Ondemand vs. Performance CPU Governing For AMD FX CPUs On Linux 3.17

[grigi]

Do I have to restart the PC or is it applied immediately?

Immediately.

it doesn't persist across boots, so you should put it in a startup script to run after every boot (very much distro-dependant)

[tomtomme]

Immediately.

it doesn't persist across boots, so you should put it in a startup script to run after every boot (very much distro-dependant)

thanks!
did some testing with the witcher 2 port and it helped!

[grigi]

Did you try and post images? I have some png file names in the email.

[tomtomme]

Did you try and post images? I have some png file names in the email.

default settings 95 and 1


15 and 100



HD 7950 core2quat @ 3ghz
radeonSI, Mesa 10.4, llvm3.6svn, hyperz, kernel 3.16.1
FPS graphs / screenshots from GALLUM_HUD after easy arena fight in the witcher 2 beta 5;
low settings, GL 3.2, 1080p, vsync

[stqn]

I?ve also been using up_threshold = 50 and sampling_down_factor = 10 for a long time on my Core i3*. It used to make Flash behave correctly several years ago, and recently I?ve also seen that it makes ondemand very close to performance in terms of FPS for The Witcher 2, while the default 95/1 makes you lose 5-10% in FPS.
[*] First gen Core i processors do not use intel_pstate.

[stqn]

default settings 95 and 1


15 and 100



HD 7950 core2quat @ 3ghz
radeonSI, Mesa 10.4, llvm3.6svn, hyperz, kernel 3.16.1
FPS graphs / screenshots from GALLUM_HUD after easy arena fight in the witcher 2 beta 5;
low settings, GL 3.2, 1080p, vsync

I?m surprised there is so little difference. Perhaps your GPU and video driver are the limiting factor and you should reduce the resolution and disable vsync to better see the impact of the ondemand settings.

[tomtomme]

I?m surprised there is so little difference. Perhaps your GPU and video driver are the limiting factor and you should reduce the resolution and disable vsync to better see the impact of the ondemand settings.

little? I would guess thats a 20% improvement. Pretty impressive without buying new hardware...
sadly I can?t disable vsync makes because in video sequences then I have several 100 fps and that makes the graph unreadable because I do not know how to limit its fps maximum / scale.

[stqn]

little? I would guess thats a 20% improvement.

Ah well, all I*see in these graphs is you get 61 FPS with the default settings and only 60 with the optimized settings?