[ClusterLabs] resource location preference vs utilization

[Ken Gaillot]

On Mon, 2019-07-15 at 18:41 +0200, wferi at niif.hu wrote:
> Hi,
> 
> In a mostly symmetrical cluster I've got a couple of resources which
> should only ever run on a subset of the nodes if possible.  However,
> utilization constraints seem to prevent optimal resource allocation
> in
> some cases: Pacemaker does not migrate other resources to make room
> for
> the picky resources on their preferred nodes.  Is there a way around
> this?  The score differences are way above the resource stickiness,
> and
> as soon as I manually move enough indifferent resources away from the
> distinguished nodes, Pacemaker indeed migrates the picky resources
> over
> to them.  Can I configure it to also make room automatically by
> moving
> other resources as necessary, making this process fully automatic?

I'm not aware of any knobs to turn to affect that. Have you tried
putting small negative location constraints for the non-picky resources
on those nodes? Also, you could try putting a smaller stickiness on the
non-picky resources (I don't know whether that will have any effect,
just trying to think of ideas).
-- 
Ken Gaillot <kgaillot at redhat.com>