# &app; Help

2006-03-06
&apprelease;
Danny
Kukawka

    Danny.Kukawka@web.de

Thomas
Renninger

    trenn@suse.de

2005
Scott Rhoades

&app; is a utility used to set power consumption and conservation options.

KDE
KPowersave
power
battery
conservation
KPowersave

## Introduction

Use KPowersave, the KDE front-end to powersave, to control power management and monitor your laptop battery strength. For example, you can configure the screen on your laptop to turn off if the computer is not used for a specified amount of time, extending battery life.

### Starting KPowersave

To start KPowersave, open a shell and enter `kpowersave &` or select SystemDesktop Applet KPowersave from the GNOME or KDE menu. KPowersave opens in the system tray.

To configure whether KPowersave starts automatically when you log in, click General Settings then check or uncheck KPowersave starts automatically on login. Also specify whether you want KPowersave to ask you about starting automatically if you exit the application.

### Understanding the KPowersave Icon

The KPowersave icon looks like a power plug next to a battery strength indicator. The icon shows the current battery strength and whether the computer is powered by the battery or the power supply. When the battery power is low, the background of the icon flashes, orange for Warning and red for Low or Critical. If you leave the mouse cursor over the icon, a message shows whether the computer is plugged in or using the battery, the current charge level of the battery, and, if the computer is running on battery power, the approximate amount of time left before the battery power runs out.

## The systemtray applet menu

### Switch active scheme

To set the active scheme, right-click the KPowersave icon and select Set Active Scheme then select the scheme to use. If you change the active power management scheme with Set Active Scheme, all components of your system are part of the power saving effort. A power management scheme includes settings for CPU frequency scaling (if supported by your computer), throttling, hard disk control, and system cooling.

KPowersave menu with entries to switch schemes

### Starting the YaST Power Management Module

The YaST Power Management module (currently only available on SUSE) provides several settings designed to help conserve power. To start the module, right-click the KPowersave icon and click Start YaST2 Power Management Module. Detailed instructions for each setting are available in YaST.

KPowersave menu with entry to start YaST

Starting the YaST Power Management Module requires the root password.

### Suspending the System

You can suspend the system at any time by right-clicking the KPowersave icon and selecting Hibernate, Sleep, or Standby (if standby is supported by the computer).

- Hibernate saves all open data to disk before the computer is suspended. This protects your data if power is cut off or the battery dies.

- Sleep saves the data to RAM, making data retrieval faster when the computer is brought out of suspend mode.

- Standby deactivates the monitor while maintaining power to the system so that any open data remains in RAM.

The selections that are available depend on which methods have been activated in YaST by the administrator and whether standby is supported by your computer. The choice you make should depend on the likelihood of the computer losing power.

KPowersave menu with entries for suspend/standby

### Deactivating Autosuspend

If autosuspend is activated for the scheme currently used, Disable Actions on Inactivity appears in the KPowersave menu. If you select this option, any actions that are configured to take place when the computer is inactive do not happen, effectively deactivating autosuspend.

KPowersave menu with option "Disable Actions on Inactivity"

### Setting the CPU Frequency Policy

To control the amount of power used by the CPU by changing the CPU frequency policy, right-click the KPowersave icon, click Set CPU Frequency Policy, and choose one of the available options:

- Performance: Permanently keeps a high CPU frequency for maximum CPU performance.

- Dynamic: Reduces the CPU frequency when the system is idle and adjusts it dynamically if more CPU power is needed.

- Powersave: Maintains a low CPU frequency to save power.

The CPU frequency policy is only available in the menu if it is supported by your computer. If this option does not appear, it is not supported by your system.

KPowersave menu with submenu 'CPU Frequency Policy'

## Configuring a Power Management Scheme

### Understanding a Power Management Scheme

A scheme contains the basic power management configuration that is used when you use KPowersave with your computer. The number of available schemes depends on your Powersave configuration. Add or delete schemes with the YaST Power Management Module. Some common schemes include the following:

- Performance: Optimized for maximum performance during longer sessions

- Acoustic: Optimized to let the machine run as quietly as possible

- Presentation: Optimized for best performance when giving presentations

- Powersave: Optimized to conserve battery power

To choose a scheme, open the Scheme Settings tab, click the scheme to use, modify it as desired, then click OK.

KPowersave configure dialog (select schemes).

A scheme controls:

- Whether the screen saver is permitted to run when the computer is not in use

- How much time is allowed to pass before the screen goes into standby or suspend mode or is powered off

- Whether the computer automatically goes into Suspend mode after a specified amount of time

- Whether KPowersave should emit notifications

### Procedure to setup a scheme

All of these options conserve power by not allowing power-consuming processes to run. To configure scheme settings, do the following:

#### Screen Saver

1. Right-click the KPowersave icon in the sytem tray.

2. Select Configure KPowersave.

3. If the Scheme Settings tab is not already selected, click Scheme Settings.

4. Optionally, click Enable Specific Screensaver Settings.

   1. If you do not want the screen saver to consume power when the system is not in use, click Disable Screen Saver.

   2. To blank the screen instead of running a specific screen saver, click Only Blank the Screen. This option is not available if the screen saver is disabled.

#### Display Power Management

1. To manage the power consumed by the screen, click Enable Specific Display Power Management.

   Specific display power management (DPMS) can also be disabled by checking Disable Display Power Management. This setting overwrites the desktop configuration.

   1. Select the amount of time that should pass before the screen goes into standby mode. In standby mode, the screen is blanked, but continues to receive power. This provides a low level of power conservation.

   2. Specify the amount of time before the screen is suspended. In suspend mode, the screen is turned off but enough power is used to store the current screen information.

   3. Specify the amount of time that should pass before all power to the screen is turned off.

KPowersave configure dialog for screen saver and DPMS settings.

#### Setup Autosuspend

1. Click Autosuspend if you want KPowersave to suspend the system automatically if the current desktop user is inactive for a specified amount of time then use the dialog to configure specific autosuspend settings.

   For example, if you want the system to hibernate after 30 minutes, select the settings to do so. After 30 minutes, all open files are saved to disk and the computer is suspended.

KPowersave configure dialog for Autosuspend settings.

#### Setup Sound

1. To disable/reenable Notifications for the scheme click Miscellaneous. Change the Disable Notifications checkbox ti prevent emit Notifications. You can configure the notifications via the applet menu by select Configure Notifications....

## General Settings

### Locking the Screen

For improved security, you can lock the screen before the computer goes into suspend or standby mode or when you close the laptop lid. Lock the screen with a screensaver or with xlock.

To lock the screen, click the General Settings tab then select the settings to use.

KPowersave configure dialog for general settings.

### Creating an Autosuspend Blacklist

KPowersave provides an autosuspend blacklist. The blacklist prevents the system from being suspended if one of the listed applications is running. For example, you probably do not want your laptop to go into suspend mode while you are watching a DVD, just because you have not pressed a key for ten minutes. To edit the blacklist, click the General Settings tab then click Edit General Blacklist. Use the Autosuspend Blacklist Edit dialog to add or remove applications from your blacklist.

KPowersave configure dialog for Autosuspend Blacklist

You can also use this setting to create and edit blacklists for each scheme. When creating a scheme blacklist, you can import the general blacklist or create a specific blacklist for that scheme. A scheme-specific blacklist overrides the general blacklist when that scheme is in use.

KPowersave dialog to edit Blacklist