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Message-ID: <f21a45870808121515x4e85b3cv9432f03e5db17cbf@mail.gmail.com>
Date: Tue, 12 Aug 2008 15:15:12 -0700
From: "Ashish Venugopal" <arv@andrew.cmu.edu>
Sender: arv.andrew@gmail.com
To: core-user@hadoop.apache.org
Subject: Re: Difference between Hadoop Streaming and "Normal" mode
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There is definitely functionality in "normal" mode that is not available in
streaming, like the ability to write counters to instruments jobs. I
personally just use streaming, so I am interested to see if there are
further key differences...
Ashish

On Tue, Aug 12, 2008 at 3:09 PM, Gaurav Veda
<gveda+@cs.cmu.edu<gveda%2B@cs.cmu.edu>
> wrote:

> Hi All,
>
> This might seem too silly, but I couldn't find a satisfactory answer
> to this yet. What are the advantages / disadvantages of using Hadoop
> Streaming over the normal mode (wherein you write your own mapper and
> reducer in Java)? From what I gather, the real advantage of Hadoop
> Streaming is that you can use any executable (in c / perl / python
> etc) as a mapper / reducer.
> A slight disadvantage is that the default is to read (write) from the
> standard input (output) ... though one can specify their own Input and
> Output format (and package it with the default hadoop streaming jar
> file).
>
> My point is, why should I ever use the normal mode? Streaming seems
> just as good. Is there a performance problem or do I have only limited
> control over my job if I use the streaming mode or some other issue?
>
> Thanks!
> Gaurav
> --
> Share what you know, learn what you don't !
>

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