NVIDIA GPU Changing Slot ID

[Neil68]

I have a server running Proxmox that I set up a VM on to run Ollama. I went through the GPU passthrough configuration and everything was working great. This was running for almost a month. Then I decided to add another VM to the server running CodeProject.AI and also passthrough the GPU. I found that I can't run two VM's using the same GPU when I tried to start the CodeProject.AI server. I then shutdown the Ollama server so that I could use the GPU to work on the CodeProject.AI server. After running into issues with that, I shut it down and was using the Ollama server and noticed it was running slow. After some investigation I discovered that it was no longer using the GPU. In the hardware configuration for the VM it shows as having slot ID 42 but when I run the NVIDIA utility in the VM, it is showing as slot ID 01 and Off. I also tried shutting down the Ollama server and checking the CodeProject.AI server which is also showing slot ID 01. I have tried several things with the hardware configuration and checking the installation of the drivers/utilities for the GPU with no luck. I'm not sure what would be useful since I'm new to Proxmox, but here is my system info:

Dell PowerEdge R720
2 x Intel Xeon E5-2680v2@2.8 GHz
384 GB ECC RAM
500 GB SSD
NVIDIA Tesla P40 in PCIe slot 4
Proxmox VE 8.2.4
Ollama server is running PopOS
CodeProject.AI server is running Ubuntu 24.04.1 LTS

Any help or suggestions would be greatly appreciated.

 

[Pifouney]

nothing abnormal with the 01 ID in yours VM => You 've only passed trough One hardware, so he's only using the first ID slot.

Passing trough = > Dedicating the hardware defined for be only visible in the VM used for. 2 VMs cannot share in the same time the same consumer GPU.

For reset any kind of hardware cache, reboot your Hypervisor and test performance in Ollama. If good now, shutdown it. Then, start your another VM, and check if running well.
If not, compare cfg of your 2 VM. Maybe a bad VM type or bad BIOs type.
For passing trough, UEFI needed, q35-machine type too.