Different performance with different user accounts?

[Michel Dänzer]

On Thu, 2009-12-10 at 00:45 +0100, Ancoron Luciferis wrote: 
> 
> I have a machine with two user accounts under Kubuntu 9.10 and the
> performance difference I am experiencing is measurable. The first user
> account (set up during installation time) works good. Glxgears is around
> 4000 FPS, video playback is fine, compositing is fine (especially the
> desktop cube is fast as hell and really smooth).
> 
> On the other hand there is a second user account (this one is not in the
> admin group but basic setup is the same). In that user account I get
> only around 2700 FPS, compositing works fine (the cube is still that
> fast) but moving windows around is dead slow and video playback is NOT
> "tear-free". The rather strange thing is that it doesn't depend on video
> source frame size or codec or scaled frame size, the playback is just
> dropping frames especially when there is a lot of movement.
> 
> Turning off the compositing results in a fast user experience but since
> it is fast with compositing for the first user I expected it to be the
> same for the second one.
> 
> CPU usage is not the problem as the quad-core machine is idling around
> between 70% and 90% although Xorg is between 30 and 50% and mplayer
> between 1% and 26% (peeks up to 47%) when watching a movie.
> 
> System:
> - - AMD Athlon II X4 620
> - - 4GB RAM
> - - Radeon X1950XTX
> - - Dell 3007WFP-HC 30" @ 2560x1600
> 
> This doesn't make sense for me at all.
> 
> Can someone shed some light on this?

Have you tried comparing e.g. the glxinfo output between the two
accounts?


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer