NVIDIA Virtual GPU for KVM Guests #
1 Introduction #
NVIDIA virtual GPU (vGPU) is a graphics virtualization solution that provides multiple virtual machines (VMs) simultaneous access to one physical Graphics Processing Unit (GPU) on the VM Host Server. This article refers to the Volta and Ampere GPU architecture.
2 Configuring vGPU manager in VM Host Server #
2.1 Prepare VM Host Server environment #
Verify that you have a compatible server and GPU cards. Check specifications for details:
Verify that VM Host Server is SUSE Linux Enterprise Server 15 SP3 or newer:
>
cat /etc/issue Welcome to SUSE Linux Enterprise Server 15 SP3 (x86_64) - Kernel \r (\l).Get the vGPU drivers from NVIDIA. In order to get the software, please follow the steps at https://docs.nvidia.com/grid/latest/grid-software-quick-start-guide/index.html#redeeming-pak-and-downloading-grid-software. For example, for vGPU 13.0 installation, you will need the following files:
NVIDIA-Linux-x86_64-470.63-vgpu-kvm.run # vGPU manager for the VM host NVIDIA-Linux-x86_64-470.63.01-grid.run # vGPU driver for the VM guest
If you are using Ampere architecture GPU cards, verify that VM Host Server supports VT-D/IOMMU and SR-IOV technologies, and that they are enabled in BIOS.
Enable IOMMU. Verify that it is included in the boot command line:
cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-default [...] intel_iommu=on [...]
If not, add the following line to
/etc/default/grub
.For Intel CPUs:
GRUB_CMDLINE_LINUX="intel_iommu=on"
For AMD CPUs:
GRUB_CMDLINE_LINUX="amd_iommu=on"
Then generate new GRUB 2 configuration file and reboot:
>
sudo
grub2-mkconfig -o /boot/grub2/grub.cfg>
sudo
systemctl rebootTipYou can verify that IOMMU is loaded by running the following command:
sudo dmesg | grep -e IOMMU
Enable SR-IOV. Refer to https://docs.nvidia.com/grid/13.0/grid-vgpu-user-guide/index.html#vgpu-types-tesla-v100-pcie for useful information.
Disable the nouveau kernel module by adding the following line it to the top of the
/etc/modprobe.d/50-blacklist.conf
file:blacklist nouveau
2.2 Install the NVIDIA KVM driver #
Exit from the graphical mode:
>
sudo
init 3Install kernel-default-devel and gcc packages and their dependencies:
>
sudo
zypper in kernel-default-devel gccDownload the vGPU software from the NVIDIA portal. Make the NVIDIA vGPU driver executable and run it:
>
chmod +x NVIDIA-Linux-x86_64-450.55-vgpu-kvm.run>
sudo
./NVIDIA-Linux-x86_64-450.55-vgpu-kvm.runYou can find detailed information about the installation process in the log file
/var/log/nvidia-installer.log
TipTo enable dynamic kernel-module support, and thus have the module rebuilt automatically when new a new kernel is installed, add the
--dkms
option:>
sudo
./NVIDIA-Linux-x86_64-450.55-vgpu-kvm.run --dkmsWhen the driver installation is finished, reboot the system:
>
sudo
systemctl reboot
2.3 Verify the driver installation #
Verify loaded kernel modules:
>
lsmod | grep nvidia nvidia_vgpu_vfio 49152 9 nvidia 14393344 229 nvidia_vgpu_vfio mdev 20480 2 vfio_mdev,nvidia_vgpu_vfio vfio 32768 6 vfio_mdev,nvidia_vgpu_vfio,vfio_iommu_type1The modules containing the
vfio
string are required dependencies.Print the GPU device status with the
nvidia-smi
command. The output should be similar to the following one:>
nvidia-smi +-----------------------------------------------------------------------------+ | NVIDIA-SMI 470.63 Driver Version: 470.63 CUDA Version: N/A | |-------------------------------+----------------------+----------------------+ | GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC | | Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. | | | | MIG M. | |===============================+======================+======================| | 0 NVIDIA A40 Off | 00000000:31:00.0 Off | 0 | | 0% 46C P0 39W / 300W | 0MiB / 45634MiB | 0% Default | | | | N/A | +-------------------------------+----------------------+----------------------+ +-----------------------------------------------------------------------------+ | Processes: | | GPU GI CI PID Type Process name GPU Memory | | ID ID Usage | |=============================================================================| | No running processes found | +-----------------------------------------------------------------------------+Check the sysfs file system. For Volta and earlier GPU cards, new directory
mdev_supported_types
is added, for example:cd /sys/bus/pci/devices/00000000\:31\:00.0/mdev_supported_types
For Ampere GPU cards, the directory will be created automatically for each virtual function after SR-IOV is enabled.
