Hi
1- How does Hadoop decide where to save file blocks (I mean all files include files written by reducers)? Could you please give me a reference link?

This looks to be HDFS specific question. please send it to correct mailing list. cc'ed to mapreduce user if you have not registered for hdfs.

Please look at the previous discussion in mailing list about your question.
http://lucene.472066.n3.nabble.com/How-HDFS-decides-where-to-put-the-block-td2834463.html

Regards,
Uma
________________________________
From: Alieh Saeedi [[EMAIL PROTECTED]]
Sent: Saturday, February 04, 2012 1:16 PM
To: [EMAIL PROTECTED]
Subject: reducers output

Hi
1- How does Hadoop decide where to save file blocks (I mean all files include files written by reducers)? Could you please give me a reference link?

Alieh - you might want to look at MR concepts (job, input, output etc.).

The short answer is *hadoop* doesn't decide anything, it's upto the MR job to decide input/output etc.

You might want to read through this:
http://hadoop.apache.org/common/docs/stable/mapred_tutorial.html

Arun

On Feb 3, 2012, at 11:46 PM, Alieh Saeedi wrote:

> Hi
> 1- How does Hadoop decide where to save file blocks (I mean all files include files written by reducers)? Could you please give me a reference link?
>
>

--
Arun C. Murthy
Hortonworks Inc.
http://hortonworks.com/

Sorry. Ignore my previos answer. Was just thinking about normal HDFS files :-). In your question, they will be decided by your job itself. sorry for the confusion.
________________________________
From: Uma Maheswara Rao G [[EMAIL PROTECTED]]
Sent: Saturday, February 04, 2012 5:46 PM
To: [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Subject: RE: reducers output

This looks to be HDFS specific question. please send it to correct mailing list. cc'ed to mapreduce user if you have not registered for hdfs.

Please look at the previous discussion in mailing list about your question.
http://lucene.472066.n3.nabble.com/How-HDFS-decides-where-to-put-the-block-td2834463.html

Regards,
Uma
________________________________
From: Alieh Saeedi [[EMAIL PROTECTED]]
Sent: Saturday, February 04, 2012 1:16 PM
To: [EMAIL PROTECTED]
Subject: reducers output

Hi
1- How does Hadoop decide where to save file blocks (I mean all files include files written by reducers)? Could you please give me a reference link?