Bug 29704

== Following setup:
* GMA945 graphics (agpgart-intel 0000:00:00.0: Intel 945GM Chipset)
* intel-dri 7.8.2-1
* dri2proto 2.3-1
* xf86driproto 2.1.0-1
* xf86-video-intel 2.12.0-1
* xorg-server 1.8.1.902-1
* xorg-server-utils 7.5-4

== General description:
For months I've been experiencing bad performance with this graphics chipset and compiz and other 3D-Applications. At least since kernel 2.6.32 or somesuch. The Problems include massive framedrops, artifacts and overall bad performance.

== Detail description:
I've tried several setups, and some behave different than others. The biggest difference is between using direct or indirect rendering. As a very simple test, I just use a .xinitrc that contains nothing but one line. Here's the symptoms:

A) Direct rendering disabled:
* Bad overall performance
* The test with just glxgears (.xinitrc contains "LIBGL_ALWAYS_INDIRECT=true exec glxgears") shows the gears NOT turning for most of the time. It's just a static picture of the gears, occasionally showing a different frame. Output reports about 25-35 fps.
* No artifacts or redraw problems

B) Direct rendering enabled:
* Performance
* The test with just glxgears (.xinitrc contains just "exec glxgears") shows the gears not "turning" really, because the framerate is utterly low, but something's happening. Reported framerate is 7-9 fps.
* Redrawing problems, totally reproducible: For example when in vim, hitting ENTER at the start of a line that contains something will not clear that line but in fact show it double, as seen on this screenshot, where the line with marked appears double instead of empty. Clicking on a different window at that point will redraw this one.
--> see this screenshot: http://stuff.moritzg.ch/dri-redrawproblem.png
* Artifacts: Happen at random. Worst yet was the one in the screenshot below but there are varying grades. Sometimes only the fonts get garbled, sometimes there are lines and everything.
--> see this screenshot: http://stuff.moritzg.ch/dri-artifacts.png

Things that didn't make a difference:
* Option "Tiling" true or false doesn't make a difference
* Options "AxxelMethod", "PageFlip" or "TripleBuffer" aren't used anymore apparently.
* As said, it doesn't make a difference if I run glxgears or anything inside compiz or standalone from .xinitrc, the symptoms (not moving if DRI disabled, abysmal framerate when DRI enabled) remain the same.
* There's a constant drizzle of "composite sync not supported" in my dmesg. It gets spammed there like once per minute or so

== Files and outputs:
grep "EE" /var/log/Xorg.0.log:
nothing

grep "WW" /var/log/Xorg.0.log:
[  9279.762] (WW) The directory "/usr/share/fonts/OTF/" does not exist.

dmesg | grep intel:
intel_rng: FWH not detected
agpgart-intel 0000:00:00.0: Intel 945GM Chipset
agpgart-intel 0000:00:00.0: detected 7932K stolen memory
agpgart-intel 0000:00:00.0: AGP aperture is 256M @ 0xd0000000
fb0: inteldrmfb frame buffer device

dmesg | grep drm:
[drm] Initialized drm 1.1.0 20060810
[drm] set up 7M of stolen space
[drm] initialized overlay support
fb0: inteldrmfb frame buffer device
drm: registered panic notifier
[drm] Initialized i915 1.6.0 20080730 for 0000:00:02.0 on minor 0

/etc/X11/xorg.conf:
Section "ServerLayout"
	Identifier     	"X.org Configured"
	Screen      0  	"Screen0" 0 0
EndSection

Section "Device"
	Option "Tiling" "false"
	Identifier  "Card0"
	Driver      "intel"
EndSection

Section "Screen"
	Identifier "Screen0"
	Device     "Card0"
	Monitor    "Monitor0"
	DefaultDepth 24
	SubSection "Display"
		Depth     24
		Modes "1440x900"
		#Virtual 1440 1924
	EndSubSection
EndSection

This issue had me bugging ever since it occured months ago and my hopes of it getting fixed at some time were never fulfilled. It would be great if this could be fixed. If any additional info or testing is needed, please tell me. Thanks!