powerd effectiveness

Daniel O'Connor doconnor at gsoft.com.au
Thu Jan 12 15:41:19 PST 2006

On Fri, 13 Jan 2006 00:10, Bruno Ducrot wrote:
> > Thats the correct one, it is 75mhz. I was suspecting hardwares
> > limitations in terms of modulating the frequency quickly enough. Just
> > wanted to make sure.
> What you have noticed is acpi_throttle(4).  The combinaison of
> some VIA chipset and AMD processors give 16 frequencies.
> powerd(8) is not designed for thermal stuff, and will never be.
> It's up to acpi_thermal(4) to cool the processor if needed.
> Note that I think acpi_throttle(4) can only be used for cooling a
> processor. I don't think it is usefull for power comsuption at all for
> which
> powerd(4) is designed.  Some other people may have different opinion of
> course.

I don't see how reducing power consumption could NOT affect the temperature.

Nearly all of the energy going into the CPU is disipated as heat.

> You may also want to check if sysutlis/fvcool can help you if setting
> the above sysctl is not possible (but don't mix the two).

How come?
(I am just curious :)

Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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