000
data it really works too bad. any thing else, I have 2 processors in my
machine, I think this amount of data is very huge for my processor and this
way it takes too long to process... what do you think about this?


On Sun, Oct 20, 2013 at 1:49 AM, Amr Shahin <amrnablus@gmail.com> wrote:

> Try running the job locally on a small set of the data and see if it takes
> too long. If so, you map code might have some performance issues
>
>
> On Sat, Oct 19, 2013 at 9:08 AM, Anseh Danesh <anseh.danesh@gmail.com>wrote:
>
>> Hi all.. I have a question.. I have a mapreduce program that get input
>> from cassandra. my input is a little big, about 100000000 data. my problem
>> is that my program takes too long to process, but I think mapreduce is good
>> and fast for large volume of data. so I think maybe I have problems in
>> number of map and reduce tasks.. I set the number of map and reduce asks
>> with JobConf, with Job, and also in conf/mapred-site.xml, but I don't see
>> any changes.. in my logs at first there is map 0% reduce 0% and after about
>> 2 hours working it shows map 1% reduce 0%..!! what should I do? please Help
>> me I really get confused...
>>
>
>

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