対策

kworkerの中でも何がCPUの使用率を上げているのか調べる。

grep . -r /sys/firmware/acpi/interrupts/

私の場合は以下のように出力された。

/sys/firmware/acpi/interrupts/ff_gbl_lock:       0   enabled
/sys/firmware/acpi/interrupts/gpe15:       0   invalid
/sys/firmware/acpi/interrupts/gpe4F:       0   invalid
/sys/firmware/acpi/interrupts/gpe43:       0   invalid
/sys/firmware/acpi/interrupts/gpe7D:       0   invalid
/sys/firmware/acpi/interrupts/gpe71:       0   invalid
/sys/firmware/acpi/interrupts/gpe05:       0   invalid
/sys/firmware/acpi/interrupts/gpe3F:       0   invalid
/sys/firmware/acpi/interrupts/gpe33:       0   invalid
/sys/firmware/acpi/interrupts/gpe6D:       0   disabled
/sys/firmware/acpi/interrupts/gpe61:       0   enabled
/sys/firmware/acpi/interrupts/gpe2F:       0   invalid
/sys/firmware/acpi/interrupts/gpe23:       0   invalid
/sys/firmware/acpi/interrupts/gpe5D:       0   invalid
/sys/firmware/acpi/interrupts/gpe51:       0   invalid
/sys/firmware/acpi/interrupts/gpe1F:       0   invalid
/sys/firmware/acpi/interrupts/gpe13:       0   invalid
/sys/firmware/acpi/interrupts/gpe4D:       0   invalid
/sys/firmware/acpi/interrupts/gpe41:       0   invalid
/sys/firmware/acpi/interrupts/gpe7B:       0   invalid
/sys/firmware/acpi/interrupts/gpe0F:       0   invalid
/sys/firmware/acpi/interrupts/gpe03:       0   invalid
/sys/firmware/acpi/interrupts/gpe3D:       0   invalid
/sys/firmware/acpi/interrupts/gpe31:       0   invalid
/sys/firmware/acpi/interrupts/gpe6B:       0   invalid
/sys/firmware/acpi/interrupts/gpe2D:       0   invalid
/sys/firmware/acpi/interrupts/gpe21:       0   invalid
/sys/firmware/acpi/interrupts/gpe5B:       0   invalid
/sys/firmware/acpi/interrupts/gpe1D:       0   invalid
/sys/firmware/acpi/interrupts/gpe78:       0   invalid
/sys/firmware/acpi/interrupts/gpe11:       0   invalid
/sys/firmware/acpi/interrupts/gpe4B:       0   invalid
/sys/firmware/acpi/interrupts/ff_pwr_btn:       0   enabled
/sys/firmware/acpi/interrupts/ff_slp_btn:       0   invalid
/sys/firmware/acpi/interrupts/gpe0D:       0   invalid
/sys/firmware/acpi/interrupts/gpe68:       0   invalid
/sys/firmware/acpi/interrupts/gpe01:       0   invalid
/sys/firmware/acpi/interrupts/ff_pmtimer:       0   invalid
/sys/firmware/acpi/interrupts/gpe3B:       0   invalid
/sys/firmware/acpi/interrupts/gpe58:       0   invalid
/sys/firmware/acpi/interrupts/gpe2B:       0   invalid
/sys/firmware/acpi/interrupts/gpe48:       0   invalid
/sys/firmware/acpi/interrupts/gpe1B:       0   invalid
/sys/firmware/acpi/interrupts/gpe76:       0   invalid
/sys/firmware/acpi/interrupts/gpe38:       0   invalid
/sys/firmware/acpi/interrupts/gpe0B:       0   invalid
/sys/firmware/acpi/interrupts/gpe66:       0   enabled
/sys/firmware/acpi/interrupts/gpe28:       0   invalid
/sys/firmware/acpi/interrupts/gpe56:       0   invalid
/sys/firmware/acpi/interrupts/gpe18:       0   invalid
/sys/firmware/acpi/interrupts/gpe46:       0   invalid
/sys/firmware/acpi/interrupts/gpe74:       0   invalid
/sys/firmware/acpi/interrupts/gpe08:       0   invalid
/sys/firmware/acpi/interrupts/sci: 2513869
/sys/firmware/acpi/interrupts/gpe36:       0   invalid
/sys/firmware/acpi/interrupts/gpe64:       0   invalid
/sys/firmware/acpi/interrupts/gpe26:       0   invalid
/sys/firmware/acpi/interrupts/error:       0
/sys/firmware/acpi/interrupts/gpe54:       0   invalid
/sys/firmware/acpi/interrupts/gpe16:       0   invalid
/sys/firmware/acpi/interrupts/gpe44:       0   invalid
/sys/firmware/acpi/interrupts/gpe7E:       0   invalid
/sys/firmware/acpi/interrupts/gpe72:       0   invalid
/sys/firmware/acpi/interrupts/gpe06:       0   invalid
/sys/firmware/acpi/interrupts/ff_rt_clk:       0   disabled
/sys/firmware/acpi/interrupts/gpe34:       0   invalid
/sys/firmware/acpi/interrupts/gpe6E:       0   invalid
/sys/firmware/acpi/interrupts/gpe62:       0   enabled
/sys/firmware/acpi/interrupts/gpe24:       0   invalid
/sys/firmware/acpi/interrupts/gpe5E:       0   invalid
