[placement][ptg] Allocation Partitioning
On Apr 10, 2019, at 4:41 AM, Jay Pipes <jaypipes at gmail.com> wrote:
> I suppose what you're trying to determine is whether there is a viable use case for answering the question "given a single 'source partition' -- say, "my compute cloud region A" -- show me the usage of VCPU resources in my 'nova' compute hosts and my 'non-nova' compute hosts".
> I'm just not sure there's a viable use case there.
I was thinking more of the use case where there are several systems (novas) creating resource providers in a single placement service, and one of the novas asks for resources for an instance. We would need something equivalent to a per-nova aggregate so that placement doesn't return RPs from one of the other novas. Of course, requiring an agg to be manually set would not be practical, so some sort of automatic sharding identifier would be required.
I have no idea how to do this best, or even if this is a use case we want to be able to entertain. It might be sufficient to just say that separate systems that don't share resources should have their own placement.
-- Ed Leafe