I am already using aggregates to manage the scheduling, but I can't see how this can address my issue (I want that there is always room for the instantiation of a VM with flavor F) 

Cheers, Massimo

On Tue, Jan 7, 2025 at 2:14 PM Ali Basafa <alibasafa18@gmail.com> wrote:

Hi dear
If you wanna handle schedule of the instance you can use aggregate
For example you can create two aggregate for gpu and general then add computes to aggregate then create flavor for aggregates and add policy in property after that when create instance with flavor of gpu the instace schdule just to gpu computes

https://docs.openstack.org/python-openstackclient/pike/cli/command-objects/aggregate.html

On Tue, Jan 7, 2025, 4:34 PM Massimo Sgaravatto <massimo.sgaravatto@gmail.com> wrote:

Dear all

I have the following use case:

I defined a flavor F for VMS with 10 VCPUs, 20 GB of RAM, 30 GB of root disk,
1 GPU XYZ.


I use PCI passthrough to manage GPUs.

I have only a XYZ GPU on my cluster (on a H hypervisor), so a VM using this
flavor F must be "placed" to the compute node H (and this is not a problem: I
know how to do that).

H is very large: it has a lot of RAM and cores, so it can host
other VMs that do not use GPUs.

How can I make it so that VMs without GPU can go on H, but there must be room
for a VM with flavor F (if it doesn't already exist)?

Thanks, and happy new year !

Cheers, Massimo