3 Creating a vGPU device #
3.1 Create a legacy vGPU device without support for SR-IOV #
All the NVIDIA Volta and earlier architecture GPUs work in this mode.
Obtain the Bus/Device/Function (BDF) numbers of the host GPU device:
>
lspci | grep NVIDIA 84:00.0 3D controller: NVIDIA Corporation GV100GL [Tesla V100 PCIe 16GB] (rev a1)Check for the mdev supported devices and detailed information:
>
ls /sys/bus/pci/devices/0000:84:00.0/mdev_supported_types/ nvidia-105 nvidia-106 nvidia-107 nvidia-108 nvidia-109 nvidia-110 [...]The map of vGPU mdev devices and their type is as follows:
nvidia-105 to nvidia-109: 1Q 2Q 4Q 8Q 16Q
nvidia-110 to nvidia-114: 1A 2A 4A 8A 16A
nvidia-115, nvidia-163, nvidia-217, nvidia-247: 1B 2B 2B4 1B4
nvidia-299 to nvidia-301: 4C 8C 16C
Refer to https://docs.nvidia.com/grid/latest/grid-vgpu-user-guide/index.html#vgpu-types-tesla-v100-pcie for more details.
Inspect a vGPU device:
>
cd /sys/bus/pci/devices/0000:03:00.0/mdev_supported_types/>
ls nvidia-105>
cat nvidia-105/description num_heads=2, frl_config=60, framebuffer=1024M, max_resolution=4096x2160, max_instance=16>
cat nvidia-105/name GRID V100-1QGenerate a unique ID and create an mdev device based on it:
>
uuidgen 4f3b6e47-0baa-4900-b0b1-284c1ecc192f>
sudo
echo "4f3b6e47-0baa-4900-b0b1-284c1ecc192f" > nvidia-105/createVerify the new mdev device. You can inspect the content of the
/sys/bus/mdev/devices
directory:>
cd /sys/bus/mdev/devices>
ls -l lrwxrwxrwx 1 root root 0 Aug 30 23:03 86380ffb-8f13-4685-9c48-0e0f4e65fb87 \ -> ../../../devices/pci0000:80/0000:80:02.0/0000:84:00.0/86380ffb-8f13-4685-9c48-0e0f4e65fb87 lrwxrwxrwx 1 root root 0 Aug 30 23:03 86380ffb-8f13-4685-9c48-0e0f4e65fb88 \ -> ../../../devices/pci0000:80/0000:80:02.0/0000:84:00.0/86380ffb-8f13-4685-9c48-0e0f4e65fb88 lrwxrwxrwx 1 root root 0 Aug 30 23:03 86380ffb-8f13-4685-9c48-0e0f4e65fb89 \ -> ../../../devices/pci0000:80/0000:80:02.0/0000:84:00.0/86380ffb-8f13-4685-9c48-0e0f4e65fb89 lrwxrwxrwx 1 root root 0 Aug 30 23:03 86380ffb-8f13-4685-9c48-0e0f4e65fb90 \ -> ../../../devices/pci0000:80/0000:80:02.0/0000:84:00.0/86380ffb-8f13-4685-9c48-0e0f4e65fb90Or you can use the
mdevctl
command:>
sudo
mdevctl list 86380ffb-8f13-4685-9c48-0e0f4e65fb90 0000:84:00.0 nvidia-299 86380ffb-8f13-4685-9c48-0e0f4e65fb89 0000:84:00.0 nvidia-299 86380ffb-8f13-4685-9c48-0e0f4e65fb87 0000:84:00.0 nvidia-299 86380ffb-8f13-4685-9c48-0e0f4e65fb88 0000:84:00.0 nvidia-299Query the new vGPU device capability:
>
sudo
nvidia-smi vgpu -q GPU 00000000:84:00.0 Active vGPUs : 1 vGPU ID : 3251634323 VM UUID : ee7b7a4b-388a-4357-a425-5318b2c65b3f VM Name : sle15sp3 vGPU Name : GRID V100-4C vGPU Type : 299 vGPU UUID : d471c7f2-0a53-11ec-afd3-38b06df18e37 MDEV UUID : 86380ffb-8f13-4685-9c48-0e0f4e65fb87 Guest Driver Version : 460.91.03 License Status : Licensed GPU Instance ID : N/A Accounting Mode : Disabled ECC Mode : N/A Accounting Buffer Size : 4000 Frame Rate Limit : N/A FB Memory Usage Total : 4096 MiB Used : 161 MiB Free : 3935 MiB Utilization Gpu : 0 % Memory : 0 % Encoder : 0 % Decoder : 0 % Encoder Stats Active Sessions : 0 Average FPS : 0 Average Latency : 0 FBC Stats Active Sessions : 0 Average FPS : 0 Average Latency : 0
3.2 Create a vGPU device with support for SR-IOV #
All NVIDIA Ampere and newer architecture GPUs work in this mode.
