----- Original Message -----
From: "Itamar Heim" <iheim(a)redhat.com>
To: "Maxim Burgerhout" <maxim(a)wzzrd.com>
Cc: users(a)ovirt.org, "Laszlo Hornyak" <lhornyak(a)redhat.com>, "Doron
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
> implementation? I'm not asking for dates or even version numbers,
> 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)
several thoughts here:
1. need to add positive/negative affinity fields to VM entity.
2. make the scheduling logic a supported interface for pluggable
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
(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.
Note that the POC Itamar referred to works with Planner,
which is really nice, but will change in the future. That
said, I agree that VM affinity and negative affinity is
definitely in oVirt's roadmap.
> Maxim Burgerhout
> maxim(a)wzzrd.com <mailto:firstname.lastname@example.org>
> 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:email@example.com>> wrote:
> On 07/31/2012 04:07 PM, Maxim Burgerhout wrote:
> Can someone tell me whether setting positive and negative
> rules will be at all possible with oVirt at some point in
> i.e. is
> this on the roadmap?
> it is.
> I need to be able to tell VM's to run on different hosts,
> around, so to speak. For example, domain controllers would
> 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
> on the
> infrastructure. I know there is a feature to pin VM's to a
> 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
> run on the
> same hardware. For example, a three tiered web application
> 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
> 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
> of the
> group, so they can move to another hypervisor as a group if
> need arises.
> Apologies if this has been asked before or documented in
> 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
> Maxim Burgerhout<mailto:maxim@wzzrd.__com
> Users mailing list
> Users(a)ovirt.org <mailto:Users@ovirt.org>