Problem with GPU sharing

ADAKServer

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Oct 24, 2019
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Hi guys,
I want to share my GPU (Nvidia Geforce GTX 1080) between all of my VMs but the amount of shared GPU memory is 512MB but I want to increase this limit to 8GB!
Can anyone help me?
 
Are you referring to the "memory" parameters under "Hardware -> Display"? If so, that is not used for sharing GPU memory, it is just the buffer size of VRAM to allocate in main memory ("RAM") for the VM's emulated GPU.

You cannot "share" a GPU that easily, VMs will either use emulated graphics (which mostly run on the CPU) or you can assign an entire GPU via PCIe passthrough, but that is exclusive to one VM (on a consumer GTX 1080 anyway).

For basic use-cases, the default value should work fine - if don't need high-resolution output from your VM, increasing the VGA memory does not improve performance, just uses more memory.
 
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Are you referring to the "memory" parameters under "Hardware -> Display"? If so, that is not used for sharing GPU memory, it is just the buffer size of VRAM to allocate in main memory ("RAM") for the VM's emulated GPU.

You cannot "share" a GPU that easily, VMs will either use emulated graphics (which mostly run on the CPU) or you can assign an entire GPU via PCIe passthrough, but that is exclusive to one VM (on a consumer GTX 1080 anyway).

For basic use-cases, the default value should work fine - if don't need high-resolution output from your VM, increasing the VGA memory does not improve performance, just uses more memory.
Thanks for your reply!
Actually If I set GPU memory for example 512MB to the VM, at the inside of that VM If I render a video then only CPU works and GPU doesn't work. I'm also upgrade the amount of GPU memory to 8GB from VM's XML file but it had no effect!
Furthermore, when I install nox application on the Windows Server, there was an error which it says there is no any GPU on the system.
Could you please help me?
 
Thanks for your reply!
Actually If I set GPU memory for example 512MB to the VM, at the inside of that VM If I render a video then only CPU works and GPU doesn't work. I'm also upgrade the amount of GPU memory to 8GB from VM's XML file but it had no effect!
Furthermore, when I install nox application on the Windows Server, there was an error which it says there is no any GPU on the system.
Could you please help me?

You should be able to pass the entire card over to the windows VM pretty easily. You would need another video card for proxmox, or it would have to be headless.

https://pve.proxmox.com/wiki/PCI(e)_Passthrough
 
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You cannot efficiently share a consumer GPU with multiple users (i.e. VMs). For the use case you describe you need an SR-IOV (or similar) enabled graphics card, NVIDIA's GRID workstation cards for example. Or, add more GPUs - one per VM.
 
or, depeding on the use-case for the GPU you could use containers to access the card directly (hw-encoding/decoding for example)
 
You cannot efficiently share a consumer GPU with multiple users (i.e. VMs). For the use case you describe you need an SR-IOV (or similar) enabled graphics card, NVIDIA's GRID workstation cards for example. Or, add more GPUs - one per VM.
How about sharing something like a nvidia quadro? I know it is possible under VMWare ESXI, but I'd rather use KVM with Proxmox.
 
How about sharing something like a nvidia quadro? I know it is possible under VMWare ESXI, but I'd rather use KVM with Proxmox.
Yes, that's why I explicitly mentioned "consumer GPU". Anything that supports SR-IOV/mdev is supported on PVE as well, as long as you use the correct driver (i.e. NVIDIA GRID, which requires a license). This does not enable display output though, only GPU acceleration.

In the future, please don't reponse to a months old thread and just open a new one instead :)
 
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