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From maha <m...@umail.ucsb.edu>
Subject Re: ToolRunner run function
Date Wed, 02 Mar 2011 21:11:34 GMT
On a pseudo distributed mode, it actually just "move" the copy and not reproduce it :)
Thanks anyways,

Maha
On Mar 2, 2011, at 1:04 PM, maha wrote:

> Thanks Mike :)
> 
> I was also wondering what if:
> 
>   hdfs.CopyToLocal( src-file, dst-file) ;   //  is executed on node N
> 
> and there exists a copy of src-file from the replication process in that same node(N)
local file system ?   
> 
> Will hdfs recognize that there is already a copy in there and hence just move that copy
to dst-file path ?
> OR
> Will hdfs go ahead with the copy and hence node N will have two copies of the src-file?
(ie. one on HDFS namespace and another in the local file system)
> 
> 
> Thanks,
> 
> Maha
> 
> On Mar 2, 2011, at 12:38 PM, Michael Segel wrote:
> 
>> 
>> 
>> Run is local to your edge machine where you launched your job.
>> It then connects to the cluster / job tracker ...
>> 
>> HTH
>> 
>> -Mike
>> 
>>> From: maha@umail.ucsb.edu
>>> Subject: ToolRunner run function
>>> Date: Wed, 2 Mar 2011 12:10:05 -0800
>>> To: common-user@hadoop.apache.org
>>> 
>>> Hi,
>>> 
>>> Assuming my program implements the ToolRunner, my question is where does the
"run" function execute?  ie. which daemon (DataNode/TT) ? or is it on the local machine where
it is run?
>>> 
>>> Thank you,
>>> Maha
>> 		 	   		  
> 


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