[vfio-users] threadripper slowness

[Roger Lawhorn]

Hello.
I am new to the list.
I have been doing gpu passthrough for almost 5 years now with a i7 
4940mx cpu on a msi gt70 laptop.

My new PC build is:
MSI x399 carbon pro motherboard : bios xxxxxx.1c0 : svm=enabled: 
iommu=enabled
Threadripper 2920 12 core
Radeon pro duo R9 Fury X
Nvidia 980 TI OC

I was unable to passthrough the nvidia card due to it not getting past 
the "Running option rom..." message when debugging.

The Radeon passed through with flying colors.

The issue:
I used the radeon to run triple A games in linux using steam for linux 
and proton. No problems.

In Windows 7 in qemu I have passed all 24 cpus to it.
They max out to 80% while playing the same triple A games and the games lag.
I have never had this issue before.

Admittedly I am using the same script I used on the i7 to get going.
I had to remove threads from the -smp switch and use cores only.

I also removed the kvm=off which is used for nvidia cards.

I am looking for links to articles or direct info on what to do to 
optimize the cpus.
When not lagging the radeon performs extremely well.

I am concerned that perhaps kvm is not being used.


Thanks