Fading effect slow with KMS in maverick

[Eugene Crosser]

Binary package hint: xserver-xorg-video-ati

On maverick with KMS enabled, programs that use video "fading" effect are unusably slow, screen updates "freeze" for seconds with X server using 100% CPU. Easy way to demonstrate it is to view this slideshow with Firefox:

http://www.electricprism.com/aeron/slideshow/example1.html

The problem is also apparent with other programs like F-Spot's slideshow, and is observable on different hardware with different models of Radeon adapters.

The effect disappears if you disable KMS (by adding "radeon.modeset=0" to the kernel command line).

Reported to xorg team https://bugs.freedesktop.org/show_bug.cgi?id=30872 and it turns out that the problem is fixed in newer versions of the driver. It does happen when running default 1:6.13.1-1ubuntu5 version but does not happen with the version from xorg-edgers PPA 1:6.13.99+git20101012.0d1f9fd0-0ubuntu0sarvatt.

[Jools Wills (jools)]

Can confirm this. I was also having this issue on lucid though too I'm sure, and it also affecting scrolling. disabling KMS solves it here - many thanks. Hopefully a new version of the driver can be rolled out on ubunut.

[Timo Aaltonen (tjaalton)]

fixed in natty ati version, as mentioned on the upstream bug.