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KVM/qemu With Virtio drivers... Whats the #1 way to get native levels of responsiveness?

I have an old server mobo (Opteron 6284SE x 2)

I’m using linux as a host with KVM/qemu With Virtio drivers and WIn 10 as guest…

The performance is decent… but how can I improve things to to get native levels of responsiveness? Would upgrading my GPU help? I have an AMD wx 2100, 1 monitor at 1440P 60hz…

And this is all NON gaming btw. I am after a native desktop feel. So, if I were recording a screen cast, it would appear native and fast. Right now it is lagging enough to notice.

Make sure Windows 10 has access to more then one core. By default, a lot of tools will have one socket per core for kvm. Windows 10 can only use one(home) or two(pro or better) sockets. So make sure that windows can use enough cores.

I also would suggest running it off of a SSD. Windows is slow enough on bare metal with a HDD, and gets much worse when running from an image on a HDD.

I also assume you are giving it at least 6gb ram?

After those, it is probably the emulated video card that is slowing things down. You could try switching it out for a different type, but I don’t think it will fix it. You would have to passthrough a GPU and use looking-glass to get good graphics performance.

I have it set as 1 socket, 8 cores, 8 threads. It’s running off an NVME, also 8gb of memory

Graphics is the area to look at then.

I just loaded my Win 10 vmware workstation VM and it is seriously far more responsive.

how are you controlling the VM? i feel Spice or VNC may be at fault here.

SPICE/qemu

Weird. I fixed it. The virtio drivers in KVM had switched back to QXL

NM again, it was supposed to be QXL, the driver in windows had disappeared!

Double check that in the docs or inside your VM. Because I think the threads setting should be 2 in the libvirtd config.

@TheCakeIsNaOH While I agree with your statement to Amdfan2929 about passing through a graphics card to get more performance, as far as I know, looking glass is only used to get around the requirement of needing a separate monitor for your guest system.

I agree, and I could have worded it better. I was assuming that @amdfan2929 wanted a similar experience to default kvm/qemu with a OS inside a window.

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It seems like vmware workstation has better performance. I used cinebench in both and got about 1,100 in vmware and about 1,100 in kvm, but the actual dragging of windows is MUCH smoother in vmware.