[arch-general] CPU frequency scaling issue

Ralf Mardorf ralf.mardorf at rocketmail.com
Sat Dec 13 22:22:12 UTC 2014


Hi,

any idea why CPU frequency scaling doesn't work for 3.14.25-rt22 [1]
and why it does work for 3.17.6 [2]?

Regards,
Ralf

[1]
[rocketmouse at archlinux ~]$ uname -rm
3.14.25-rt22-1-rt x86_64
[rocketmouse at archlinux ~]$ zgrep CONFIG_CPU_FREQ /proc/config.gz 
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_GOV_COMMON=y
CONFIG_CPU_FREQ_STAT=m
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=m
[rocketmouse at archlinux ~]$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
performance
performance
[rocketmouse at archlinux ~]$ echo ondemand | sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
[sudo] password for rocketmouse: 
ondemand
tee: /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor: Invalid argument
[rocketmouse at archlinux ~]$

[2]
[rocketmouse at archlinux ~]$ uname -rm
3.17.6-1-ARCH x86_64
[rocketmouse at archlinux ~]$ zgrep CONFIG_CPU_FREQ /proc/config.gz 
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_GOV_COMMON=y
CONFIG_CPU_FREQ_STAT=m
CONFIG_CPU_FREQ_STAT_DETAILS=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=m
[rocketmouse at archlinux ~]$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
ondemand
ondemand
[rocketmouse at archlinux ~]$ echo performance | sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
[sudo] password for rocketmouse: 
performance
[rocketmouse at archlinux ~]$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
performance
performance
[rocketmouse at archlinux ~]$ echo ondemand | sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
ondemand
[rocketmouse at archlinux ~]$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
ondemand
ondemand
[rocketmouse at archlinux ~]$


More information about the arch-general mailing list