On Sat, Jun 14, 2014 at 4:38 PM, John Meinel <j...@arbash-meinel.com> wrote:
> ... > > >> 2) If you have 2 services, you likely would rather them on the same AZ >>> rather than spread across different AZ because of the different cost of >>> network bandwidth. How do we manage multiple services? Do we just use a >>> strictly deterministic ordering? (always sort the AZ names, round robin >>> starting with the first one?) >>> >> >> It's non-deterministic. Pseudo-random choice of the least populous AZs >> for the distribution group. >> >> As for cost: this is why we have the placement directives. We default to >> spreading, but enable users to control placement if necessary. >> > > So default behavior matters. I feel that sharing AZ across services by > default would probably give a better user experience. (yes units of a given > service need to be spread for proper HA, but between them it probably > doesn't matter because if one is dead the group is dead.) > Round-robin on a sorted list of AZs sounds fine. I've created a backlog card to do that, though it may be simple enough to do it while I'm fixing the ec2 issue. > I'm curious how the behavior is different from existing use. If we have > always just had each service randomly distributed it probably doesn't > matter. > AFAIK, it's not defined anywhere. The AWS docs just say "if you don't specify, we'll choose one".
-- Juju-dev mailing list Juju-dev@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/juju-dev
