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Date: Wed, 30 Nov 2005 20:27:52 +0000
From: Marco Calviani <marco.calviani@gmail.com>
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Cc: 
Subject: Re: cpufreq and changing driver
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Hi Bruno,

> The ondemand governor is basically an implemation of the following
> algorithm:
>
> There is a counter, say count.
>
> at each given fixed intervall:
> if (idle less than a watermark) {
>     frequency full
>     reinitialise count to 10
> } else if (idle more than another watermark) {
>     decrement count
>     if count is 0 {
>         down one step the frequency
>     }
> else reinitilize count to 10
>
>
> Note that in the latter case, the down step is performed only
> after 10 such comparison.  In other word, intervall is ten times
> larger for the down side than the full frequency one.
>
> This work well when you can perform, say, 20 to 50 transitions per
> second.  Otherwise, it is pretty bad.
>

Thanks very much!
 But i'm not understanding if this high number of transitions are a
problem from the hardware point of view or from the software
implementation in freeBSD?

Best regards,
MC