On Feb 19, 2008 12:09 PM, Florian Philipp <[EMAIL PROTECTED]>
wrote:
>
> On Tue, 2008-02-19 at 11:28 +0100, b.n. wrote:
> > Lowe Schmidt ha scritto:
> > > Hi.
> > >
> > > I'm planning on buying myself a MacBook and I'm just wondering if
> anyone
> > > knows how many hours I will get out of it if I run Gentoo. I mainly
> use
> > > a bunch
> > > of terminals, gvim and some lightweigth gtk app so nothing heavy going
> on.
> > >
> > > All input appreciated
> >
> > My Macbook Pro with light, normal usage lasts about three hours (OS X
> > lasts at least one hour more).
> >
> > m.
>
> Have you found any reason for this discrepancy? I'd suspect them to be
> on par with the right tuning.
>
Are you doing any kind of CPU frequency scaling? In the kernel (I use gentoo
sources) configuration enable
Power Management
- CPU frequency scaling
- performance (is selected as default)
- ondemand governor
- conservative
- ACPI Processor P-States driver
- Intel Enhanced SpeedStep
This enables frequency scaling... this works for my Core2 desktop so I
suspect it should work for the mac book too.
To select the actual cpu scaling governor to use, you can do the following
(as root)
echo ondemand > /sys/devices/system/cpu/cpu(n)/cpufreq/scaling_governor
where you need to this for all the cores... for my Core 2 desktop I have
cpu0 and cpu1.
You can select between ondemand, conservative and performance. Try both
ondemand and conservative... My guess is there will be little difference in
power consumption between the two and ondemand may be better for response
time sensitive loads (typical desktop usage).
I keep the above command in /etc/conf.d/local.start so that I get the CPU
freq scaling goodness on every boot :)
# /etc/conf.d/local.start
# This is a good place to load any misc programs
# on startup (use &>/dev/null to hide output)
gov=ondemand
echo "Switching to the '$gov' cpu frequency scaling governer."
echo $gov > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo $gov > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor
_r
