I've been lurking on this list for a while now, but a few friends of
mine encouraged me to post a chunk of code I wrote...

I wrote a simple "dynamic" frequency governor for use on my non-mobile
P4 laptop, since the demandbased governor patch seems to be targeted at
mobile CPUs. (...and doesn't work for me :)

I've been using the "dynamic" governor on my machine with the
p4-clockmod driver, and it works beautifully. I don't notice any
slowdown in X/Gnome2, though I'm sure there is quite a bit. I do however
notice significant drops is heat output and a small yet noticeable
increase in battery life.

The module itself just polls idle jiffies every 100ms, and bumps up the
frequency if there's less than 20% idle, and down if there's more than
80%.

I've made a quick patch that should apply cleanly to 2.6.0-test9. Also
included is the raw code, however ugly it may be.

From previous posts, I've gathered that:
1) This kind of stuff is probably patented, so it will never be merged
anywhere. Oh, well.
2) People seem to prefer userspace tools to govern frequency. As far as
I can tell, the kernel-based solution should use way less overhead, and
doesn't run into certain limitations.

Comments, questions? Please let me know,

jon anderson