Re: Power Saving

From: Stephen Clark
Date: Mon Nov 19 2007 - 20:05:40 EST


Dave Jones wrote:

On Mon, Nov 19, 2007 at 07:41:31PM -0500, Stephen Clark wrote:
> Hello List,
> > I am trying to get throttling to work on the following processor

I think by throttling, you actually mean changing frequency/voltage ?
(throttling is something else, where the CPU skips every n cycles,
which doesn't actually save any power)

> with linux 2.6.17-1.2142_FC4 with no luck.

wow. that's a prehistoric kernel.

> AMD Athlon(tm) XP 1700+

you lose. Only the mobile athlons supported scaling their speed.
And even then, only if the BIOS supported it with the correct tables.
(Typically this means, "only laptops").

Dave



well what about the info from /proc/

cat /proc/acpi/processor/CPU0/info
processor id: 0
acpi id: 0
bus mastering control: no
power management: yes
throttling control: yes
limit interface: yes

and:
cat /proc/acpi/processor/CPU0/throttling
state count: 2
active state: T0
states:
*T0: 00%
T1: 50%

and:
[root@joker ~]# cat /proc/acpi/processor/CPU0/power
active state: C2
max_cstate: C8
bus master activity: d18324c9
states:
C1: type[C1] promotion[C2] demotion[--] latency[000] usage[01340140]
*C2: type[C2] promotion[--] demotion[C1] latency[090] usage[02980043]

????
Steve

--

"They that give up essential liberty to obtain temporary safety, deserve neither liberty nor safety." (Ben Franklin)

"The course of history shows that as a government grows, liberty decreases." (Thomas Jefferson)



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