Obtain the Bus/Device/Function (BDF) numbers of the host GPU device:
>
lspci | grep NVIDIA b1:00.0 3D controller: NVIDIA Corporation GA100 [A100 PCIe 40GB] (rev a1)Enable virtual functions:
>
sudo
/usr/lib/nvidia/sriov-manage -e 00:b1:0000.0NoteThis configuration is not persistent and must be re-enabled after the host reboot.
Obtain the Bus/Domain/Function (BDF) of virtual functions on the GPU:
>
ls -l /sys/bus/pci/devices/0000:b1:00.0/ | grep virtfn lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn0 -> ../0000:b1:00.4 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn1 -> ../0000:b1:00.5 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn10 -> ../0000:b1:01.6 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn11 -> ../0000:b1:01.7 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn12 -> ../0000:b1:02.0 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn13 -> ../0000:b1:02.1 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn14 -> ../0000:b1:02.2 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn15 -> ../0000:b1:02.3 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn2 -> ../0000:b1:00.6 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn3 -> ../0000:b1:00.7 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn4 -> ../0000:b1:01.0 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn5 -> ../0000:b1:01.1 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn6 -> ../0000:b1:01.2 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn7 -> ../0000:b1:01.3 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn8 -> ../0000:b1:01.4 lrwxrwxrwx 1 root root 0 Sep 21 11:58 virtfn9 -> ../0000:b1:01.5Create a vGPU device. Select the virtual function (VF) that you want to use to create the vGPU device and assign it a unique ID.
ImportantEach VF can only create one vGPU instance. If you want to create more vGPU instances, you need to use a different VF.
>
cd /sys/bus/pci/devices/0000:b1:00.0/virtfn1/mdev_supported_types>
for i in *; do echo "$i" $(cat $i/name) available: $(cat $i/avail*); done nvidia-468 GRID A100-4C available: 0 nvidia-469 GRID A100-5C available: 0 nvidia-470 GRID A100-8C available: 0 nvidia-471 GRID A100-10C available: 1 nvidia-472 GRID A100-20C available: 0 nvidia-473 GRID A100-40C available: 0 nvidia-474 GRID A100-1-5C available: 0 nvidia-475 GRID A100-2-10C available: 0 nvidia-476 GRID A100-3-20C available: 0 nvidia-477 GRID A100-4-20C available: 0 nvidia-478 GRID A100-7-40C available: 0 nvidia-479 GRID A100-1-5CME available: 0>
uuidgen f715f63c-0d00-4007-9c5a-b07b0c6c05de>
sudo
echo "f715f63c-0d00-4007-9c5a-b07b0c6c05de" > nvidia-471/create>
sudo
dmesg | tail [...] [ 3218.491843] vfio_mdev f715f63c-0d00-4007-9c5a-b07b0c6c05de: Adding to iommu group 322 [ 3218.499700] vfio_mdev f715f63c-0d00-4007-9c5a-b07b0c6c05de: MDEV: group_id = 322 [ 3599.608540] vfio_mdev f715f63c-0d00-4007-9c5a-b07b0c6c05de: Removing from iommu group 322 [ 3599.616753] vfio_mdev f715f63c-0d00-4007-9c5a-b07b0c6c05de: MDEV: detaching iommu [ 3626.345530] vfio_mdev f715f63c-0d00-4007-9c5a-b07b0c6c05de: Adding to iommu group 322 [ 3626.353383] vfio_mdev f715f63c-0d00-4007-9c5a-b07b0c6c05de: MDEV: group_id = 322Verify the new vGPU device:
>
cd /sys/bus/mdev/devices/>
ls f715f63c-0d00-4007-9c5a-b07b0c6c05deQuery the new vGPU device capability:
>
sudo
nvidia-smi vgpu -q GPU 00000000:B1:00.0 Active vGPUs : 1 vGPU ID : 3251634265 VM UUID : b0d9f0c6-a6c2-463e-967b-06cb206415b6 VM Name : sles15sp2-gehc-vm1 vGPU Name : GRID A100-10C vGPU Type : 471 vGPU UUID : 444f610c-1b08-11ec-9554-ebd10788ee14 MDEV UUID : f715f63c-0d00-4007-9c5a-b07b0c6c05de Guest Driver Version : N/A License Status : N/A GPU Instance ID : N/A Accounting Mode : N/A ECC Mode : Disabled Accounting Buffer Size : 4000 Frame Rate Limit : N/A FB Memory Usage Total : 10240 MiB Used : 0 MiB Free : 10240 MiB Utilization Gpu : 0 % Memory : 0 % Encoder : 0 % Decoder : 0 % Encoder Stats Active Sessions : 0 Average FPS : 0 Average Latency : 0 FBC Stats Active Sessions : 0 Average FPS : 0 Average Latency : 0
