Hi Massimo,

Ignore my last email, my requirement is to have a single VM with a
single GPU ("tesla-v100:1")  but I would like to create a second VM on
the same compute node which uses the second GPU but I am getting the
following error when I create a second VM and vm error out. looks like
it's not allowing me to create a second vm and bind to a second GPU
card.

error : virDomainDefDuplicateHostdevInfoValidate:1082 : XML error:
Hostdev already exists in the domain configuration

On Wed, Jan 19, 2022 at 3:10 PM Satish Patel <satish.txt@gmail.com> wrote:
>
> should i need to create a flavor to target both GPU. is it possible to
> have single flavor cover both GPU because end users don't understand
> which flavor to use.
>
> On Wed, Jan 19, 2022 at 1:54 AM Massimo Sgaravatto
> <massimo.sgaravatto@gmail.com> wrote:
> >
> > If I am not wrong those are 2 GPUs
> >
> > "tesla-v100:1" means 1 GPU
> >
> > So e.g. a flavor with "pci_passthrough:alias": "tesla-v100:2"} will be used to create an instance with 2 GPUs
> >
> > Cheers, Massimo
> >
> > On Tue, Jan 18, 2022 at 11:35 PM Satish Patel <satish.txt@gmail.com> wrote:
> >>
> >> Thank you for the information.  I have a quick question.
> >>
> >> [root@gpu01 ~]# lspci | grep -i nv
> >> 5e:00.0 3D controller: NVIDIA Corporation GV100GL [Tesla V100S PCIe
> >> 32GB] (rev a1)
> >> d8:00.0 3D controller: NVIDIA Corporation GV100GL [Tesla V100S PCIe
> >> 32GB] (rev a1)
> >>
> >> In the above output showing two cards does that mean they are physical
> >> two or just BUS representation.
> >>
> >> Also i have the following entry in openstack flavor, does :1 means
> >> first GPU card?
> >>
> >> {"gpu-node": "true", "pci_passthrough:alias": "tesla-v100:1"}
> >>
> >>
> >>
> >>
> >>
> >>
> >> On Tue, Jan 18, 2022 at 5:55 AM António Paulo <antonio.paulo@cern.ch> wrote:
> >> >
> >> > Hey Satish, Gustavo,
> >> >
> >> > Just to clarify a bit on point 3, you will have to buy a vGPU license
> >> > per card and this gives you access to all the downloads you need through
> >> > NVIDIA's web dashboard -- both the host and guest drivers as well as the
> >> > license server setup files.
> >> >
> >> > Cheers,
> >> > António
> >> >
> >> > On 18/01/22 02:46, Satish Patel wrote:
> >> > > Thank you so much! This is what I was looking for. It is very odd that
> >> > > we buy a pricey card but then we have to buy a license to make those
> >> > > features available.
> >> > >
> >> > > On Mon, Jan 17, 2022 at 2:07 PM Gustavo Faganello Santos
> >> > > <gustavofaganello.santos@windriver.com> wrote:
> >> > >>
> >> > >> Hello, Satish.
> >> > >>
> >> > >> I've been working with vGPU lately and I believe I can answer your
> >> > >> questions:
> >> > >>
> >> > >> 1. As you pointed out in question #2, the pci-passthrough will allocate
> >> > >> the entire physical GPU to one single guest VM, while vGPU allows you to
> >> > >> spawn from 1 to several VMs using the same physical GPU, depending on
> >> > >> the vGPU type you choose (check NVIDIA docs to see which vGPU types the
> >> > >> Tesla V100 supports and their properties);
> >> > >> 2. Correct;
> >> > >> 3. To use vGPU, you need vGPU drivers installed on the platform where
> >> > >> your deployment of OpenStack is running AND in the VMs, so there are two
> >> > >> drivers to be installed in order to use the feature. I believe both of
> >> > >> them have to be purchased from NVIDIA in order to be used, and you would
> >> > >> also have to deploy an NVIDIA licensing server in order to validate the
> >> > >> licenses of the drivers running in the VMs.
> >> > >> 4. You can see what the instructions are for each of these scenarios in
> >> > >> [1] and [2].
> >> > >>
> >> > >> There is also extensive documentation on vGPU at NVIDIA's website [3].
> >> > >>
> >> > >> [1] https://docs.openstack.org/nova/wallaby/admin/virtual-gpu.html
> >> > >> [2] https://docs.openstack.org/nova/wallaby/admin/pci-passthrough.html
> >> > >> [3] https://docs.nvidia.com/grid/13.0/index.html
> >> > >>
> >> > >> Regards,
> >> > >> Gustavo.
> >> > >>
> >> > >> On 17/01/2022 14:41, Satish Patel wrote:
> >> > >>> [Please note: This e-mail is from an EXTERNAL e-mail address]
> >> > >>>
> >> > >>> Folk,
> >> > >>>
> >> > >>> We have Tesla V100 32G GPU and I’m trying to configure with openstack wallaby. This is first time dealing with GPU so I have couple of question.
> >> > >>>
> >> > >>> 1. What is the difference between passthrough vs vGPU? I did google but not very clear yet.
> >> > >>> 2. If I configure it passthrough then does it only work with single VM ? ( I meant whole GPU will get allocate to single VM correct?
> >> > >>> 3. Also some document saying Tesla v100 support vGPU but some folks saying you need license. I have no idea where to get that license. What is the deal here?
> >> > >>> 3. What are the config difference between configure this card with passthrough vs vGPU?
> >> > >>>
> >> > >>>
> >> > >>> Currently I configure it with passthrough based one one article and I am able to spun up with and I can see nvidia card exposed to vm. (I used iommu and vfio based driver) so if this card support vGPU then do I need iommu and vfio or some other driver to make it virtualize ?
> >> > >>>
> >> > >>> Sent from my iPhone
> >> > >>>
> >> > >
> >>