I’ve been using VBox virtual machines for many years to e.g. watch Youtube, listen to streams etc. and surf the internet normally. At every VM start the home directory is deleted, no long term cookies or so possible, other network cards are easily assignable…
I have now been trying KVM with Qemu for the last month. Set up with the Virt-Manager (link below). The automatic resolution adjustment works. (3D applications also works reasonably, which is much better than VBox). The VMs also start up faster with KVM.
But VMs with Virtualbox run fluffier and more performant as a desktop replacement. The VM machine is an Ubuntu 20.4VM with LXQT and Firefox. With Virtualbox I can limit the machine to one core with 80% speed and a Youtube video with 720p runs smoothly with 4GB memory. With KVM it only works with two cores and not full screen. It is the desktop in the VM generally not so smooth.
I’m VBox guy. I tried KVM once. It worked, but I prefer VBox because it’s easier to setup and, at the time I tried KVM, VBox performed better. I only use to run some windows applications, and it works very well for that purpose.
I’ve used VBox in the past, as well as Parallels Desktop on the Mac or VMware on Windows. VBox worked but was slow. I was able to run Windows or Linux VMs on all of these systems.
Now that I’m on Manjaro Linux as a host, I tried KVM/libvirt. I run a Win10 VM, plus one virtualized macOS. I found KVM to be the hardest to set up, but once you’ve got the hang of it, it’s super-fast. In particular, Win10 has decent Virtio driver support and runs quite smoothly. macOS is different, the user interface is very slow since there are no Virtio drivers available for that (there are for storage and networking, though). But it gets the job done.
With the Win10 guest I have dynamic screen resizing, shared clipboard and drag-and-drop file sharing. That all depends on the spice guest tools, which are unavailable on macOS. Other Linux guests might be fine, but I haven’t tried.
I had no problems with Windows in KVM either. Maybe I have to test KVM with Linux guests again. At the beginning of the year, desktop performance (watching Youtube, surfing the web) was even worse than with Virtual Box. Dynamic resolution also worked fine in KVM.
Reason I switched to virt-manager from virtualbox is because keyboard shortcuts in virtualbox guest don’t work with a wayland host. This doesn’t happen on virt-manager/kvm.
From my personal experience, generally speaking, qemu/kvm lacks 3d acceleration in windows guest, but in fact virtualbox’s 3d acceleration is not enough for you to play games smoothly, I now use pci passthrough to play games.
I used to run virtualbox and it was/is excellent, however I could not get myself to like the interface.
Using the virt-manager and the command line tools feels smoother/more powerfull/faster in getting things done for me. Big plus is the virt-manager gui conforms to the rest of the gui style. So for me this is mostly about style / way of working.
