Bug 282391

Summary:	Slow performance of Gl-based screensavers while using OpenGl compositing.
Product:	[Unmaintained] kscreensaver	Reporter:	godlike_devil
Component:	general	Assignee:	kscreensaver bugs tracking <kscreensaver-bugs-null>
Status:	RESOLVED INTENTIONAL
Severity:	wishlist	CC:	delleceste, martin.tlustos, mgraesslin
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Ubuntu
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	xorg.conf xorg.conf Xorg log file

Description godlike_devil 2011-09-20 10:14:01 UTC

Version:           unspecified (using KDE 4.7.0) 
OS:                Linux

I have payed attention that screensaver performance goes terrible slow if I set one of the GL-based savers.
It happens while the compositing is turned on/
When I'm turning off compositing or setting to disable it on full-screen the savers are running fast and clean w/o lagging.
I was thought it will be nice just to disable compositing for screensaver. I dont want to set "Disable effects for full screen" because it makes other application work glichy (e.g fullscreen vlc playback).



Reproducible: Always

Steps to Reproduce:
Turn compositing on.
set kscreensaver to Gl based one.

Actual Results:  
screensaver goes laggy.

Expected Results:  
disable compositing for screensaver only.

Comment 1 Martin Tlustos 2012-05-16 13:26:21 UTC

It might be because of your graphic card. I have an intel card that has exactly the same problem, but other cards don't seem to have this behaviour. So it might be better to file a bug with the xorg guys...

Comment 2 Giacomo 2012-07-31 07:41:47 UTC

Created attachment 72845 [details]
xorg.conf

Comment 3 Giacomo 2012-07-31 07:43:03 UTC

Created attachment 72846 [details]
xorg.conf

Comment 4 Giacomo 2012-07-31 07:43:24 UTC

System Settings -> Desktop Effects -> Advanced:

- compositing type: OpenGL
- using openGL 2 shaders
- Use VSync

produces:

OpenGL screensavers extremely slow, slowing down the entire machine;
qt examples/opengl/pbuffers extremely slow as soon as you grow the window (or eventually maximize it).

Disabling the Desktop Effects (Alt + Maiusc + F12) restore good performance of the applications mentioned above.

FreeBSD 9.0-RELEASE amd64
X.Org X Server 1.7.7
Release Date: 2010-05-04
X Protocol Version 11, Revision 0

NVIDIA Quadro NVS 285
Option "TwinView" "1"
Driver NVIDIA v.295.59

Comment 5 Giacomo 2012-07-31 07:44:16 UTC

System Settings -> Desktop Effects -> Advanced:

- compositing type: OpenGL
- using openGL 2 shaders
- Use VSync

produces:

OpenGL screensavers extremely slow, slowing down the entire machine;
qt examples/opengl/pbuffers extremely slow as soon as you grow the window (or eventually maximize it).

Disabling the Desktop Effects (Alt + Maiusc + F12) restore good performance of the applications mentioned above.

FreeBSD 9.0-RELEASE amd64
X.Org X Server 1.7.7
Release Date: 2010-05-04
X Protocol Version 11, Revision 0

NVIDIA Quadro NVS 285
Option "TwinView" "1"
Driver NVIDIA v.295.59

Comment 6 Giacomo 2012-07-31 07:45:18 UTC

Sorry I posted two times...

Comment 7 Giacomo 2012-07-31 07:46:07 UTC

Created attachment 72847 [details]
Xorg log file

I Attach the xorg log file.

Comment 8 Martin Flöser 2015-01-23 10:00:09 UTC

The screen locker architecture changed with Plasma 5. The classic screen savers are no longer supported. The 4.x series won't see any further feature development, so this feature request won't be implemented as it doesn't apply to our current version any more.

I want to thank you for your feature suggestion and I'm sorry that we were not able to provide the requested feature before we retired the affected component.