On Fri, Mar 11, 2011 at 10:34, Jonathan Corbet <corbet-ft@xxxxxxx> wrote: > failed to create drawable > Window manager error: Unable to initialize Clutter. > > As far as I can tell, my kernel configuration is the same as Fedora's for > the relevant options - i915, KMS by default, etc. ÂBut the Fedora kernel > works, mine does not. > > Other interesting observations: > > Â- The Xorg.0.log output appears to be identical in both cases. > > Â- The glxgears benchmark (known to be the definitive measure of 3D > Â performance :) runs ten times faster on my custom kernel than on the > Â Fedora kernel. ÂOn my kernel, I don't get the "using vertical sync" > Â message. > > So I'm mystified. ÂAny ideas? ÂMight there be some magic in the Fedora > initrd that I'm missing (I've never used initrd on my systems)? Hrm. From a distance, it's hard to make a diagnosis but I'll try to give you a brain dump of what I know. Basically, the above output seems to indicate that the driver is reporting that it knows how to report the monitor VSync but is failing to actually deliver the signals to OpenGL clients. The driver is supposed to report when it doesn't know about VSync and then Clutter automatically goes in to fallback mode. This is probably a regression in the vanilla sources i915 drive and my guess would be that one of the handful of patches on the Fedora kernel is fixing it: http://koji.fedoraproject.org/koji/rpminfo?rpmID=2451173 Someone on #intel-gfx could probably give you the status of whatever patch you find as the culprit in a matter of seconds. (There's also the fdo bugzilla.) Clutter is trying to time its paint operations to VSync to save power and avoid drawing artifacts. You really should try to figure out what's wrong with your kernel for the best experience but--baring that--there is a work-around: you can export CLUTTER_VBLANK=none before running "jhbuild run gnome-shell --replace" to force Clutter to use its own clock. However, you will get render tearing when moving windows when running in this mode. As for the initramfs, I've just switched from Debian to Fedora so I can't quickly tell you what the role of dracut is in setting up the KMS framebuffer, if any. In Debian, the initramfs does probe the framebuffer modules. However, my guess would be that this is not an issue at all since you see the same Xorg.0.log output. -- test mailing list test@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe: https://admin.fedoraproject.org/mailman/listinfo/test
