[ltp] T60 battery

[Michael Gaber]

Carles Pina i Estany schrieb:
> Hello,
> 
> On Nov/26/2006, Michael Gaber wrote:
>> Carles Pina i Estany schrieb:
>>> Hi!
>>>
>>> echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
>>> echo 1000000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed
>>>
>>> echo userspace > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor
>>> echo 1000000 > /sys/devices/system/cpu/cpu1/cpufreq/scaling_setspeed
>>>
>>> echo 0 > /sys/devices/system/cpu/cpu1/online
>>>
>>> aticonfig --set-powerstate=1
>>>
>> why userspace? i think ondemand/conservative is much more useful, 
>> because the cpu jumping up in the frequency for a second wouldn't cost 
>> as much energy as running for several seconds at low speed,
> 
> I have two icons in the desktop, when I want I setup in "low speed" or
> "high speed". I am not "jumping" from one frequency to other one... is
> it a correct approach? (always thinking to control it "by hand", not
> "automatic")
> 
> Thanks,
> 
yeah, and that's not always the best approach.

the CPU has three sleep states C1 to C3, where C1 uses much more power 
as C3.
if you regulate down the CPU to 1GHz and it needs to come up from C3 to 
C1 for much longer to finish a task than it would need if it just scaled 
up for a shorter period of time with automatic scaling enabled you would 
affectively need more power if you controll it by hand