3.3 Creating a MIG-backed vGPU #
SR-IOV is required to be enabled if you want to create vGPUs and assign them to guest VMs.
Enable MIG mode for a GPU:
>
sudo
nvidia-smi -i 0 -mig 1 Enabled MIG Mode for GPU 00000000:B1:00.0 All done.Query the GPU instance profile:
>
sudo
nvidia-smi mig -lgip +-----------------------------------------------------------------------------+ | GPU instance profiles: | | GPU Name ID Instances Memory P2P SM DEC ENC | | Free/Total GiB CE JPEG OFA | |=============================================================================| | 0 MIG 1g.5gb 19 7/7 4.75 No 14 0 0 | | 1 0 0 | +-----------------------------------------------------------------------------+ | 0 MIG 1g.5gb+me 20 1/1 4.75 No 14 1 0 | | 1 1 1 | +-----------------------------------------------------------------------------+ | 0 MIG 2g.10gb 14 3/3 9.75 No 28 1 0 | | 2 0 0 | +-----------------------------------------------------------------------------+ | 0 MIG 3g.20gb 9 2/2 19.62 No 42 2 0 | | 3 0 0 | +-----------------------------------------------------------------------------+ | 0 MIG 4g.20gb 5 1/1 19.62 No 56 2 0 | | 4 0 0 | +-----------------------------------------------------------------------------+ | 0 MIG 7g.40gb 0 1/1 39.50 No 98 5 0 | | 7 1 1 | +-----------------------------------------------------------------------------+Create a GPU instance specifying '5' as a GPU profile instance ID and optionally create a Compute Instance on it, either on the host server or within the guest:
>
sudo
nvidia-smi mig -cgi 5 Successfully created GPU instance ID 1 on GPU 0 using profile MIG 4g.20gb (ID 5)>
sudo
nvidia-smi mig -cci -gi 1 Successfully created compute instance ID 0 on GPU 0 GPU instance ID 1 using profile MIG 4g.20gb (ID 3)Verify the GPU instance:
>
sudo
nvidia-smi Tue Sep 21 11:19:36 2021 +-----------------------------------------------------------------------------+ | NVIDIA-SMI 470.63 Driver Version: 470.63 CUDA Version: N/A | |-------------------------------+----------------------+----------------------+ | GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC | | Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. | | | | MIG M. | |===============================+======================+======================| | 0 NVIDIA A100-PCI... On | 00000000:B1:00.0 Off | On | | N/A 38C P0 38W / 250W | 0MiB / 40536MiB | N/A Default | | | | Enabled | +-------------------------------+----------------------+----------------------+ +-----------------------------------------------------------------------------+ | MIG devices: | +------------------+----------------------+-----------+-----------------------+ | GPU GI CI MIG | Memory-Usage | Vol| Shared | | ID ID Dev | BAR1-Usage | SM Unc| CE ENC DEC OFA JPG| | | | ECC| | |==================+======================+===========+=======================| | 0 1 0 0 | 0MiB / 20096MiB | 56 0 | 4 0 2 0 0 | | | 0MiB / 32767MiB | | | +------------------+----------------------+-----------+-----------------------+ +-----------------------------------------------------------------------------+ | Processes: | | GPU GI CI PID Type Process name GPU Memory | | ID ID Usage | |=============================================================================| | No running processes found | +-----------------------------------------------------------------------------+Use the MIG instance. You can use the instance directly with the UUID—for example, assign it to a container or CUDA process.
