Comment # 8
on bug 70706
from Dennis Schridde
(In reply to comment #7)
> (In reply to comment #5)
> > To me this issue seems to appear randomly - sometimes KDE starts with
> > working compositing, but most often it does not.
>
> Same, here.
> When it starts _with_ compositing, then error message appears.
> _Without _ compositing glxinfo runs OK and GL performance is nearly 25%
> better!
In the current session I did not get compositing but the mentioned message in
~/.xession-errors:
kwin(2492): Failed to get visual from fbconfig
kwin(2492) KWin::OpenGLBackend::setFailed: Creating the OpenGL rendering
failed: "Could not initialize the buffer"
kwin(2492): Failed to initialize compositing, compositing disabled
glxinfo currently does not work, either:
Error: couldn't find RGB GLX visual or fbconfig
Error: couldn't find RGB GLX visual or fbconfig
name of display: :0
[...]
So the current session seems to be a case of "without compositing, with glxinfo
error". Which also seems to make sense: Something is preventing GL apps from
working, which also affects glxinfo.
A quick test shows that EGL does not seem to be affected:
$ eglinfo
EGL API version: 1.4
EGL vendor string: Mesa Project
EGL version string: 1.4 (Gallium)
EGL client APIs: OpenGL OpenGL_ES OpenGL_ES2
[...]
Also the X11 variants of the *gears (egl,es1,es2) programs work:
$ eglgears_x11
EGL_VERSION = 1.4 (Gallium)
But the "screen variants do not (though I do not remember ever before testing
them, so I cannot tell whether this is a regression):
$ eglgears_screen
EGL_VERSION = 1.4 (Gallium)
EGLUT: failed to choose a config
I can confirm this with KWin (stripped from unrelated output):
$ kwin
kwin(3945): Failed to get visual from fbconfig
kwin(3945) KWin::OpenGLBackend::setFailed: Creating the OpenGL rendering
failed: "Could not initialize the buffer"
QObject::connect: Cannot connect (null)::resetCompositing() to
KWin::Compositor::restart()
kwin(3945): Failed to initialize compositing, compositing disabled
kwin(3945): Consult
http://techbase.kde.org/Projects/KWin/4.0-release-notes#Setting_up
$ kwin_gles
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD REDWOOD
OpenGL version string: OpenGL ES 3.0 Mesa 9.2.4
OpenGL shading language version string: OpenGL ES GLSL ES 3.0
[...]
> So is there a possibility, that we can disable compositing on the fly, when
> GL apps starts?
I think that is a completely unrelated issue that belongs on
https://bugs.kde.org/ and should be reported against KWin.