Need help dissecting Intel GM45 regression

Question

Performance regression on Gen4 Intel GM45 GMA4500MHD
https://bugs.freedesktop.org/show_bug.cgi?id=77372
Suspected components:
graphics stack
Gnome shell
Note:
The maintainer could not reproduce the bug on his Intel GM45 system.
It's beyond my skills to handle this on my own. I'd be really grateful if someone could assist me. I know that in arch/pacman partial upgrades are not supported so I don't even know whether it is possible to conduct the troubleshooting on arch. Even if not, I would still seek help here, among archers.
To give you an idea, if I go for a 'we use fedora for this and first we upgrade just gnome shell' I wouldn't be sure what package names to give to yum to achieve this, e.g. should it be the entire gnome group?  I would know how to blacklist some package to prevent it from upgrading though.
Last edited by bbarcher (2014-05-05 19:58:01)

Answer 1

Thank you for your reply.
drcouzelis wrote:Is direct rendering enabled? What is the output of "glxinfo | grep render"?
# glxinfo | grep render
direct rendering: Yes
GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
OpenGL renderer string: Mesa DRI Mobile Intel® GM45 Express Chipset
GL_MESA_ycbcr_texture, GL_NV_blend_square, GL_NV_conditional_render,
drcouzelis wrote:You focus a lot on GNOME3. Do other applications experience the poor performance?
Yes, e.g. scrolling in other apps is also affected. Haven't checked on windowed games yet.
drcouzelis wrote:The first step is to downgrade packages until the desired behaviour returns.
This I know. What I don't know is the >list of packages< for each >investigated component<.  Investigated components being:
1. Graphics stack.
(and its sub-components)
1a. Intel drivers.
1b. other components of graphics stack (?)
2. Kernel.
3. Gnome shell (I assume mutter, clutter etc. are integral parts of Gnome shell).
Another thing I don't know is the order in which I should downgrade the components. My noob guts tell me we should rule out gnome first.
Also, wouldn't it be easier to install clean Fedora 18, which ran smoothly, and then upgrade one component at a time instead of doing downgrades? It would require just 'yum upgrade <package name/group name>'. AFAIK downgrades are potentially more troublesome. Especially for a noob.
drcouzelis wrote:Does that bug report say that the time acceleration worked correctly it was in Feb 2013? Is that correct?
If I remember correctly, yes, that's correct. Clean install of Fedora 18. Before Fedora 19 has been released some updates*** to Fedora 18 degraded the performance and it never got back to the old performance level on my system since then.
***read as: some linux components updated upstream at the time, i.e. it was not and it is not Fedora-specific)
Last edited by bbarcher (2014-04-15 19:54:57)