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From Andrey Ilinykh <ailin...@gmail.com>
Subject Re: hadoop consistency level
Date Thu, 18 Oct 2012 20:29:28 GMT
On Thu, Oct 18, 2012 at 1:24 PM, Michael Kjellman
<mkjellman@barracuda.com> wrote:
> Well there is *some* data locality, it's just not guaranteed. My
> understanding (and someone correct me if I'm wrong) is that
> ColumnFamilyInputFormat implements InputSplit and the getLocations()
> method.
>
> http://hadoop.apache.org/docs/mapreduce/current/api/org/apache/hadoop/mapre
> duce/InputSplit.html
>
> ColumnFamilySplit.java contains logic to do it's best to determine what
> node that particular hadoop node contains the data for that mapper.
>
But no guarantee local data is in sync with other nodes. Which means
you have CL ONE. If you want CL QUORUM you have to make remote call,
no matter if data is local or not.

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