I have been running my main workstation as a Linux VM with GPU passthrough running on ProxMox. The idea is to have my home network, workstation, learning, and work environments all on one system. For work, I do need access to Windows and macOS, and run Windows with and without GPU passthrough and macOS with GPU passthrough when needed. I have two x16 GPUs and a PCI VGA card for the ProxMox host.
My system consists of an AMD FX-8350 with 32 GB of RAM on an ASRock FX-990 Extreme 4.
Running Unigine Heaven on Windows I get 111 FPS and a score of 2796 with everything set to Extreme at 1080p. I get similar results regardless of the test being done in DirectX or OpenGL.
Running Unigine Heaven on Linux I get 77 FPS and a score of 1938 with everything set to Extreme at 1080p.
For these tests I used a 1080 GTX Ti. I ran these tests one at a time with 8GB and 8 cores going to the VM. The only VM I had running other than the workstation was pfSense.
To troubleshoot, I have tried different distros and through the years have had different GPUs installed. My score is always significantly lower in Linux.
The virtual hardware, CPU, RAM, UEFI, disk controller, disk storage, and disk caching settings are identical between the Linux and Windows guests.
I know most people are running Windows for gaming, and my scores in Windows seem like bare metal performance. Does anyone have experience running Linux as a VM with GPU Passthrough? Has anybody gotten equal or similar performance in Linux and Windows?