/sys/firmware/acpi/interrupts/gpe52:       0   invalid
/sys/firmware/acpi/interrupts/gpe14:       0   invalid
/sys/firmware/acpi/interrupts/gpe4E:       0   invalid
/sys/firmware/acpi/interrupts/gpe42:       0   invalid
/sys/firmware/acpi/interrupts/gpe7C:       0   invalid
/sys/firmware/acpi/interrupts/gpe70:       0   invalid
/sys/firmware/acpi/interrupts/gpe04:       0   invalid
/sys/firmware/acpi/interrupts/gpe3E:       0   invalid
/sys/firmware/acpi/interrupts/gpe32:       0   invalid
/sys/firmware/acpi/interrupts/gpe6C:       0   invalid
/sys/firmware/acpi/interrupts/gpe60:       0   invalid
/sys/firmware/acpi/interrupts/gpe2E:       0   invalid
/sys/firmware/acpi/interrupts/gpe22:       0   invalid
/sys/firmware/acpi/interrupts/gpe5C:       0   invalid
/sys/firmware/acpi/interrupts/gpe50:       0   invalid
/sys/firmware/acpi/interrupts/gpe1E:       0   invalid
/sys/firmware/acpi/interrupts/gpe79:       0   invalid
/sys/firmware/acpi/interrupts/gpe12:       0   invalid
/sys/firmware/acpi/interrupts/gpe4C:       0   invalid
/sys/firmware/acpi/interrupts/gpe40:       0   invalid
/sys/firmware/acpi/interrupts/gpe7A:       0   invalid
/sys/firmware/acpi/interrupts/gpe0E:       0   invalid
/sys/firmware/acpi/interrupts/gpe69:       0   disabled
/sys/firmware/acpi/interrupts/gpe02:       0   invalid
/sys/firmware/acpi/interrupts/gpe3C:       0   invalid
/sys/firmware/acpi/interrupts/gpe30:       0   invalid
/sys/firmware/acpi/interrupts/gpe6A:       0   invalid
/sys/firmware/acpi/interrupts/gpe59:       0   invalid
/sys/firmware/acpi/interrupts/gpe2C:       0   invalid
/sys/firmware/acpi/interrupts/gpe20:       0   invalid
/sys/firmware/acpi/interrupts/gpe5A:       0   invalid
/sys/firmware/acpi/interrupts/gpe49:       0   invalid
/sys/firmware/acpi/interrupts/gpe1C:       0   invalid
/sys/firmware/acpi/interrupts/gpe77:       0   invalid
/sys/firmware/acpi/interrupts/gpe10:       0   invalid
/sys/firmware/acpi/interrupts/gpe4A:       0   invalid
/sys/firmware/acpi/interrupts/gpe39:       0   invalid
/sys/firmware/acpi/interrupts/gpe0C:       0   invalid
/sys/firmware/acpi/interrupts/gpe67:       0   enabled
/sys/firmware/acpi/interrupts/gpe00:       0   invalid
/sys/firmware/acpi/interrupts/gpe3A:       0   invalid
/sys/firmware/acpi/interrupts/gpe29:       0   invalid
/sys/firmware/acpi/interrupts/gpe57:       0   invalid
/sys/firmware/acpi/interrupts/gpe2A:       0   invalid
/sys/firmware/acpi/interrupts/gpe19:       0   invalid
/sys/firmware/acpi/interrupts/gpe47:       0   invalid
/sys/firmware/acpi/interrupts/gpe1A:       0   invalid
/sys/firmware/acpi/interrupts/gpe75:       0   invalid
/sys/firmware/acpi/interrupts/gpe09:       0   invalid
/sys/firmware/acpi/interrupts/gpe37:       0   invalid
/sys/firmware/acpi/interrupts/gpe0A:       0   invalid
/sys/firmware/acpi/interrupts/gpe65:       0   invalid
/sys/firmware/acpi/interrupts/gpe27:       0   invalid
/sys/firmware/acpi/interrupts/gpe55:       0   invalid
/sys/firmware/acpi/interrupts/gpe17:       0   disabled
/sys/firmware/acpi/interrupts/gpe45:       0   invalid
/sys/firmware/acpi/interrupts/gpe7F:       0   invalid
/sys/firmware/acpi/interrupts/sci_not:       0
/sys/firmware/acpi/interrupts/gpe73:       0   invalid
/sys/firmware/acpi/interrupts/gpe07:       0   invalid
/sys/firmware/acpi/interrupts/gpe35:       0   invalid
/sys/firmware/acpi/interrupts/gpe6F: 2513871   enabled
/sys/firmware/acpi/interrupts/gpe63:       0   invalid
/sys/firmware/acpi/interrupts/gpe25:       0   invalid
/sys/firmware/acpi/interrupts/gpe5F:       0   invalid
/sys/firmware/acpi/interrupts/gpe_all: 2513871
/sys/firmware/acpi/interrupts/gpe53:       0   invalid

gpe6Fが数字が大きく、enabledになっており、これがCPU使用率を上げている。

以下のコマンドを実行することで、CPU使用率は下がる。

su
echo "disable" > /sys/firmware/acpi/interrupts/gpe6F

しかしこれでは起動するたびに同じコマンドを実行してやらなければ改善されないので、crontabで起動時に自動実行されるようにする。

su
crontab -e

crontabのエディタはviらしいので、操作はviと同じ。
空のファイルが開かれるので、

@reboot echo "disable" > /sys/firmware/acpi/interrupts/gpe6F

を追加する。