Re: 2.6.17-rc3: cpufreq-set -g ondemand does not work
> > Maybe this helps:
> > http://forums.gentoo.org/viewtopic-t-462417.html
>
> Yes, it does.
>
> "JoseJX" write there that ondemand and conservative cannot be used
> on 7xx/74xx processors because of the time required to switch speeds.
The reason seems to be a rather conservative assumption on the latency
('probably takes forever') - does it really take more than 10 ms to switch
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'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 ...
> Powernowd is recommended.
Indeed.
Michael
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