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From "ma qiang" <maqiang1...@gmail.com>
Subject Re: how many map in a map task?
Date Mon, 10 Nov 2008 08:49:52 GMT
Thanks very much.
However, I want to use the number of the map in my program. for
example.  There are 100 map in a map task, and I want to collect all
the values, and analyze these values then output the last result in
the last map.
generally, there is no ouput in the first 99 map, only output exists
in the last map.
So I should know how many map in a map task.



On Mon, Nov 10, 2008 at 4:33 PM, Billy Pearson
<sales@pearsonwholesale.com> wrote:
> If you are using TableMap to read the data back each mapper will map over
> all the rows in a single region.
>
> You can use counters to count the records so we can get a total records.
>
> but there is not set number of maps a mapper will process it depends on the
> input.
>
> Billy
>
>
>
> "ma qiang" <maqiang1984@gmail.com> wrote in message
> news:2af70f430811100011n5323ff03h3417aac50d5f0cc6@mail.gmail.com...
>>
>> hi all,
>>    I hava a data set stored in hbase, and I run a mapreduce program
>> to analyze. Now I want to know how many map in a map task?  Who can
>> tell me?
>>    Thanks a lot.
>>
>> yours qiang.
>>
>
>
>

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