[ovirt-users] 100% memory usage on desktop environments

[Nicolás]

Hi,

Probably not an oVirt issue, but maybe someone can help. I've deployed a 
pretty basic VM (ubuntu 14.04 server, 4GB RAM, 4 CPUs, 15GB storage). 
Each time I install an additional desktop environment (Gnome, KDE, 
whatever...), CPU usage rises to 100% all time to the extreme that 
interacting with the machine becomes impossible (maybe a mouse movement 
is propagated 3 minutes later or so...).

To debug this, I installed LXDE, which is a lightweight desktop 
environment based on Xorg. I could see there is an Xorg process 
consuming one of the CPUs and the machine stops responding as far as the 
desktop environment goes. I have not changed anything in the 
configuration file.

I could also see this only happens when QXL is chosen as the display 
driver. When CIRRUS is chosen, everything works smoothly and CPU is 
~100% idle. The downside is that we want to use SPICE and CIRRUS won't 
allow it.

Why does this happen? Is this an OS-side driver issue? Any hint how can 
it be fixed?

Thanks.

Nicolás