Re: poor scrolling in qemu-kvm

[Ludovic Courtès]

Federico Beffa <address@hidden> skribis:

> Have someone found out the reason for this poor performance in
> qemu-kvm and how to fix it?

Yes, I eventually found out: by default, QEMU uses a Cirrus VGA graphics
adapter emulator, which is damn slow for this kind of framebuffer thing.

The right thing is to use ‘-vga std’, which uses a “standard VGA”
emulator, which doesn’t have this problem.

However, X will fail to start currently when using this.  The fix is to
use xf86-video-modesetting.  But this driver is not currently usable
because it requires a version of libdrm incompatible with that currently
used by xorg-server/MESA.

Long story short: we just need to update MESA to use the newer libdrm,
and we should be able to fix that.

Would you like to try?  :-)

Thanks,
Ludo’.