On Tue, May 30, 2000 at 05:46:54PM +0200, Technolord wrote:
> > clock-interrupts.  Having the CPU interrupted and power-ed up 100
> > times per second has got to take its toll.  Has anyone played with
> > tuning the kernel for even more power savings?
> Actually, RTC interrupts 1024 times a second, system clock 18.2 times a
> second, and I'd guess something else bothers the CPU some dozen of times
> a second, like keyboard/disk/network/mouse/vga/power/today_is_a_nice_day
> and so on. I'd guess masking out the RTC might help a lot, but long time
> it was since I last touched a PIC...

Well, on i386, there are 100 clock interrupts / s and nothing else while
the system is idle (easy to check using systat vmstat).

I don't think these interrupts really cause too much waste of energy.
The interrupt routines are fast, so the CPU still sleeps most of the
time.  100 times per second is a _very_ slow rate to the modern CPU's
which run at 500+ MHz.

The added code to stop clock interrupts and still keep the system
functioning as before might consume more energy than what was saved
by the skipped clock interrupts..

  -jm