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ketama.go
libketama-style consistent hashing in Go

Author: Nolan Caudill ([email protected])
Date: 2011-06-04
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This is a small library to do libketama-style consistent hashing. 

A common pattern in a caching cluster (eg, memcache) is to take the hash of the key modded by
the number of cache servers to determine which node to cache to. This provides a distribution as 
even as your hashing algorithm but whenever a server is added or removed, all your keys have to rehash.

With consistent hashing, in the event of the removal of a cache node, all keys that were hashing to one 
node to (in theory) evenly distribute to the other cache nodes. The addition of a cache node works in a 
similar manner in that all nodes will evenly give up a portion of their cache keys to the new node.

This is a first pass at this and things seems to work at first glance but consider this alpha.

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USAGE
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ketama_test.go provides a working example of how to use this library.