Managing CPU throttling

[Matthew Garrett]

On Sun, 2004-10-24 at 11:08 -0500, kaput wrote:

> However, I would like to be able to have a little more control over
> throttling. For example, when running Tribes 2, the engine recognizes
> that the CPU is running at 1200 mhz. The problem is after the engine is
> started, the CPU jumps to 2200, which causes the engine to start running
> too fast.

Fundamentally, this is a bug in the application. Linux makes no
guarantees about the CPU speed staying constant, and the kernel doesn't
always know that it's changed.

> I know that gnome-cpufreq-applet supports changing frequencies, but the
> applet must be run as root (and I'm not even sure if support for this is
> included in the Ubuntu binary). Supposedly, the author is about to
> releasing a version that runs as user, but prompts for the user
> password.

The long-term solution to this is likely to involve adding extra
platform information to HAL, and then having applications request CPU
speeds via a DBUS message. Sadly, there isn't currently a short-term
solution :)

-- 
Matthew Garrett | mjg59 at srcf.ucam.org