Bug 30872

Summary: With KMS, fading effect is unusably slow (recent regression)
Product: xorg Reporter: Eugene Crosser <crosser>
Component: Driver/RadeonAssignee: xf86-video-ati maintainers <xorg-driver-ati>
Status: RESOLVED NOTABUG QA Contact: Xorg Project Team <xorg-team>
Severity: normal    
Priority: medium    
Version: 7.5 (2009.10)   
Hardware: All   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:
Attachments:
Description Flags
Xorg logfile
none
Xorg.log from Compaq 8510p running maverick from "live USB"
none
dmesg from Compaq 8510p none

Description Eugene Crosser 2010-10-14 08:23:39 UTC 
Some time late in Ubuntu Maverick 'alpha' period, visual effects that involve "fading" became unusably slow. The following javascript web slideshow, when viewed with Firefox, makes this effect very obvious:

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

but it is also apparent with e.g. F-Spot slideshow.

Disabling KMS by adding "radeon.modeset=0" to the kernel command line makes the problem go away.

The current version of X server on which I can reproduce the problem is 1:7.5+6ubuntu3. I observed the effect on three different machines with different Radeon models.

It looks somewhat similar to the bug #23513, but in my case, 3D performance is unaffected.

I can provide more information on request, though in fact I think that anyone can reproduce it at will; I see it when I boot from "live USB" containing Maverick.

Eugene
Comment 1 Alex Deucher 2010-10-14 08:35:22 UTC 
That page seems to work fine here.  What hardware are you using?  Can you attach your xorg log and dmesg output?  Any chance you can narrow down when this started or what update caused it?
Comment 2 Felix Blanke 2010-10-14 08:42:45 UTC 
Created attachment 39445 [details]
Xorg logfile
Comment 3 Felix Blanke 2010-10-14 08:43:13 UTC 
I can confirm that behaviour.

It also happens at me, but only with firefox. Opera works fine.

xorg-server: 1.9.0-r2
radeon: git @evergreen-accel branch
kernel: drm26 git kernel
hardware: Radeon HD 5750
Comment 4 Alex Deucher 2010-10-14 08:56:12 UTC 
(In reply to comment #3)
> I can confirm that behaviour.
> 
> It also happens at me, but only with firefox. Opera works fine.
> 
> xorg-server: 1.9.0-r2
> radeon: git @evergreen-accel branch
> kernel: drm26 git kernel
> hardware: Radeon HD 5750

Are you on ubuntu as well?  Also, evergreen_accel has been merged to master.  Does master work any better?
Comment 5 Felix Blanke 2010-10-14 11:40:31 UTC 
Oh, I didn't knew that. Is there a place where such things are annouced? Thats why there were no updates at the evergreen_accel branch :D

I'm not on ubuntu, I'm using gentoo. I'll test the master branch when I'm back at my linux later this evening.
Comment 6 Eugene Crosser 2010-10-14 12:35:48 UTC 
Created attachment 39452 [details]
Xorg.log from Compaq 8510p running maverick from "live USB"

As requested, I am attaching Xorg.log. This is just one case, I observe the same behavior on RS690 and on M56GL.
Comment 7 Eugene Crosser 2010-10-14 12:45:34 UTC 
Created attachment 39453 [details]
dmesg from Compaq 8510p

Also including `dmesg` output as requested.
Sorry I cannot give the exact point when the problem appeared: it is easy to not notice until you try to watch a slideshow.
Comment 8 Felix Blanke 2010-10-14 12:57:35 UTC 
Ok, it doesn't happen at me with the master branch. Sorry for that.
Comment 9 Alex Deucher 2010-10-14 13:10:34 UTC 
Eugene, can you try git master of xf86-video-ati?  Does that help?  Next could you try previous xf86-video-ati releases (6.13.0, 6.13.1, 6.13.2) and see where the problem started?
Comment 10 Eugene Crosser 2010-10-14 13:18:42 UTC 
Alex,
can I use some binary build(s) for this test? I remeber building from the source is not quick and I am somewhat time-constrained at the moment. (Please forgive me, it was not a good thing to say to the developers, and I really appreciate *your* time and effort, but...)
Comment 11 Eugene Crosser 2010-10-14 14:08:19 UTC 
I figured that I could first try prebuild packages from ubuntu edgers-ppa, and lo and behold! running 1:6.13.99+git20101012.0d1f9fd0-0ubuntu0sarvatt with KMS enabled the problem is gone!

So, sorry for bothering you, I will now go report on launchpad as it is apparently ubuntu-specific.

Eugene
Comment 12 Felix Blanke 2010-10-14 16:04:31 UTC 
Problem due old  driver Version!
Comment 13 Eugene Crosser 2010-10-15 01:23:19 UTC 
Reported to Ubuntu as https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/660999

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.