# CPU Frequency Scaling Monitor Manual

## Introduction

### CPU Frequency Scaling Monitor

The CPU Frequency Scaling Monitor provides a convenient way to monitor the CPU Frequency Scaling for each CPU.

To add CPU Frequency Scaling Monitor to a panel, right-click on the panel to open the panel popup menu, then choose Add to Panel CPU Frequency Scaling Monitor.

Unfortunately, CPU frequency scaling can currently only be monitored on Linux machines that have support in the kernel. It can however, support the several generations of frequency scaling interfaces in the kernel.

When there is no CPU frequency scaling support in the system, the CPU Frequency Scaling Monitor only displays the current CPU frequency.

When CPU frequency scaling is supported in the system, the CPU Frequency Scaling Monitor displays the CPU icon with a progress bar. The state of the progress bar represents the current CPU frequency with respect to the maximum frequency.

By default the CPU Frequency Scaling Monitor displays the current CPU frequency as a value in Hertz (the standard measure of frequency), but can be configured to display a percentage instead. For more information on how to configure CPU Frequency Scaling Monitor see cpufreq-applet-prefs.

Each instance of CPU Frequency Scaling Monitor can monitor only one CPU. You must start an instance of CPU Frequency Scaling Monitor for each CPU that you want to monitor if you are in a multiprocessor (SMP) system.

### Understanding the Icons

The CPU Frequency Scaling Monitor has a series of icons that graphically represent the current scaling level of the processor you are monitoring. They are:

Icon | Description
100% Power | The CPU is running at, or close to, 100% throughput
75% Power | The CPU is running at, or close to, 75% throughput
50% Power | The CPU is running at, or close to, 50% throughput
25% Power | The CPU is running at, or close to, 25% throughput

### Frequency and Governor Selector

The Frequency Selector functionality may not be available on your GNOME Desktop by default. Please consult your system administrator, vendor documentation or the documentation that came with this software.

To set the CPU frequency, left click on the monitor and a menu will be shown. This menu will offer you a list of available frequencies and/or frequency governors for your machine.

You can choose whether you want to show available frequencies or governors in the Preferences. See cpufreq-applet-prefs for more information.

#### Frequency selector showing just frequencies

#### Frequency selector showing both frequencies and governors

## Preferences

To configure the CPU Frequency Scaling Monitor, right-click on the applet, then choose Preferences from the popup menu.

The Preferences dialogue contains the following components:

### CPU Frequency Scaling Monitor Preferences Dialogue

CPU Frequency Scaling Monitor preferences dialogue

Monitored CPU (only in multiprocessor systems)

- Use this drop-down list to select the CPU that you want to monitor.

  ### Selecting the CPU to monitor

  CPU Frequency Scaling Monitor preferences dialog CPU selector

  The Monitored CPU option will only appear on multiprocessor (SMP) systems.

Show in Mode

- Use this drop-down list to select the mode in which you want to display the applet. Available modes are: Graphic, Text and both (Graphic and Text)

Show CPU frequency as frequency

- Select this option to display the current CPU frequency.

Show frequency units

- Select this option to display or not the frequency units in the frequency mode.

Show CPU frequency as percentage

- Select this option to display the current CPU frequency as a percentage.

Show menu

- This option allows you to choose how much information is shown in the frequency selector dropdown (see gnome-cpufreq-selector). You can select to display Frequencies, Governors or both Frequencies and Governors.

  ### The selector configured to Frequencies and Governors

  CPU governors selector