You can also create a vGPU on top of it and assign it to a VM guest. The procedure is the same as for the vGPU with SR-IOV support. Refer to Section 3.2, “Create a vGPU device with support for SR-IOV”.
>
sudo
nvidia-smi -L GPU 0: NVIDIA A100-PCIE-40GB (UUID: GPU-ee14e29d-dd5b-2e8e-eeaf-9d3debd10788) MIG 4g.20gb Device 0: (UUID: MIG-fed03f85-fd95-581b-837f-d582496d0260)
4 Assign the vGPU device to a VM Guest #
4.1 Assign by libvirt
#
Create a
libvirt
-based virtual machine (VM) with UEFI support and a normal VGA display.Edit the VM's configuration by running
virsh edit VM-NAME
.Add the new mdev device with the unique ID you used when creating the vGPU device to the <devices/> section.
NoteIf you are using Q-series, use
display='on'
instead.<hostdev mode='subsystem' type='mdev' managed='no' model='vfio-pci' display='off'> <source> <address uuid='4f3b6e47-0baa-4900-b0b1-284c1ecc192f'/> </source> <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/> </hostdev>
4.2 Assign by QEMU #
Add the following device to the QEMU command line. Use the unique ID that you used when creating the vGPU device:
-device vfio-pci,sysfsdev=/sys/bus/mdev/devices/4f3b6e47-0baa-4900-b0b1-284c1ecc192f
5 Configuring vGPU in VM Guest #
5.1 Prepare the VM Guest #
During VM Guest installation, disable secure boot, enable the SSH service, and select
wicked
for networking.Disable the
nouveau
video driver. Edit the file/etc/modprobe.d/50-blacklist.conf
and add the following line to its upper section:blacklist nouveau
ImportantDisabling
nouveau
will work after you re-generate the initrd image with mkinitrd, and then reboot the VM Guest.
5.2 Install the vGPU driver in the VM Guest #
Install the following packages and their dependencies:
>
sudo
zypper install kernel-default-devel libglvnd-develDownload the vGPU software from the NVIDIA portal. Make the NVIDIA vGPU driver executable and run it:
>
chmod +x NVIDIA-Linux-x86_64-470.63.01-grid.run>
sudo
./NVIDIA-Linux-x86_64-470.63.01-grid.runTipTo enable dynamic kernel module support in order to get the module rebuilt automatically when new a new kernel is installed, add the
--dkms
option:>
sudo
./NVIDIA-Linux-x86_64-470.63.01-grid.run --dkmsDuring driver installation, select to run the
nvidia-xconfig
utility.Verify the driver installation by checking the output of the
nvidia-smi
command:>
sudo
nvidia-smi +-----------------------------------------------------------------------------+ | NVIDIA-SMI 470.63.01 Driver Version: 470.63.01 CUDA Version: 11.4 | |-------------------------------+----------------------+----------------------+ | GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC | | Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. | | | | MIG M. | |===============================+======================+======================| | 0 GRID A100-10C On | 00000000:07:00.0 Off | 0 | | N/A N/A P0 N/A / N/A | 930MiB / 10235MiB | 0% Default | | | | Disabled | +-------------------------------+----------------------+----------------------+ +-----------------------------------------------------------------------------+ | Processes: | | GPU GI CI PID Type Process name GPU Memory | | ID ID Usage | |=============================================================================| | No running processes found | +-----------------------------------------------------------------------------+
6 Licensing vGPU in the VM Guest #
Create the configuration file
/etc/nvidia/gridd.conf
based on/etc/nvidia/gridd.conf.template
.For licenses that are served from the NVIDIA License System, update the following options:
- FeatureType
For GPU passthrough, set
FeatureType
to4
for computing and2
for graphic purposes. In case of a virtual GPU, whatever vGPU type is created viamdev
determines the feature set that is enabled in VM Guest.- ClientConfigTokenPath
Optional: If you want to store the client configuration token in a custom location, add the
ClientConfigTokenPath
configuration parameter on a new line asClientConfigTokenPath="PATH_TO_TOKEN"
. By default, the client searches for the client configuration token in the/etc/nvidia/ClientConfigToken/
directory.Copy the client configuration token to the directory in which you want to store it.
