QXL is a long-established and old way to get reasonably good graphics
performance in QEMU, but what if that is not good enough? How do you
get better performance? In newer versions of QEMU, 2.6+, virtio-gpu
is a higher performance option available. Functionality is excellent
on Linux; however, Windows support is still sparsely documented and in
an unknown state. Nevertheless, even if you select virtio video on
a Windows VM and start it up, you’ll notice you get better 2D graphics
performance with the Windows generic drivers, at the expense of screen
tearing.
20200127/DuckDuckGo virtio 3d acceleration not supported
20200127/DuckDuckGo virt-viewer screen tearing
20200127/DuckDuckGo virtio display driver
20200127/DuckDuckGo kvm qxl versus virtio video
20200127/DuckDuckGo qxl or virtio video
20200127/https://wiki.archlinux.org/index.php/QEMU/Guest_graphics_acceleration