Bug 152661

Summary:	KDE4 somehow disables DRI
Product:	[I don't know] kde	Reporter:	Jörg Hermsdorf <yojoe>
Component:	general	Assignee:	kdelibs bugs <kdelibs-bugs>
Status:	RESOLVED WORKSFORME
Severity:	normal	CC:	adaptee, cyberbeat, l.lunak
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:

Description Jörg Hermsdorf 2007-11-21 17:21:42 UTC

Version:            (using KDE KDE 3.96.0)
Installed from:    SuSE RPMs

I have a Lenovo ThinkPad T60p with a ATI FireGL v5250 (M66) video device. Im using the fglrx driver version 8.40.4 on openSUSE 10.3 (x86_64). 
I installed the KDE4 RC1 packages from the openSUSE Buildservice.

When I start a KDE4 session, the UI is very slow. One thing I noticed is, that DRI is not available in the X-Session I run KDE4 in.

# glxinfo
name of display: :0.0
display: :0  screen: 0
direct rendering: No

The strange thing is, that when I logout of the KDE4 session and use the same user to start a KDE3 session, DRI is available.

Desktop Effects (compositing) are disabled in my KDE4 setup. I also looked through /var/log/Xorg.0.log, but there are no error messages indicating a problem with DRI. Actually, there are only log messages saying that DRI was successfully initialized.

So something in the KDE4 startup sequence must disable DRI for the X-Session. I don't know if the missing DRI in the KDE4 session is the reason why the UI is so slow. If I drop the fglrx driver and use the free radeonhd driver, which does not support any 2D or 3D acceleration yet, the KDE4 UI is much faster. So it's definitely a problem with the fglrx driver. The question is, is this a bug in the fglrx driver, which is only triggered by KDE4, or does some KDE4 component (e.g. kwin) messes something up.

Comment 1 Lubos Lunak 2007-11-21 18:41:28 UTC

I don't think any application even can disable DRI, it should be only issue of X or the driver. You can try killing plasma or using another window manager instead of kwin (e.g. 'metacity --replace').

Comment 2 Erik Hensema 2007-11-21 21:13:49 UTC

Confirmed on opensuse 10.3; kde4rc1; nvidea graphics driver.

Comment 3 Erik Hensema 2007-11-21 21:25:05 UTC

hmmmm, not confirmed. I don't have DRI in kde3 either.

Fact is, kde4 is dog slow while kde3 is snappy.

Comment 4 Severin Stampler 2007-11-28 14:12:25 UTC

I realize the same behaviour on openSuse 10.3 with the nvidia driver.
When I start kwin 4 in a kde3 session (by calling /usr/bin/kwin --replace) the desktop effects work but DRI is still enabled. Only when I start the kde4 session from kdm DRI is disabled.

Comment 5 copong 2008-01-15 18:51:01 UTC

Same on Kubuntu Gutsy.

Comment 6 H.H. 2008-08-22 21:45:14 UTC

I can confirm this for opensuse-11 with kde-4.1.62

Comment 7 Jekyll Wu 2011-09-24 04:21:03 UTC

(In reply to comment #6)
> I can confirm this for opensuse-11 with kde-4.1.62

Is this still a problem in recent version of KDE4 ?