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From aaron morton <aa...@thelastpickle.com>
Subject Re: Decorator Algorithm
Date Thu, 23 Jun 2011 19:27:30 GMT
Various places in the code call IPartitioner.decorateKey() which returns a DecoratedKey<T>
which contains both the original key and the Token<T>

The RandomPartitioner md5 to hash the key ByteBuffer and create a BigInteger. OPP converts
the key into utf8 encoded String.  

Using the token to find which endpoints contain replicas is done by the AbstractReplicationStrategy.calculateNaturalEndpoints()
implementations. 

Does that help? 

-----------------
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
http://www.thelastpickle.com

On 23 Jun 2011, at 19:58, Jonathan Colby wrote:

> Hi -
> 
> I'd like to understand more how the token is hashed with the key to determine on which
node the data is stored - called decorating in cassandra speak.
> 
> Can anyone share any documentation on this or describe this more in detail?   Yes, I
could look at the code, but I was hoping to be able to read more about how it works first.
> 
> thanks.


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