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Poor Performance on GVT-d

Hi everyone

First of all, I apologize to be that guy that creates an account just to ask a single question.

I’ve been trying to run looking glass for a couple weeks now, and (apparently) I’ve successfully passed through my integrated graphics (630 shows up on guest), but I’ve been stuck on 30fps/ups. If I set fps min to 144, LG shows 150+ fps, but UPS remains the same.

My question is - is GVT-d THAT slow? Shouldn’t I be getting better FPS/UPS when using 800x600? It’s not like I was running The Witcher maxed out, I was dragging an explorer window around and getting 30fps.

Things I’ve already tried:

  1. Reducing resolution to 800x600 (I’m using 1600x900)
  2. Using a different OS (tried win7, 8, 8.1, 10)
  3. Enabling hugepages (it fails, for some reason)
  4. Using b2, b3 and bleeding-edge hosts/clients

Setup:
8700k, 32gb, 1080ti, and a bunch of hdd/ssd/nvme. Guest and host are in the same nvme

To test the UPS, I usually drag windows around and/or play 120hz videos.

Edit: my xml

<domain type="kvm">
  <name>win10</name>
  <uuid>f3a4dd3c-0ba1-492d-aa1a-05c5b8c5312e</uuid>
  <metadata>
    <libosinfo:libosinfo xmlns:libosinfo="link">
      <libosinfo:os id="link"/>
    </libosinfo:libosinfo>
  </metadata>
  <memory unit="KiB">16777216</memory>
  <currentMemory unit="KiB">16777216</currentMemory>
  <vcpu placement="static">8</vcpu>
  <cputune>
    <vcpupin vcpu="0" cpuset="2"/>
    <vcpupin vcpu="1" cpuset="8"/>
    <vcpupin vcpu="2" cpuset="3"/>
    <vcpupin vcpu="3" cpuset="9"/>
    <vcpupin vcpu="4" cpuset="4"/>
    <vcpupin vcpu="5" cpuset="10"/>
    <vcpupin vcpu="6" cpuset="5"/>
    <vcpupin vcpu="7" cpuset="11"/>
    <emulatorpin cpuset="0-1,6-7"/>
  </cputune>
  <os>
    <type arch="x86_64" machine="pc-q35-5.2">hvm</type>
    <boot dev="hd"/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <hyperv>
      <relaxed state="on"/>
      <vapic state="on"/>
      <spinlocks state="on" retries="8191"/>
      <vendor_id state="on" value="whatever"/>
    </hyperv>
    <kvm>
      <hidden state="on"/>
    </kvm>
  </features>
  <cpu mode="host-passthrough" check="none" migratable="on">
    <topology sockets="1" dies="1" cores="4" 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="cdrom">
      <driver name="qemu" type="raw"/>
      <source file="/home/rvale/Downloads/windows_10.iso"/>
      <target dev="sdb" bus="sata"/>
      <readonly/>
      <address type="drive" controller="0" bus="0" target="0" unit="1"/>
    </disk>
    <disk type="file" device="disk">
      <driver name="qemu" type="qcow2"/>
      <source file="/home/rvale/VirtualMachines/win10.qcow2"/>
      <target dev="sdc" bus="sata"/>
      <address type="drive" controller="0" bus="0" target="0" unit="2"/>
    </disk>
    <disk type="file" device="disk">
      <driver name="qemu" type="qcow2"/>
      <source file="/var/lib/libvirt/images/win10.qcow2"/>
      <target dev="sdd" bus="sata"/>
      <address type="drive" controller="0" bus="0" target="0" unit="3"/>
    </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="0x16"/>
      <address type="pci" domain="0x0000" bus="0x00" slot="0x02" function="0x6"/>
    </controller>
    <controller type="pci" index="8" model="pcie-to-pci-bridge">
      <model name="pcie-pci-bridge"/>
      <address type="pci" domain="0x0000" bus="0x06" slot="0x00" function="0x0"/>
    </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:ec:71:34"/>
      <source network="default"/>
      <model type="e1000e"/>
      <address type="pci" domain="0x0000" bus="0x01" slot="0x00" function="0x0"/>
    </interface>
    <serial type="pty">
      <target type="isa-serial" port="0">
        <model name="isa-serial"/>
      </target>
    </serial>
    <console type="pty">
      <target type="serial" port="0"/>
    </console>
    <channel type="spicevmc">
      <target type="virtio" name="com.redhat.spice.0"/>
      <address type="virtio-serial" controller="0" bus="0" port="1"/>
    </channel>
    <input type="tablet" bus="usb">
      <address type="usb" bus="0" port="1"/>
    </input>
    <input type="mouse" bus="ps2"/>
    <input type="keyboard" bus="ps2"/>
    <graphics type="spice" autoport="yes">
      <listen type="address"/>
      <image compression="off"/>
    </graphics>
    <sound model="ich9">
      <address type="pci" domain="0x0000" bus="0x00" slot="0x1b" function="0x0"/>
    </sound>
    <video>
      <model type="none"/>
    </video>
    <hostdev mode="subsystem" type="pci" managed="yes">
      <source>
        <address domain="0x0000" bus="0x00" slot="0x02" function="0x0"/>
      </source>
      <address type="pci" domain="0x0000" bus="0x04" slot="0x00" function="0x0"/>
    </hostdev>
    <redirdev bus="usb" type="spicevmc">
      <address type="usb" bus="0" port="2"/>
    </redirdev>
    <memballoon model="virtio">
      <address type="pci" domain="0x0000" bus="0x05" slot="0x00" function="0x0"/>
    </memballoon>
    <shmem name="looking-glass">
      <model type="ivshmem-plain"/>
      <size unit="M">64</size>
      <address type="pci" domain="0x0000" bus="0x08" slot="0x01" function="0x0"/>
    </shmem>
  </devices>
</domain>

IGPs are bandwidth limited as they share system RAM for VGA RAM, usually people pass through a dGPU. I think this is the first time I have seen someone trying to pass through an iGPU for the guest with LG.

Yeah I’d suggest you reverse things. Use the integrated graphics for the host and pass thru the 1080 to your VM. For me this works OK (fast ram helps) but I’m stuck with iGPU on the host because I can’t spare the PCIe resources for a 2nd video card on my current motherboard. It’s enough to support [email protected] which is all my monitor is good for.

Yeah, looks like I’m gonna have to buy another gpu to make this work. I have 2 displays connected to my gpu, and my mobo offers only a single hdmi port. Thank you for your time, guys