System information
Power Management 141
available frequency steps: 3.40 GHz, 2.80 GHz
available cpufreq governors: conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 2.80 GHz and 3.40 GHz.
The governor "performance" may decide which speed to use
within this range.
current CPU frequency is 3.40 GHz.
Using the appropriate options, you can view the current CPU frequency, the mini-
mum and maximum CPU frequency allowed, show the currently used CPUfreq pol-
icy, the available CPUfreq governors, or determine the CPUfreq kernel driver used.
For more details and the available options, refer to the cpufreq-info man page or
run cpufreq-info --help.
11.3.1.2 Modifying Current Settings with cpufreq-
set
To modify CPUfreq settings, use the cpufreq-set command as root. It allows
you set values for the minimum or maximum CPU frequency the governor may select
or to create a new governor. With the -c option, you can also specify for which of the
processors the settings should be modified. That makes it easy to use a consistent poli-
cy across all processors without adjusting the settings for each processor individually.
For more details and the available options, refer to the cpufreq-set man page or
run cpufreq-set --help.
11.3.2 Using the cpupower Tools
After installing the cpupower package, view the available cpupower sub-
commands with cpupower--help. Access the general man page with
mancpupower, and the man pages of the subcommands with mancpupow-
er-subcommand.
The subcommands frequency-info and frequency-set are mostly equiva-
lent to cpufreq-info and cpufreq-set, respectively. However, they provide
extended output and there are small differences in syntax and behavior:
Syntax Differences Between cpufreq* and cpupower
• To specify the number of the CPU to which the command is applied, both com-
mands have the -c option. Due to the command-subcommand structure, the place-
ment of the -c option is different for cpupower: