Consistent hashing is a bit cleaner way to do it, but pretty much the same result as modulo-ing the user id against number of servers. At least as I understand it, you consistently hash something (a user id, a request URL, etc) into N buckets, where N is the number of servers, so changing N re-shuffles all of the buckets anyway.
Short of something like cassandra's ring topology, how would you use consistent hashing add new servers and assign them requests?
Short of something like cassandra's ring topology, how would you use consistent hashing add new servers and assign them requests?