I don’t see any performance differences with the vgpu actually. I have more performance bottlenecks with the CPU, and my RAM isn’t the fastest, so I think I’m more CPU limited. Benchmarks I have run that are GPU focused seem to show little to no difference from what the physical card would do.
I’ve always found the documentation around virtio-GPU and virtgl very lacking, and have never gotten them working. Would love to get pointers if anyone has a good source.