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From Amr Shahin <amrnab...@gmail.com>
Subject Re: number of map and reduce task does not change in M/R program
Date Sat, 19 Oct 2013 22:19:55 GMT
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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