Better server selection client code?
alexs at advfn.com
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
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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