Type 1 Hypervisor on the desktop

I have a powerful home PC, and I've used VirtualBox to run Linux distros in Windows (and vice versa).

I'm interested in trying out a lightweight type 1 hypervisor to run all my operating systems (Windows 7, Debian, Arch) and was looking for suggestions of which to pick and how to implement this.

From what I gather, a type 1 hypervisor is a lightweight OS which simply provides VM management functionality.

Will I get reasonable performance under each guest OS? Can all the guest OSs have access to a shared data drive, or is is best to have a storage server in another guest OS and mount it over the virtual network?

What about gaming, is this feasible, or will I realistically need to run Win7 on bare metal?

I'd appreciate any input.

It would seem that good progress has been made in VGA passthrough, in the last 18 months, so there is a chance such setup might work today. The requirement here is that all of the hardware elements (CPU, motherboard, GPU) do support IOMMU, that is either Intel VT-d or AMD-Vi (these are not the same as VT-x or AMD-V).

I am about to try something similar; my plan A (there might be B, C ... if A fails) is to try KVM with very recent (stable) versions of kernel, libvirt and qemu. I will most likely start with either of distributions Arch, Fedora or Proxmox (ie. Debian optimized for KVM). I might even try doing the same thing with various distros to compare the process and effect.

If you are still interested in answer, I found this useful guide which is being continuously updated and kept up-to-date (as of today - see date of my answer below). I plan to base my work on this guide KVM VGA-Passthrough on ArchLinux forums

KVM is not the only option, there is also strong support in Xen community for VGA passthrough, it is also supported under new versions of EXSi. If I need plan B or C, these will be my choices.

First, the distinction between "Type 1" and "Type 2" hypervisors is rather blurred these days. It's certainly a bit different than the original 1973 definition. After all, many of the hypervisors commonly referred to as "Type 1" are not actually bare metal hypervisors, but rely on a host OS to some extent.

These days many people say "Type 1" when they mean "server" and "Type 2" when they mean "workstation." These are not the original definitions, so paying attention to this artificial distinction will be quite confusing.

It's more useful to determine whether the hypervisor can accomplish what you want to do.

With that out of the way:

All of the popular hypervisors provide reasonable near-native performance once guest tools/paravirtualized drivers are installed. The main exception to this is 3D graphics, which will typically run poorly compared to native performance even with drivers.

While it's possible (with a processor that supports VT-d) to reserve a host video card for the exclusive use of a virtual machine, this is not well supported in many hypervisors as they concentrated their development of this feature on giving VMs raw access to network cards.

If you're a gamer, you should consider running a desktop virtualization solution such as VMware Workstation or VirtualBox so that you can game on the host OS and have the highest possible performance from your games.

If you want to share data between your guest OSes, you can either create a VM specifically for this purpose, or use features of the various virtualization solutions to provide access to folders on the host's hard drive (e.g. VirtualBox and VMware Workstation provide "shared folders" which maps a directory on the host hard drive to a virtual hard drive or virtual network share in the guest).