Hello, On Fri, Oct 18, 2013 at 06:54:40PM -0400, Bhaskar Maddala wrote: > Hello, > > We have been using haproxy for load balancing requests across our > backbends. We use consistent hashing, in experiments for the requests > processed and specific to our architecture we found dbj2 providing a better > distribution over sdbm when the remainder of the configuration was left > unchanged. > > We have a patched version of haproxy based on 1.4.24 that adds a config > option of hash-func with values sdbm and dbj2, sdbm as default, we have > been using dbj2 in production for a while now. I am writing to determine > interest if any for this change before submitting a patch.
I don't know these sdbm nor dbj2 functions. For the later I suspect you meant "djb2" instead which is the same as hash_djbx33 in tests_hashes.c. But sdbm I still don't know. In 1.5, an avalanche hash is always performed before applying the consistent hash, which should provide a smoother distribution than in 1.4. Could you please check if 1.5 still needs this ability to change the hash function ? I'm not opposed to a new parameter, but I'd prefer to avoid it if it's not necessary. Thanks, Willy
