> -----Original Message----- > From: Chris Friesen [mailto:chris.frie...@windriver.com] > Sent: 08 April 2014 15:19 > To: openstack-dev@lists.openstack.org > Subject: Re: [openstack-dev] [Nova] Hosts within two Availability Zones : > possible or not ? > > On 04/08/2014 07:25 AM, Jay Pipes wrote: > > On Tue, 2014-04-08 at 10:49 +0000, Day, Phil wrote: > >> On a large cloud you're protect against this to some extent if the > >> number of servers is >> number of instances in the quota. > >> > >> However it does feel that there are a couple of things missing to > >> really provide some better protection: > >> > >> - A quota value on the maximum size of a server group > >> - A policy setting so that the ability to use service-groups > >> can be controlled on a per project basis > > > > Alternately, we could just have the affinity filters serve as > > weighting filters instead of returning NoValidHosts. > > > > That way, a request containing an affinity hint would cause the > > scheduler to prefer placing the new VM near (or not-near) other > > instances in the server group, but if no hosts exist that meet that > > criteria, the filter simply finds a host with the most (or fewest, in > > case of anti-affinity) instances that meet the affinity criteria. > > I'd be in favor of this. I've actually been playing with an internal > patch to do both of these things, though in my case I was just doing it via > metadata on the group and a couple hacks in the scheduler and the compute > node. > > Basically I added a group_size metadata field and a "best_effort" flag to > indicate whether we should error out or continue on if the policy can't be > properly met. > I like the idea of the user being able to say if the affinity should be treated as a filter or weight.
In terms of group_size I'd want to able to impose a limit on that as an operator, not just have it in the control of the user (hence the quota idea) _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
