cpufreqポリシーの範囲を変更するには?
$ cpupower frequency-info
analyzing CPU 0:
driver: powernow-k8
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 0 1
maximum transition latency: 109 us
hardware limits: 800 MHz - 2.00 GHz
available frequency steps: 2.00 GHz, 1.80 GHz, 1.60 GHz, 800 MHz
available cpufreq governors: conservative ondemand userspace powersave performance schedutil
current policy: frequency should be within 800 MHz and 800 MHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency: Unable to call hardware
current CPU frequency: 800 MHz (asserted by call to kernel)
boost state support:
Supported: no
Active: no
ハードウェア制限は2GHzですが、ポリシー制限は800であることがわかります。努力する
$ sudo cpupower frequency-set --max 2000000
Setting cpu: 0
Setting cpu: 1
しかし、効果はありません:
$ cpupower frequency-info --policy
analyzing CPU 0:
current policy: frequency should be within 800 MHz and 800 MHz.
The governor "ondemand" may decide which speed to use
within this range.
値を直接エコーしようとしています。
echo 2000000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
サイコロがありません。
問題はxubuntu 17.04 x86_64と最新のMajnaro i686で発生するため、ディストリビューションに限定されません。