Better server selection client code?

Alex Stapleton alexs at
Fri Oct 20 14:49:36 UTC 2006

On 20 Oct 2006, at 15:26, Andrew Harbick wrote:

>> This exactly was my concern - load is not balanced with this
>> consistent hashing, unless I decide to keep multiple copies of each
>> entry - which ads a new dimension to choice of positions for a new
>> server to be added!
> My solution does balance load (assuming your key hash is evenly  
> distributed).  Servers are placed around the unit circle at even  
> intervals.

They are placed at intervals based on their hash value which isn't  
strictly an even distribution, especially with a small number of  
entries in the circle ;)

Of course as anyone who has read that paper already knows the easiest  
way to combat this is enter each server into the circle at multiple  
positions. I expect you can just enter some N copies evenly  
distributed around the circle and will quickly start to get a fairly  
even distribution. Precisely what you chose for N is something to  
experiment with though.

Oh, and how on earth do you handle collisions on the server hashes?  
We only have 4billion positions to play with here...

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