I haven’t tested synthetic benchmarks but games only, will give it a try later today.
For older games it works pretty fine (with some fps lows but very playable) like battlefield 4. But for newer stuff like Lies of P, I can’t get past 60FPS even in low settings, the same for Elden Ring, low 2 FPS and average 40 with max settings and no RT.
I have pinned 16 of my CPUs (same L3 cache group) and the only thing I have to hide virtualization is this:
I haven’t digged into Windows treating it as VM but will give it a try, as the only thing I am doing is to disable kvm steate with:
<kvm>
<hidden state="on"/>
</kvm>
EDIT: Your suggestion was right! It was VBS…, I added the following lines and now it works so much better even in x4!. Before my GPU was about 60-70% utilization with CPU at 30-50% so CPU bottleneck was not a problem neither was storage (NVMe passthrough). Now I got steady 60FPS in Elden Ring at 3840x1600 Max Settings + Max RT (some drops when loading scenes but lowering RT fixes it). Also +144 FPS in Lies of P, before I was getting nowhere close to that.
<hyperv mode="passthrough">
<relaxed state="on"/>
<vapic state="on"/>
<spinlocks state="on" retries="8191"/>
</hyperv>
<kvm>
<hidden state="on"/>
</kvm>
<vmport state="off"/>
<cpu mode="host-passthrough" check="full" migratable="on">
<topology sockets="1" dies="1" cores="8" threads="2"/>
<cache mode="passthrough"/>
<feature policy="require" name="topoext"/>
<feature policy="disable" name="svm"/>
<feature policy="require" name="hypervisor"/>
I am happy to share any more of my experience with the 5080 Passthrough.
Current Build is:
Ubuntu 24.04 Kernel 6.8.0-52, Secure Boot Enabled
Looking-Glass B7
Motherboard - TRX50 Sage WiFi
CPU: AMD Threadripper 7980X
Host GPU: NVIDIA RTX A2000 12GB (2nd slot) - NVIDIA Open Drivers 570.133.07
Guest GPU: NVIDIA RTX 5080 - Windows Drivers 576.02
BIOS Settings:
CSM Enabled
Resizable BAR Disabled
SR-IOV Disabled
SVM Enabled
Relevant GRUB Lines:
GRUB_CMDLINE_LINUX_DEFAULT="pci=realloc=off amd_iommu=on iommu=pt vfio-pci.ids=10de:2c02,10de:22e9 vfio_iommu_type1.allow_unsafe_interrupts=1 "
/etc/modprobe.d/vfio.conf
softdep nvidia pre: vfio-pci
softdep nouveau pre: vfio-cpi
options vfio-pci ids=10de:2c02,10de:22e9
Relevant Virsh config:
<features>
<acpi/>
<apic/>
<hyperv mode="passthrough">
<relaxed state="on"/>
<vapic state="on"/>
<spinlocks state="on" retries="8191"/>
</hyperv>
<kvm>
<hidden state="on"/>
</kvm>
<vmport state="off"/>
<smm state="on"/>
</features>
<cpu mode="host-passthrough" check="full" migratable="on">
<topology sockets="1" dies="1" cores="8" threads="2"/>
<cache mode="passthrough"/>
<feature policy="require" name="topoext"/>
<feature policy="disable" name="svm"/>
<feature policy="require" name="hypervisor"/>
</cpu>
Default Settings for GPU passthrough (ROM BAR Enabled)
<hostdev mode="subsystem" type="pci" managed="yes">
<driver name="vfio"/>
<source>
<address domain="0x0000" bus="0x42" slot="0x00" function="0x0"/>
</source>
<alias name="hostdev0"/>
<address type="pci" domain="0x0000" bus="0x05" slot="0x00" function="0x0"/>
</hostdev>
Thanks a lot!
