Hi again Jim and Ted,

 I understood that each mapper will be getting a block of lines... but even 
thought I had only 2 mappers for a 16 lines of input file and TextInputFormat 
is used. A map-function is processed for each of those 16 lines!

I wanted a block of lines per map ... hence something like map1 has 8 lines and 
map2 has 8 lines. 

So first question: is there a difference between Mappers and maps ?

Second: Does that mean I need to write my own inputFormat to make the 
InputSplit equal to multipleLines ???

Thank you,

Maha


On Feb 18, 2011, at 11:55 AM, Jim Falgout wrote:

> That's right. The TextInputFormat handles situations where records cross 
> split boundaries. What your mapper will see is "whole" records. 
> 
> -----Original Message-----
> From: maha [mailto:[email protected]] 
> Sent: Friday, February 18, 2011 1:14 PM
> To: common-user
> Subject: Quick question
> 
> Hi all,
> 
>  I want to check if the following statement is right:
> 
> If I use TextInputFormat to process a text file with 2000 lines (each ending 
> with \n) with 20 mappers. Then each map will have a sequence of COMPLETE 
> LINES . 
> 
> In other words,  the input is not split byte-wise but by lines. 
> 
> Is that right?
> 
> 
> Thank you,
> Maha
> 

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