Bug 790099

Summary:	kernel-3.2.5-3 i915 compositing performance regression
Product:	[Fedora] Fedora	Reporter:	Rex Dieter <rdieter>
Component:	xorg-x11-drv-intel	Assignee:	Adam Jackson <ajax>
Status:	CLOSED NOTABUG	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	rawhide	CC:	ajax, gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, xgl-maint
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-02-13 17:25:43 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Rex Dieter 2012-02-13 16:38:07 UTC

$ rpm -q kernel
kernel-3.2.3-2.fc16.x86_64
kernel-3.2.2-1.fc16.x86_64
kernel-3.2.5-3.fc16.x86_64

Each kernel prior to kernel-3.2.5-3.fc16.x86_64 performed kwin desktop effects and compositing quite well.  Now, there's are noticeable delays all over the place, sometimes as long as several seconds to min/max windows, draw menus, etc...

http://www.smolts.org/client/show/pub_e0f76fc1-43db-4621-afa3-24a946fac413

in particular uses,
Intel Corporation Mobile 945GM/GMS/940GML Express Integrated Graphics Controller

Comment 1 Rex Dieter 2012-02-13 16:42:02 UTC

$ dmesg | grep i915
[    1.341303] i915 0000:00:02.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
[    1.341389] i915 0000:00:02.0: setting latency timer to 64
[    2.308605] [drm] Initialized i915 1.6.0 20080730 for 0000:00:02.0 on minor 0

Comment 2 Dave Jones 2012-02-13 16:59:34 UTC

3.2.3 added these i915 commits..

04115a9dee110b52a8eaa556c574022fa3bf4704 
ba68e086223a5f149f37bf8692c8cdbf1b0ba3ef

Comment 3 Rex Dieter 2012-02-13 17:25:43 UTC

OK, seems this is at least partly a problem of my own making, was testing workarounds for some odd focus issues in kdm (bug #631767), and added to kdmrc
GrabServer=true
and in this greatly impacts compositing performance as a side-effect apparently (just a bit less noticeable on the older kernels).

so, let's just take that off the table, and consider this bug self-induced for now.