On CPU throttling

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Motivation

If the hardware is too muscular for the task, one can throttle the CPU to save energy and prevent overheating. This is referred to as {dynamic frequency scaling}.

Procedure

Modern computers usually already use dynamic frequency scaling in the sense that the frequency of the CPU is adjusted to the task load. This is accomplished through pre-defined management policies, for example one for when the computer is connected to the charger and one for when it's running on battery.

In addition to this smart power management, the user can further sacrifice performance for energy-efficiency and manually underclock the CPU.

On {debian}-based distributions, the CPU can be throttled with {tlp}—a power management tool for Linux. After installation, the configuration file at /etc/default/tlp can be modified for specific needs. The variable CPU_SCALING_MAX_FREQ_ON_[AC|BAT] controls the maximum frequency of the CPU for when the computer is connected to the charger and when it's operating on battery. Further, the variable ENERGY_PERF_POLICY_ON_[AC|BAT] determines how resourceful the CPU power is managed.

Monitoring

Information on the CPU can be viewed via:

    tlp-stat
  
Or, if installed:
    cpufreq-info
  

Last modified: Sun Jul 18 18:42:22 2021