CPU Frequency Scaling
Given a minimal install, CPU frequency scaling support is not installed.
# yum install cpuspeed cpufrequtils
The default 'acpi_cpufreq' module will be loaded for Intel CPU's, and the default governor is 'ondemand'. The cpuspeed system service defaults to being enabled.
# service cpuspeed start Enabling ondemand cpu frequency scaling: [ OK ]
Note: The cpufrequtils package is not available for CentOS (as of April 2009).
Links
Appendices
cpufreq-info
The CPU is an Intel E5200
cpufrequtils 005: cpufreq-info (C) Dominik Brodowski 2004-2006
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time: 0 1
hardware limits: 1.20 GHz - 2.50 GHz
available frequency steps: 2.50 GHz, 2.40 GHz, 2.00 GHz, 1.60 GHz, 1.20 GHz
available cpufreq governors: ondemand, powersave, userspace, performance
current policy: frequency should be within 1.20 GHz and 2.50 GHz.
The governor "userspace" may decide which speed to use
within this range.
current CPU frequency is 2.50 GHz (asserted by call to hardware).
cpufreq stats: 2.50 GHz:100.00%, 2.40 GHz:0.00%, 2.00 GHz:0.00%, 1.60 GHz:0.00%, 1.20 GHz:0.00%
analyzing CPU 1:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time: 0 1
hardware limits: 1.20 GHz - 2.50 GHz
available frequency steps: 2.50 GHz, 2.40 GHz, 2.00 GHz, 1.60 GHz, 1.20 GHz
available cpufreq governors: ondemand, powersave, userspace, performance
current policy: frequency should be within 1.20 GHz and 2.50 GHz.
The governor "userspace" may decide which speed to use
within this range.
current CPU frequency is 2.50 GHz (asserted by call to hardware).
cpufreq stats: 2.50 GHz:100.00%, 2.40 GHz:0.00%, 2.00 GHz:0.00%, 1.60 GHz:0.00%, 1.20 GHz:0.00%
yum install cpufrequtils
Dependencies Resolved ======================================================================================== Package Arch Version Repository Size ======================================================================================== Installing: cpufrequtils x86_64 005-1.fc10 fedora 39 k cpuspeed x86_64 1:1.5-2.fc10 updates 34 k
