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From Andrey Ilinykh <ailin...@gmail.com>
Subject Re: hadoop consistency level
Date Thu, 18 Oct 2012 20:52:03 GMT
On Thu, Oct 18, 2012 at 1:34 PM, Michael Kjellman
<mkjellman@barracuda.com> wrote:
> Not sure I understand your question (if there is one..)
>
> You are more than welcome to do CL ONE and assuming you have hadoop nodes
> in the right places on your ring things could work out very nicely. If you
> need to guarantee that you have all the data in your job then you'll need
> to use QUORUM.
>
> If you don't specify a CL in your job config it will default to ONE (at
> least that's what my read of the ConfigHelper source for 1.1.6 shows)
>
I have two questions.
1. I can benefit from data locality (and Hadoop) only with CL ONE. Is
it correct?
2. With CL QUORUM cassandra reads data from all replicas. In this case
Hadoop doesn't give me any  benefits. Application running outside the
cluster has the same performance. Is it correct?

Thank you,
  Andrey

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