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From maha <m...@umail.ucsb.edu>
Subject Re: ToolRunner run function
Date Wed, 02 Mar 2011 21:04:58 GMT
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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