For licenses that are served from the legacy NVIDIA vGPU software license server, update the following options:
- ServerAddress
Add your license server IP address.
- ServerPort
Use the default "7070" or the port configured during the server setup.
- FeatureType
For GPU passthrough, set
FeatureType
to4
for computing and2
for graphic purposes. In case of a virtual GPU, whatever vGPU type is created viamdev
determines the feature set that is enabled in VM Guest.
Restart the
nvidia-gridd
service:>
sudo
systemctl restart nvidia-gridd.serviceInspect the log file for possible errors:
>
sudo
grep gridd /var/log/messages [...] Aug 5 15:40:06 localhost nvidia-gridd: Started (4293) Aug 5 15:40:24 localhost nvidia-gridd: License acquired successfully.
7 Configuring a graphics mode #
7.1 Create or update the /etc/X11/xorg.conf
file #
If there is no
/etc/X11/xorg.conf
on the VM Guest, run thenvidia-xconfig
utility.Query the GPU device for detailed information:
>
nvidia-xconfig --query-gpu-info Number of GPUs: 1 GPU #0: Name : GRID V100-16Q UUID : GPU-089f39ad-01cb-11ec-89dc-da10f5778138 PCI BusID : PCI:0:10:0 Number of Display Devices: 0Add GPU's BusID to
/etc/X11/xorg.conf
, for example:Section "Device" Identifier "Device0" Driver "nvidia" BusID "PCI:0:10:0" VendorName "NVIDIA Corporation" EndSection
7.2 Verify the graphics mode #
Verify the following:
A graphic desktop is booted correctly.
The 'X' process of a running X-server is running in GPU:
>
nvidia-smi +-----------------------------------------------------------------------------+ | NVIDIA-SMI 470.63.01 Driver Version: 470.63.01 CUDA Version: 11.4 | |-------------------------------+----------------------+----------------------+ | GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC | | Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. | | | | MIG M. | |===============================+======================+======================| | 0 GRID V100-4C On | 00000000:00:0A.0 Off | N/A | | N/A N/A P0 N/A / N/A | 468MiB / 4096MiB | 0% Default | | | | N/A | +-------------------------------+----------------------+----------------------+ +-----------------------------------------------------------------------------+ | Processes: | | GPU GI CI PID Type Process name GPU Memory | | ID ID Usage | |=============================================================================| | 0 N/A N/A 1921 G /usr/bin/X 76MiB | | 0 N/A N/A 1957 G /usr/bin/gnome-shell 87MiB | +-----------------------------------------------------------------------------+
7.3 Remote display #
You need to install and configure the VNC server package x11vnc inside the VM Guest, and start it with the following command:
>
sudo
x11vnc -display :0 -auth /run/user/1000/gdm/Xauthority -forever -shared -ncache -bg -usepw -geometry 1900x1080
You can use virt-manager
or
virt-viewer
to display the graphical output of a
VM Guest.
For a libvirt
-based VM Guest, verify that its XML configuration
includes display=on
as suggested in
Section 4.1, “Assign by libvirt
”.
8 Configuring compute mode #
Download and install the CUDA toolkit. You can find it at https://developer.nvidia.com/cuda-downloads?target_os=Linux&target_arch=x86_64&Distribution=SLES&target_version=15&target_type=runfile_local.
Download CUDA samples from https://github.com/nvidia/cuda-samples.
