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From aaron morton <aa...@thelastpickle.com>
Subject Re: How to find what node a key is on
Date Wed, 23 Mar 2011 23:31:00 GMT
Each row is stored on RF nodes, and your read will be sent to CL number of nodes. Messages
only take a single hop from the coordinator to each node the read is performed on, so the
networking overhead varies with the number of nodes involved in the request.  There are man
factors other than networking that influence the speed of a read request. 

There are features available to determine which nodes holds replicas for a particular key.
AFAIK they are not intended for use by clients. 

Are you currently having problems with read performance ? 

Hope that helps.
Aaron

 
On 24 Mar 2011, at 11:53, Sameer Farooqui wrote:

> Does anybody know if it's possible to find out what node a specific key/row lives on?
> 
> We have a 30 node cluster and I'm curious how much faster it'll be to read data directly
from the node that stores the data. 
> 
> We're using random partitioner, by the way.
> 
> 
> Sameer Farooqui
> Accenture Technology Labs
> 
> 


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