Arch Linux

Thisguy_

Member

Registered: 2012-12-03

Posts: 41

Virtualization under Arch via Qemu

I've been playing around with Virtualization recently, and in order to somewhat keep things nice and tidy, I think I have decided to virtualize an instance of Windows as opposed to actually installing it on my computer. In order to improve the efficiency of it and make it as close to the "real" deal as possible, I want to keep the X server as low-load as possible outside of the virtualization. I tried to simply execute qemu with lots of nice flags as my .xinitrc, but apparently Qemu doesn't really enjoy being alone in X and the X server shut down rather quickly. I already run openbox, which in my opinion is a borderline acceptable amount of resource usage to run behind Qemu, but of course I would like to optimize as much as possible. Furthermore, I'm not even sure this entire deal is worth it in the first place.

I'm starting Qemu as follows (and have yet to obtain a Windows iso to do more extensive testing with):

qemu-system-x86_64 -hda /mnt/diskname -soundhw hda -cdrom /path/to/iso -enable-kvm -vga std -m 3072 -boot order=c -daemonize

Where /mnt is /dev/sda4.

So to boil it all down, I've got 3 questions for you:

1. Is virtualizing Windows in Arch a more or less acceptable way to run your average video game on 4GB of RAM and an Intel i3 processor?
2. If this is no pointless endeavor, how can I improve the efficiency of the Virtual Machine?
3. Am I missing some kind of brilliant Qemu option which can address #2, and is KVM going to hinder instead of help with virtualizing Windows?

EDIT: To be positively clear, before it is asked: no, I do not intend to use an illegal copy of Windows.

Last edited by Thisguy_ (2013-04-25 15:48:40)

alphaniner

Member

From: Ancapistan

Registered: 2010-07-12

Posts: 2,810

Re: Virtualization under Arch via Qemu

1) Most likely, no. If you're trying to do anything that requires 3d acceleration, you're out of luck. It's not even necessarily a matter of performance. Last I tried, I was unable to even launch the Skyrim Creation Kit in a qemu/kvm VM.

2) Look into IOMMU, aka PCI Passthrough. See "Create a Gaming Virtual Machine" at overclock.net. However, this requires CPU and mobo support*. I know i3s do not support it, so this is more of a "plan for the future" suggestion.

3b) Qemu without KVM is emulation, not virtualization. And that pretty much means poorer performance.

* To see [Intel] CPU support go to Intel ARK Advanced Search and select 'Yes' for the option "Intel® Virtualization Technology for Directed I/O (VT-d)". Desktop (as opposed to server) mobo support is a relative crapshoot.

Last edited by alphaniner (2013-04-25 17:48:00)

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nbhs

Member

From: Montevideo, Uruguay

Registered: 2013-05-02

Posts: 402

Re: Virtualization under Arch via Qemu

What you need to do is passthrough your gpu to the windows VM, please see my post @nbhusain on http://www.overclock.net/t/1205216/guid … achine/600, i managed to passthrough a RADEON 6950 and a GEFORCE 470 gtx using arch,kernel 3.9, qemu-git from AUR, and a patched seabios, i also passed my sata controller with the windows drive connected to it (seabios boots from it), and my usb3 ports so performance is almost native.

Last edited by nbhs (2013-05-02 22:16:51)