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Looking Glass: Run a Windows VM on Linux in a window with native performance

looking-glass.io

31–40 of 312 posts

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#31
post #8

The problem is that you have to have a monitor plugged in the windows card otherwise it goes all wonky. At that point you could just use a KVM....

KVM switches are often slow and/or buggy and/or expensive. Plus, looking glass is more flexible since you can display both OSs at the same time.

As a sibling comment stated, you can get a dummy monitor plug on Amazon for like $5 which fools your GPU into thinking there's a monitor attached.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#33
post #22

Earlier quoted context omitted.

It's too limiting, if you're doing the whole VFIO thing in the first place you don't really want to limit yourself to just Windows in a specific configuration. You want to have an ability to run any OS you can and pass your hardware to it. I wouldn't recommend VFIO just for gaming, there are better options.

What exactly is limiting about it? I use it on a daily basis in order to flip between high performance Linux and high performance Windows instantly with the flick of a hotkey. I use it for gaming, software dev, and just in general it's nice to be able to switch OSs for any reason instantly. What better options are there?

Flipping between OS wasn't how I used VFIO. I had two different OS running on two monitors and both having access to underlying Linux shell.

Basically it's not worth setting up VFIO just for gaming, but if you already on top of that mountain, then use whatever. I stopped using VFIO a while back and just bought a laptop that runs Linux without any issues.

I don't really have time for games now, but if I wanted to play I would probably wait until next LTSC and install it + latest WSL on my PC. Or would buy a console, maybe that Steam Deck.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#34
post #23

What does this do that regular KVM + Qemu does not?

It provides bare metal access to the entire hardware stack. So for instance you could run Linux via your integrated GPU (the one on many consumer CPUs) while passing through your dedicated GPU to the Windows VM. This is how I "gamed on Linux" from 2018~2020 when I ran Ubuntu as my primary OS. It's incredibly finicky to set up (shocker, I know!) but if you're able to get it working it's truly amazing. Talking like 1%…

Just use Proton. Install games from Steam directly.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#35
post #23

What does this do that regular KVM + Qemu does not?

It's in the title of the post. You can run your VM in a regular window but at high performance (think gaming and professional stuff that's GPU heavy). You otherwise can't do this without a hardware KVM switch (or tossing the VM and just dual booting). Hardware KVM switches are expensive and often don't work very well. And still, with a KVM switch it wouldn't be running inside a window. It would consume your whole scr…

Is it possible to run Windows in KVM, without the extra GPU or KVM switch, but with degraded performance? Not for gaming, but for example for Office use?

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#36

Earlier quoted context omitted.

It provides bare metal access to the entire hardware stack. So for instance you could run Linux via your integrated GPU (the one on many consumer CPUs) while passing through your dedicated GPU to the Windows VM. This is how I "gamed on Linux" from 2018~2020 when I ran Ubuntu as my primary OS. It's incredibly finicky to set up (shocker, I know!) but if you're able to get it working it's truly amazing. Talking like 1%…

Just use Proton. Install games from Steam directly.

Atleast right now, most anticheat software aren't available for Linux, You need a Windows kernel for them to run.

This can however change as Steam plans to use SteamOS (based on Arch) as their primary OS on the SteamDeck.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#37
post #36

Earlier quoted context omitted.

Just use Proton. Install games from Steam directly.

Atleast right now, most anticheat software aren't available for Linux, You need a Windows kernel for them to run. This can however change as Steam plans to use SteamOS (based on Arch) as their primary OS on the SteamDeck.

And only a minority of games do require anticheat.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#38
post #8

The problem is that you have to have a monitor plugged in the windows card otherwise it goes all wonky. At that point you could just use a KVM....

Not only are there dummy plugs, but some cards (e.g., Quadro) let you spoof the EDID without one at all.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#39
post #35

Earlier quoted context omitted.

It's in the title of the post. You can run your VM in a regular window but at high performance (think gaming and professional stuff that's GPU heavy). You otherwise can't do this without a hardware KVM switch (or tossing the VM and just dual booting). Hardware KVM switches are expensive and often don't work very well. And still, with a KVM switch it wouldn't be running inside a window. It would consume your whole scr…

Is it possible to run Windows in KVM, without the extra GPU or KVM switch, but with degraded performance? Not for gaming, but for example for Office use?

Yes, QXL can do that and has built-in support in e.g. virt-manager. It's not going to be fast, but it does work, and is how installation of Looking Glass can be bootstrapped without a physical monitor attached.

Re: Looking Glass: Run a Windows VM on Linux in a window with native performance

#40
The question everyone is wondering: is this ready for serious use for gaming and productivity (Eg, photoshop or game development)? Or is it very hard to get a smooth workflow going? If the workflow is not great, is there a clear path to solving that?
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