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Vfio passthrough vm stutter with nvidia drivers

Hi, I have been attempting to get GPU passthrough working and now I am on the final step of setting up the vm and I am getting problems.
My GPU gets passed through and I am able to see the windows vm through my other monitor. Without the nvidia drivers the whole vm runs smoothly, but as soon as I install the drivers I start getting stuttering and lag. Opening up a application causes stutter and lag, and moving my mouse does the same. However, when I open an application that is full screen (such as a game or steam big picture mode) the stutter and lag goes away. I am not too sure what is the problem. Also, while I am playing a game, 5 minutes in I get booted out, the monitor goes black but virt-manager shows that the vm is still running.

My spec
AMD Ryzen 3700x
Asrock x570 taichi
Rtx 2070 super (Guest)
gtx 650 (Host)

my xml configuration
>

  <name>win10</name>
  <uuid>5d19b030-f082-4c22-9ce8-b11b4086b5ef</uuid>
  <metadata>
    <libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0">
      <libosinfo:os id="http://microsoft.com/win/10"/>
    </libosinfo:libosinfo>
  </metadata>
  <memory unit="KiB">17408000</memory>
  <currentMemory unit="KiB">17408000</currentMemory>
  <vcpu placement="static">12</vcpu>
  <os>
    <type arch="x86_64" machine="pc-q35-4.0">hvm</type>
    <loader readonly="yes" type="pflash">/usr/share/ovmf/x64/OVMF_CODE.fd</loader>
    <nvram>/var/lib/libvirt/qemu/nvram/win10_VARS.fd</nvram>
  </os>
  <features>
    <acpi/>
    <apic/>
    <hyperv>
      <relaxed state="on"/>
      <vapic state="on"/>
      <spinlocks state="on" retries="8191"/>
      <vendor_id state="on" value="123456789"/>
    </hyperv>
    <kvm>
      <hidden state="on"/>
    </kvm>
    <vmport state="off"/>
  </features>
  <cpu mode="host-model" check="partial">
    <model fallback="allow"/>
    <topology sockets="1" cores="6" threads="2"/>
  </cpu>
  <clock offset="localtime">
    <timer name="rtc" tickpolicy="catchup"/>
    <timer name="pit" tickpolicy="delay"/>
    <timer name="hpet" present="no"/>
    <timer name="hypervclock" present="yes"/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>destroy</on_crash>
  <pm>
    <suspend-to-mem enabled="no"/>
    <suspend-to-disk enabled="no"/>
  </pm>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type="file" device="disk">
      <driver name="qemu" type="qcow2"/>
      <source file="/var/lib/libvirt/images/win10.qcow2"/>
      <target dev="vda" bus="virtio"/>
      <boot order="2"/>
      <address type="pci" domain="0x0000" bus="0x04" slot="0x00" function="0x0"/>
    </disk>
    <disk type="file" device="cdrom">
      <driver name="qemu" type="raw"/>
      <source file="/run/media/dilan/Windows/Win10_1903_V1_English_x64.iso"/>
      <target dev="sdb" bus="sata"/>
      <readonly/>
      <boot order="1"/>
      <address type="drive" controller="0" bus="0" target="0" unit="1"/>
    </disk>
    <disk type="file" device="cdrom">
      <driver name="qemu" type="raw"/>
      <source file="/run/media/dilan/Windows/test/virtio-win-0.1.141.iso"/>
      <target dev="sdc" bus="sata"/>
      <readonly/>
      <address type="drive" controller="0" bus="0" target="0" unit="2"/>
    </disk>
    <controller type="usb" index="0" model="qemu-xhci" ports="15">
      <address type="pci" domain="0x0000" bus="0x02" slot="0x00" function="0x0"/>
    </controller>
    <controller type="sata" index="0">
      <address type="pci" domain="0x0000" bus="0x00" slot="0x1f" function="0x2"/>
    </controller>
    <controller type="pci" index="0" model="pcie-root"/>
    <controller type="pci" index="1" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="1" port="0x10"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x0" multifunction="on"/>
    </controller>
    <controller type="pci" index="2" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="2" port="0x11"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x1"/>
    </controller>
    <controller type="pci" index="3" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="3" port="0x12"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x2"/>
    </controller>
    <controller type="pci" index="4" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="4" port="0x13"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x3"/>
    </controller>
