Client interoperability, server selection.

Josh Snyder josh at
Tue Mar 11 18:47:12 UTC 2008

> Problems with Ketama implementation in libketama as of 0.1.1 are (I
> know there's a newer release, so maybe some are solved already?):

One more to add -- the consistent hashing is not quite perfect, in
that adding/removing a server causes some unrelated items to get
rehashed to different servers. There's a (too) long email about this,
including tests and an explanation of why it happens, at:

See also Richard Jones' recent comments at

It is not a critical problem (in an out-of-the-box test, only between
5% and 10% of items get rehashed unnecessarily), but if we're shooting
for a standard, it might be worth trying to resolve.


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