CPU offline but power consumption increased?

From: Andika Triwidada
Date: Sat Apr 07 2007 - 00:24:34 EST


http://andika-lives-here.blogspot.com/2007/03/eksperimen-cpu-hotplug-dan-konsumsi.html

* initial setup:
root@hokage:~# cpufreq-set -d 1.666g
root@hokage:~# cpufreq-set -u 1.666g
root@hokage:~# cpufreq-set -g userspace
root@hokage:~# cpufreq-info
cpufrequtils 002: cpufreq-info (C) Dominik Brodowski 2004-2006
Report errors and bugs to linux@xxxxxxxx, please.
analyzing CPU 0:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time: 0 1
hardware limits: 1000 MHz - 1.67 GHz
available frequency steps: 1.67 GHz, 1.33 GHz, 1000 MHz
available cpufreq governors: userspace, powersave, ondemand,
conservative, performance
current policy: frequency should be within 1.67 GHz and 1.67 GHz.
The governor "userspace" may decide which speed to use
within this range.
current CPU frequency is 1.67 GHz (asserted by call to hardware).
analyzing CPU 1:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time: 0 1
hardware limits: 1000 MHz - 1.67 GHz
available frequency steps: 1.67 GHz, 1.33 GHz, 1000 MHz
available cpufreq governors: userspace, powersave, ondemand,
conservative, performance
current policy: frequency should be within 1.67 GHz and 1.67 GHz.
The governor "userspace" may decide which speed to use
within this range.
current CPU frequency is 1.67 GHz (asserted by call to hardware).

root@hokage:~# grep rate /proc/acpi/battery/BAT1/state
present rate: 1693 mA


* turn off CPU#1
root@hokage:~# echo 0 > /sys/devices/system/cpu/cpu1/online
root@hokage:~# grep rate /proc/acpi/battery/BAT1/state
present rate: 2084 mA

* turn CPU#1 back on:
root@hokage:~# echo 1 > /sys/devices/system/cpu/cpu1/online
root@hokage:~# grep processor /proc/cpuinfo
processor : 0
processor : 1
root@hokage:~# grep rate /proc/acpi/battery/BAT1/state
present rate: 1653 mA


Question: is that normal? I thought power consumption will be
automatically reduced if one core offlined.

Thanks.
Andika
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