Re: [Users] How to force VM's to run on different hosts?

From: "Itamar Heim" <iheim(a)redhat.com&gt; To: "Maxim Burgerhout" <maxim(a)wzzrd.com&gt; Cc: users(a)ovirt.org, "Laszlo Hornyak" <lhornyak(a)redhat.com&gt;, "Doron Fediuck" <dfediuck(a)redhat.com&gt; Sent: Tuesday, July 31, 2012 10:36:45 PM Subject: Re: [Users] How to force VM's to run on different hosts? On 07/31/2012 10:20 PM, Maxim Burgerhout wrote: > Nice, thanks for the info. Can you give a hint of a time frame for > the > implementation? I'm not asking for dates or even version numbers, > just > something along the lines of 'short term', 'mid term', etc. I'd go with mid-term. (there is a POC patch for integrating drools which would allow you to write your own scheduling policies for something like that) http://gerrit.ovirt.org/#/c/6574/ several thoughts here: 1. need to add positive/negative affinity fields to VM entity. 2. make the scheduling logic a supported interface for pluggable implementations 3. implement the drool implementation as a pluggable implementation. 4. support affinity based scheduling #2 would allow someone to write their own scheduling logic in java code (well, maybe java wrapping/calling some other language). #3 would allow someone to write their own scheduling logic using rule based language with drools. #4 would mean you wouldn't need #2-#3 for this specific feature.

> > Regards, > > > Maxim Burgerhout > maxim(a)wzzrd.com <mailto:maxim@wzzrd.com> > ---------------- > EB11 5E56 E648 9D99 E8EF 05FB C513 6FD4 1302 B48A > > > > > On Tue, Jul 31, 2012 at 3:19 PM, Itamar Heim <iheim(a)redhat.com > <mailto:iheim@redhat.com>> wrote: > > On 07/31/2012 04:07 PM, Maxim Burgerhout wrote: > > Hi, > > Can someone tell me whether setting positive and negative > VM > affinity > rules will be at all possible with oVirt at some point in > time, > i.e. is > this on the roadmap? > > > it is. > > > I need to be able to tell VM's to run on different hosts, > spread > them > around, so to speak. For example, domain controllers would > be > better off > running on as many different hypervisors as possible, the > way I > see it. > That way, the failure of a single hypervisor has minimal > impact > on the > infrastructure. I know there is a feature to pin VM's to a > single > hypervisor, but that's not quite the same. I would like to > group the > domain controllers and then tell them not to run on the > same host as > other members of that group as much as possible. > > The other way around would be nice as well: have several > VM's > run on the > same hardware. For example, a three tiered web application > would > probably perform better if the VM's are all on the same > hypervisor. I > know I could pin them all to the same hypervisor, but > still: > that's not > quite the same. I want to be able to group the web app VM's > and tell > them to try to run on the same hypervisors as the other > members > of the > group, so they can move to another hypervisor as a group if > the > need arises. > > Apologies if this has been asked before or documented in > some > place I > haven't looked yet. > > > two ways for you to do this today: > 1. prefer/pin these VMs to different host > 2. use two clusters and put them in different ones > > Regards, > > Maxim Burgerhout<mailto:maxim@wzzrd.__com > <mailto:maxim@wzzrd.com>> > > > > > > _________________________________________________ > Users mailing list > Users(a)ovirt.org <mailto:Users@ovirt.org> > http://lists.ovirt.org/__mailman/listinfo/users > <http://lists.ovirt.org/mailman/listinfo/users> > > > >