    <controller type="pci" index="5" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="5" port="0x14"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x4"/>
    </controller>
    <controller type="pci" index="6" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="6" port="0x15"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x5"/>
    </controller>
    <controller type="pci" index="7" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="7" port="0x8"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x01" function="0x0" multifunction="on"/>
    </controller>
    <controller type="pci" index="8" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="8" port="0x9"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x01" function="0x1"/>
    </controller>
    <controller type="pci" index="9" model="pcie-root-port">
      <model name="pcie-root-port"/>
      <target chassis="9" port="0xa"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x01" function="0x2"/>
    </controller>
    <controller type="virtio-serial" index="0">
      <address type="pci" domain="0x0000" bus="0x03" slot="0x00" function="0x0"/>
    </controller>
    <interface type="network">
      <mac address="52:54:00:7d:6a:22"/>
      <source network="default"/>
      <model type="e1000e"/>
      <address type="pci" domain="0x0000" bus="0x01" slot="0x00" function="0x0"/>
    </interface>
    <input type="mouse" bus="ps2"/>
    <input type="keyboard" bus="ps2"/>
    <hostdev mode="subsystem" type="pci" managed="yes">
      <source>
        <address domain="0x0000" bus="0x0d" slot="0x00" function="0x3"/>
      </source>
      <address type="pci" domain="0x0000" bus="0x06" slot="0x00" function="0x0"/>
    </hostdev>
    <hostdev mode="subsystem" type="pci" managed="yes">
      <source>
        <address domain="0x0000" bus="0x0d" slot="0x00" function="0x1"/>
      </source>
      <address type="pci" domain="0x0000" bus="0x07" slot="0x00" function="0x0"/>
    </hostdev>
    <hostdev mode="subsystem" type="pci" managed="yes">
      <source>
        <address domain="0x0000" bus="0x0d" slot="0x00" function="0x2"/>
      </source>
      <address type="pci" domain="0x0000" bus="0x08" slot="0x00" function="0x0"/>
    </hostdev>
    <hostdev mode="subsystem" type="pci" managed="yes">
      <source>
        <address domain="0x0000" bus="0x0d" slot="0x00" function="0x0"/>
      </source>
      <address type="pci" domain="0x0000" bus="0x09" slot="0x00" function="0x0"/>
    </hostdev>
    <memballoon model="virtio">
      <address type="pci" domain="0x0000" bus="0x05" slot="0x00" function="0x0"/>
    </memballoon>
  </devices>
  <qemu:commandline>
    <qemu:arg value="-object"/>
    <qemu:arg value="input-linux,id=mouse1,evdev=/dev/input/by-id/usb-Razer_Razer_Mamba_Elite-event-mouse"/>
    <qemu:arg value="-object"/>
    <qemu:arg value="input-linux,id=kbd1,evdev=/dev/input/by-id/usb-Razer_Razer_BlackWidow_Chroma_V2-event-kbd,grab_all=on,repeat=on"/>
    <qemu:arg value="-cpu"/>
    <qemu:arg value="host,hv_time,kvm=off,hv_vendor_id=null"/>
  </qemu:commandline>
</domain>

any help will be much appreciated

UPDATE:
I installed windows 8.1 and the stuttering and lag is gone. This could be a problem with windows 10 1903. I will try an older version of windows 10.

did you ever figure out the issue?

I am having the same problem with a much different configuration.
Host is: 7960x, x299-A Prime, Windows 10 1809, 1080ti guest, RX570 host, Ubuntu 19.10…

I would recommend making your own thread on this issue.

There are people who are willing to help (myself included) if you include your XML and system configuration. Can’t really say anything until I see the XML though

This fixed the problem for me with a 1080ti on Windows 10 1903:
https://www.labsrc.com/unraid-nvidia-gpu-passthrough-fix-qemu/
MSI Enable on both video + audio component fixed it.
Got looking glass going too, just to solve the mouse speed issue while in game.

That didn’t help me. Msi was enabled by default.
What helped the most was running Windows in “ultimate performance power profile” . And disabling power states in bios. I seem to be cpu bound even though I game at 4k.
I have only a 6700k though. So maybe as he says there’s just stuttering in newer windows builds. I did have stuttering in many games when running natively. Some games run as well as native others run like a mess.