[arch-general] powertop vs archlinux vs ubuntu

[Brendan Long]

On 02/21/2010 04:55 PM, Xavier Chantry wrote:
> On Mon, Feb 22, 2010 at 12:42 AM, Stefano Z. <mie.iscrizioni at gmail.com> wrote:
>   
>> hi
>>
>> i've bought a new notebook (hp pavilion dm1-1150sl) and installed
>> archlinux.
>> i have see a strange thing with powertop, i'm running the vanilla arch kernel26,
>> and i have see this behaviour:
>> Cn                Avg residency       P-states (frequencies)
>> C0 (cpu occupata)      (31,6%)
>> C0                0,0ms ( 0,0%)
>> C1 mwait          0,1ms ( 0,7%)
>> C4 mwait          0,0ms (67,8%)
>> Wakeups-from-idle per second : 31483,5  interval: 10,0s
>> ---
>> as you can see, i have a LOT of wakeups per seconds very low c1 states
>> lot of c0 and c4 states,
>> a wattmeter tell me that archlinux consume about 25/26watt
>> Then i have boot a live ubuntu distro and see this:
>> Cn                permanenza media    P-state (frequenze)
>> C0 (cpu occupata)      ( 0,6%)
>> polling           0,0 ms ( 0,0%)
>> C1 mwait         26,7 ms (68,6%)
>> C4 mwait          1,2 ms (30,8%)
>> Wakeup-da-idle al secondo: 281,3        intervallo: 15,0s
>> ---
>> as you can see  the wakeups are a LOT lower than on arch and we have
>> lot of c1 and c4 state,
>> power consumption is about 20W, the same that i have with win7 (about 18/20w).
>> For meaning about cX state see here:
>> http://www.lesswatts.org/projects/powertop/powertop.php
>>
>> thanks!
>>
>>     
> You didn't give enough information so we will need to check the basis :
> - which cpufreq driver and governor are you using in both cases (check
> cpufreq-info)
> - what processes does powertop show as causes for wakeups ?
> - what processes does top show in term of cpu usage ?
>
> Here is what I got in the last few minutes when i was writing this :
> C4 mwait          3.4ms (92.5%)          800 Mhz    98.0%
> Wakeups-from-idle per second : 279.4    interval: 10.0s
>
> I have a core 2 duo with acpi-cpufreq loaded and conservative governor.
> $ grep cpufreq /etc/rc.conf
> MODULES=(acpi-cpufreq)
> DAEMONS=(syslog-ng net-profiles crond dbus hal alsa cpufreq storage-fixup)
> $ grep governor /etc/conf.d/cpufreq
> # valid governors:
> governor="conservative"
>   
They may just not have cpu-freq-utils installed maybe? I'm using
laptop-mode-tools with compiz and GNOME running (but not doing anything)
and it's saying 99.2% C4, 0.8% C0. This is with another Core2 and
laptop-mode is set to use the powersave governor on battery (which is
how I tested). When I plug it in, it jumps up to 25%, but I don't really
care how active the processor is when it's on battery.