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CPUPOWER-IDLE-SET(1)                               cpupower Manual                               CPUPOWER-IDLE-SET(1)



NAME
       cpupower idle-set - Utility to set cpu idle state specific kernel options

SYNTAX
       cpupower [ -c cpulist ] idle-info [options]

DESCRIPTION
       The cpupower idle-set subcommand allows to set cpu idle, also called cpu sleep state, specific options offered
       by the kernel. One example is disabling sleep states. This can be handy for power vs performance tuning.

OPTIONS
       -d --disable <STATE_NO>
              Disable a specific processor sleep state.

       -e --enable <STATE_NO>
              Enable a specific processor sleep state.

       -D --disable-by-latency <LATENCY>
              Disable all idle states with a equal or higher latency than <LATENCY>.

              Enable all idle states with a latency lower than <LATENCY>.

       -E --enable-all
              Enable all idle states if not enabled already.


REMARKS
       Cpuidle Governors Policy on Disabling Sleep States

           Depending on the used  cpuidle governor, implementing the kernel policy how to choose sleep states, subse‐
           quent sleep states on this core, might get disabled as well.

           There  are  two  cpuidle governors ladder and menu. While the ladder governor is always available, if CON‐
           FIG_CPU_IDLE is selected, the menu governor additionally requires CONFIG_NO_HZ.

           The behavior and the effect of the disable variable depends on the implementation of a  particular  gover‐
           nor. In the ladder governor, for example, it is not coherent, i.e. if one is disabling a light state, then
           all deeper states are disabled as well. Likewise, if one enables a deep state but a lighter state still is
           disabled, then this has no effect.

       Disabling the Lightest Sleep State may not have any Affect

           If criteria are not met to enter deeper sleep states and the lightest sleep state is chosen when idle, the
           kernel may still enter this sleep state, irrespective of whether it is  disabled  or  not.  This  is  also
           reflected in the usage count of the disabled sleep state when using the cpupower idle-info command.

       Selecting specific CPU Cores

           By default processor sleep states of all CPU cores are set. Please refer to the cpupower(1) manpage in the
           --cpu option section how to disable C-states of specific cores.

FILES
       /sys/devices/system/cpu/cpu*/cpuidle/state*
       /sys/devices/system/cpu/cpuidle/*

AUTHORS