Run CUDA sampling example:
>
cd YOUR_GIT_CLONE_LOCATION/cuda-samples/Samples/0_Introduction/clock>
make /usr/local/cuda/bin/nvcc -ccbin g++ -I../../common/inc -m64 --threads 0 -gencode arch=compute_35,code=sm_35 -gencode arch=compute_37,code=sm_37 -gencode [...] mkdir -p ../../bin/x86_64/linux/release cp clock ../../bin/x86_64/linux/release>
./clock CUDA Clock sample GPU Device 0: "Volta" with compute capability 7.0 Average clocks/block = 2820.718750
9 Additional tasks #
This section introduces additional procedures that may be helpful after you have configured your vGPU.
9.1 Disabling Frame Rate Limiter #
Frame Rate Limiter (FRL) is enabled by default. It limits the vGPU to a fixed frame rate , for example 60fps. If you experience a bad graphic display, you may need to disable FRL, for example:
>
sudo
echo "frame_rate_limiter=0" > /sys/bus/mdev/devices/86380ffb-8f13-4685-9c48-0e0f4e65fb87/nvidia/vgpu_params
9.2 Enabling/Disabling Error Correcting Code (ECC) #
Since the NVIDIA Pascal architecture, NVIDIA GPU Cards support ECC memory to improve data integrity. ECC is also supported by software since NVIDIA vGPU 9.0.
To enable ECC:
>
sudo
nvidia-smi –e 1>
nvidia-smi -q Ecc Mode Current : Enabled Pending : Enabled
To disable ECC:
>
sudo
nvidia-smi –e 0
9.3 Black screen in Virt-manager #
If you see only a black screen in Virt-manager, press Alt–Ctrl–2 from Virt-manager viewer. You should be able to get in the display again.
9.4 Black screen in VNC client when using a non-QEMU VNC server #
Use the xvnc server.
9.5 Kernel panic occurs because the Nouveau and NVIDIA drivers compete on GPU resources #
The boot messages will look as follows:
[ 16.742439] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 16.742441] RIP: 0010:__pci_enable_msi_range+0x3a9/0x3f0 [ 16.742443] Code: 76 60 49 8d 56 50 48 89 df e8 73 f6 fc ff e9 3b fe ff ff 31 f6 48 89 df e8 64 73 fd ff e9 d6 fe ff ff 44 89 fd e9 1a ff ff ff <0f> 0b bd ea ff ff ff e9 0e ff ff ff bd ea ff ff ff e9 04 ff f f ff [ 16.742444] RSP: 0018:ffffb04bc052fb28 EFLAGS: 00010202 [ 16.742445] RAX: 0000000000000010 RBX: ffff9e93a85bc000 RCX: 0000000000000001 [ 16.742457] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9e93a85bc000 [ 16.742458] RBP: ffff9e93a2550800 R08: 0000000000000002 R09: ffffb04bc052fb1c [ 16.742459] R10: 0000000000000050 R11: 0000000000000020 R12: ffff9e93a2550800 [ 16.742459] R13: 0000000000000001 R14: ffff9e93a2550ac8 R15: 0000000000000001 [ 16.742460] FS: 00007f9f26889740(0000) GS:ffff9e93bfdc0000(0000) knlGS:0000000000000000 [ 16.742461] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 16.742462] CR2: 00000000008aeb90 CR3: 0000000286470003 CR4: 0000000000170ee0 [ 16.742465] Call Trace: [ 16.742503] ? __pci_find_next_cap_ttl+0x93/0xd0 [ 16.742505] pci_enable_msi+0x16/0x30 [ 16.743039] nv_init_msi+0x1a/0xf0 [nvidia] [ 16.743154] nv_open_device+0x81b/0x890 [nvidia] [ 16.743248] nvidia_open+0x2f7/0x4d0 [nvidia] [ 16.743256] ? kobj_lookup+0x113/0x160 [ 16.743354] nvidia_frontend_open+0x53/0x90 [nvidia] [ 16.743361] chrdev_open+0xc4/0x1a0 [ 16.743370] ? cdev_put.part.2+0x20/0x20 [ 16.743374] do_dentry_open+0x204/0x3a0 [ 16.743378] path_openat+0x2fc/0x1520 [ 16.743382] ? unlazy_walk+0x32/0xa0 [ 16.743383] ? terminate_walk+0x8c/0x100 [ 16.743385] do_filp_open+0x9b/0x110 [ 16.743387] ? chown_common+0xf7/0x1c0 [ 16.743390] ? kmem_cache_alloc+0x18a/0x270 [ 16.743392] ? do_sys_open+0x1bd/0x260 [ 16.743394] do_sys_open+0x1bd/0x260 [ 16.743400] do_syscall_64+0x5b/0x1e0 [ 16.743409] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 