RFC: powerd algorithms enhancements

[Alexander Motin]

Ian Smith wrote:
> We're now seeing cpus that can vary freq, with absolute and relative 
> cpufreq drivers enabled, in ratios up to 32:1 or so, so the advice, 
> apart from 'disable powerd' :), seems to be to at least try setting 
> cpufreq.lowest to some reasonable speed for workload, maybe 300MHz?

I surely should not be the default, but it is reasonable if systems 
should have some guarantied minimal performance.

PS: At any modern SMP/HTT system, even if scheduler is unable to manage 
this IRQ situation, powerd running on different CPU will rise clock to 
required level just in second. It is hard to lock-out all CPUs same 
time. It's surely not solution, but still...

-- 
Alexander Motin