On Sat, Feb 27, 2010 at 06:21:05PM +0100, Reimar D?ffinger wrote: > Yes of course, there will be no OpenGL support through Xen. > It's no surprise that OpenGL is slow in this case, I just > needed to figure out how to detect this case to fall back > to x11 then. Testing directory /sys/hypervisor ? I can also think of /sys/devices/xen(-backend)?. Not perfect for sure, but will be reliable in most situations I think.