16.743418] RIP: 0033:0x7f9f2593961d [ 16.743420] Code: f0 25 00 00 41 00 3d 00 00 41 00 74 48 64 8b 04 25 18 00 00 00 85 c0 75 64 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 0f 87 97 00 00 00 48 8b 4c 24 28 64 48 33 0 c 25 [ 16.743420] RSP: 002b:00007ffcfa214930 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 [ 16.743422] RAX: ffffffffffffffda RBX: 00007ffcfa214c30 RCX: 00007f9f2593961d [ 16.743422] RDX: 0000000000080002 RSI: 00007ffcfa2149b0 RDI: 00000000ffffff9c [ 16.743423] RBP: 00007ffcfa2149b0 R08: 0000000000000000 R09: 0000000000000000 [ 16.743424] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 16.743424] R13: 00007ffcfa214abc R14: 0000000000925ae0 R15: 0000000000000000 [ 16.743426] ---[ end trace 8bf4d15315659a3e ]--- [ 16.743431] NVRM: GPU 0000:00:0a.0: Failed to enable MSI; falling back to PCIe virtual-wire interrupts.
Make sure to run mkintrd
and reboot after disabling the
Nouveau driver. Refer to
Section 5.1, “Prepare the VM Guest”.
9.6 Filing an NVIDIA vGPU bug #
While filing an NVIDIA vGPU-related bug report to us, please attach the
vGPU configuration data nvidia-bug-report.log.gz
collected by the nvidia-bug-report.sh
utility. Make sure
you cover both VM Host Server and VM Guest.
9.7 Configuring a License Server #
Refer to https://docs.nvidia.com/grid/ls/latest/grid-license-server-user-guide/index.html.
10 For more information #
NVIDIA has an extensive documentation on vGPU. Refer to https://docs.nvidia.com/grid/latest/grid-vgpu-user-guide/index.html for details.
11 NVIDIA virtual GPU background #
11.1 NVIDIA GPU architectures #
There are two types of GPU architectures:
- Time-sliced vGPU architecture
Introduced on GPUs that are based on the NVIDIA Ampere GPU architecture. Only Ampere GPU cards can support MIG-backed vGPU.
Figure 1: Time-sliced architecture (source: https://docs.nvidia.com/grid/latest/grid-vgpu-user-guide/index.html) #- Multi-Instance GPU (MIG) vGPU architecture
All GPU cards support time-sliced vGPU. To do so, Ampere GPU cards use the Single Root I/O Virtualization (SR-IOV) mechanism, while Volta and the earlier GPU cards use the mediated device mechanism. Volta and the earlier architecture are based on mediated device mechanism. These two mechanisms are transparent to a VM. However, they need different configurations from the host side.
Figure 2: MIG-backed architecture (source: https://docs.nvidia.com/grid/latest/grid-vgpu-user-guide/index.html) #
11.2 vGPU types #
Each physical GPU can support several different types of vGPUs. vGPU types have a fixed amount of frame buffer, the number of supported display heads, and maximum resolutions. NVIDIA has four types of vGPUs: A, B, C, and Q-series. SUSE currently supports Q and C-series.
vGPU series |
Optimal workload |
---|---|
Q-series |
Virtual workstations for creative and technical professionals who require the performance and features of the NVIDIA Quadro technology. |
C-series |
Compute-intensive server workloads, for example, artificial intelligence (AI), deep learning, or high-performance computing (HPC). |
B-series |
Virtual desktops for business professionals and knowledge workers. |
A-series |
Application streaming or session-based solutions for virtual applications users. |
11.3 Valid vGPU configurations on a single GPU #
11.3.1 Time-sliced vGPU configurations #
For time-sliced vGPUs, all vGPUs types must be the same:
11.3.2 MIG-backed vGPU configurations #
For MIG-backed vGPUs, vGPUs can be both homogeneous and mixed-type:
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