All CPUs always running at profhz
bf1783 at googlemail.com
Mon Mar 7 15:01:17 UTC 2011
> I have systems running 7.4 and 8.2. The newer ones (in terms of age of
> hardware) are always running at profhz, i.e., when executing a "systat
> -vm 1" I see that all cores always get profhz interrupts per second.
> An older machine running 7.4 is running at hz (which for this machine I
> set to kern.hz=200 in loader.conf).
> Using ps -o ...,flags,... I see that no process has profiling turned on.
> Why is this so?
> Especially on laptops, I'd like to save power by lowering the interrupt
I have not analyzed this problem. However, by using 9-CURRENT, together with
, removing DEVICE_POLLING from my kernel, and reducing kern.hz to 100,
I was able to achieve reported interrupt rates of ~35-40 Hz on my UP
machines when idle, and substantial reductions when the machines were
loaded, as well. When used with other power-saving measures, this was
a big help.
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