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Date: Wed, 6 Nov 2013 08:29:17 +0530
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Subject: Re: which is better : form reducer or Driver
From: unmesha sreeveni <unmeshabiju@gmail.com>
To: User Hadoop <user@hadoop.apache.org>
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i am dealing with multiple mappers and 1 reducer. so which is best?


On Tue, Nov 5, 2013 at 6:28 PM, Chris Mawata <chris.mawata@gmail.com> wrote:

>  If you have multiple reducers you are doing it in parallel while in the
> driver it is surely single threaded so my bet would be on the reducers.
>
> Chris
>
>
> On 11/5/2013 6:15 AM, unmesha sreeveni wrote:
>
>  I am emiting 'A' value and 'B' value from reducer.
>
>  I need to do further calculations also.
> which is a better way?
>  1. Do all remamining computations within reducer , after emiting
> or
> 2.Do remaining computation In driver: read A and B value from part file
> and do further computations.
>
>  Pls suggest a better way.
>
>  --
> *Thanks & Regards*
>
>  Unmesha Sreeveni U.B
>
> *Junior Developer *
>
> *Amrita Center For Cyber Security *
>
>
> * Amritapuri. www.amrita.edu/cyber/ <http://www.amrita.edu/cyber/> *
>
>
>


-- 
*Thanks & Regards*

Unmesha Sreeveni U.B

*Junior Developer*

*Amrita Center For Cyber Security*


* Amritapuri.www.amrita.edu/cyber/ <http://www.amrita.edu/cyber/>*

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<div dir=3D"ltr"><div class=3D"gmail_default" style=3D"font-family:verdana,=
sans-serif">i am dealing with multiple mappers and 1 reducer. so which is b=
est?</div></div><div class=3D"gmail_extra"><br><br><div class=3D"gmail_quot=
e">On Tue, Nov 5, 2013 at 6:28 PM, Chris Mawata <span dir=3D"ltr">&lt;<a hr=
ef=3D"mailto:chris.mawata@gmail.com" target=3D"_blank">chris.mawata@gmail.c=
om</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">
 =20
   =20
 =20
  <div bgcolor=3D"#FFFFFF" text=3D"#000000">
    <div>If you have multiple reducers you are
      doing it in parallel while in the driver it is surely single
      threaded so my bet would be on the reducers.<span class=3D"HOEnZb"><f=
ont color=3D"#888888"><br>
      <br>
      Chris</font></span><div><div class=3D"h5"><br>
      <br>
      On 11/5/2013 6:15 AM, unmesha sreeveni wrote:<br>
    </div></div></div><div><div class=3D"h5">
    <blockquote type=3D"cite">
      <div dir=3D"ltr">
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f">I am emiting &#39;A&#39; value
          and &#39;B&#39; value from reducer.</div>
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f"><br>
        </div>
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f">I need to do further
          calculations also.</div>
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f">which is a better way?<br>
        </div>
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f">
          1. Do all remamining computations within reducer , after
          emiting=A0</div>
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f">or</div>
        <div class=3D"gmail_default" style=3D"font-family:verdana,sans-seri=
f">2.Do remaining
          computation In driver: read A and B value from part file and
          do further computations.</div>
        <div><br>
        </div>
        <div>
          <div class=3D"gmail_default" style=3D"font-family:verdana,sans-se=
rif">Pls suggest a better
            way.</div>
          <br>
        </div>
        -- <br>
        <div dir=3D"ltr"><i style=3D"color:rgb(102,0,0)">Thanks &amp;
            Regards</i>
          <div style=3D"color:rgb(102,0,0)"><i><br>
            </i></div>
          <div style=3D"color:rgb(102,0,0)">Unmesha Sreeveni U.B<i><br>
            </i></div>
          <div style=3D"color:rgb(102,0,0)"><i>Junior Developer<br>
            </i></div>
          <div style=3D"color:rgb(102,0,0)"><i>Amrita Center For Cyber
              Security<br>
            </i></div>
          <i><span>
              <div><span style=3D"color:rgb(102,0,0)">
                  Amritapuri.</span><br>
                <br>
                <a href=3D"http://www.amrita.edu/cyber/" target=3D"_blank">=
www.amrita.edu/cyber/</a></div>
            </span></i></div>
      </div>
    </blockquote>
    <br>
  </div></div></div>

</blockquote></div><br><br clear=3D"all"><div><br></div>-- <br><div dir=3D"=
ltr"><i style=3D"color:rgb(102,0,0)">Thanks &amp; Regards</i>
<div style=3D"color:rgb(102,0,0)"><i><br></i></div><div style=3D"color:rgb(=
102,0,0)">Unmesha Sreeveni U.B<i><br></i></div><div style=3D"color:rgb(102,=
0,0)"><i>Junior Developer<br></i></div><div style=3D"color:rgb(102,0,0)"><i=
>Amrita Center For Cyber Security<br>
</i></div><i><span><div><span style=3D"color:rgb(102,0,0)">
Amritapuri.</span><br><br><a href=3D"http://www.amrita.edu/cyber/" target=
=3D"_blank">www.amrita.edu/cyber/</a></div></span></i></div>
</div>

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