Results of further testing (with very bleeding edge kernel and xorg- edgers PPA) appear to show the problem satisfactorily resolved.
$ uname -a Linux presto 2.6.31-020631rc7-generic #020631rc7 SMP Sat Aug 22 09:51:01 UTC 2009 i686 GNU/Linux $ dpkg -s xserver-xorg-video-intel|grep ersion Version: 2:2.8.0+git20090820.6955fc7a-0ubuntu0sarvatt~jaunty Device section of xorg.conf (the EXA and AccelMethod options are ignored and are hangovers from previous config, so in fact only 'Tiling' option is active): Section "Device" Identifier "Configured Video Device" Driver "intel" Option "AccelMethod" "uxa" Option "EXAOptimizeMigration" "true" Option "MigrationHeuristic" "greedy" Option "Tiling" "true" EndSection Kernel modesetting is On. Boot time seems a little increased compared to user-modesetting, however, and there is a slight cursor glitch (display corruption near the mouse pointer) for a brief period after login. VT-switching is fast and smooth. In Xorg.0.log: (WW) intel(0): Option "AccelMethod" is not used (WW) intel(0): Option "EXAOptimizeMigration" is not used (WW) intel(0): Option "MigrationHeuristic" is not used Results: - glxgears about 340 fps, with drops to 240 and occasional peaks to 400. - ppracer 1280*768 about 24 fps, up from 12. This is the first time I have seen 3D performance improved with no corresponding change in the glxgears number, so it shows the advice to mistrust glxgears as well founded. - Full-screen flash (Youtube etc., 'HD' mode is smooth and OpenGL acceleration appears to be effective Note that the permissions of /dev/dri/card0 are still incorrect: crw-rw----+ 1 root video 226, 0 2009-08-26 00:35 /dev/dri/card0 These permissions should be 666, shouldn't they? But manually changing the permissions and restarting X with kill -9 -1 does not change the graphics performance at all. Another thing I noticed is that it's apparently impossible to synchronise DRI with the screen vertical refresh, as was possible with the 2.6.30.5 kernel. Changing the values in .drirc or using driconf has no effect. I hope this information is of help to other users. I'm now much more confident that the Intel graphics regressions experienced in 9.04 will be resolved to an acceptable level in 9.10, and the process of performance optimisation has, according to blogs, only just got under way. ** Attachment added: "Xorg.0.log" http://launchpadlibrarian.net/30835030/Xorg.0.log -- (UXA) xserver-xorg-video-intel 2D and 3D performance is much reduced from EXA https://bugs.launchpad.net/bugs/416604 You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-intel in ubuntu. _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp