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Re: 2.6.17-rc3: cpufreq-set -g ondemand does not work



> > speeds? The code path on the 7447A models appears to have a settle delay
> > of 1 ms after the feature call (which boils down to an OUTB, basically),
> > another 0.1 ms after the low_choose_7447a_dfs call which shouldn't take
> > very long either. Am I missing something, Ben?
>
> I'm being over conservative bcs of the voltage change

That's the 1 ms, after which the speed switch happens. Do you think the
voltage switch actually takes longer to settle than this?

> > I'd not be surprised if the latency was as low as 2 ms total - can we
> > profile this reliably in some way? I guess I'll just set the latency to 5
> > ms and see what happens ...
>
> Last time I looked the on-demand governor was using a workqueue...
> anything that has a latency of more than a few dozen usec in a workqueue
> shall be shot...

That may be right - it's probably the reason for the latency cutoff at 10
ms. People might not be impressed if they try ondemand switching :-)

Anyway: is it safe to try, or will I fry my system board?

	Michael



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