17.6. The YaST Power Management Module

The YaST Power Management module can configure all power management settings described above. When starting the module from the YaST Control Center (System->Power Management), the first dialog of the module is displayed (see Figure 17.1. “YaST Power Management: Scheme Selection”). In this dialog, select the schemes to use for battery operation and AC operation. To add or modify the schemes, click Edit Schemes, which opens an overview of the existing schemes like that shown in Figure 17.2. “YaST Power Management: Overview of Existing Schemes”.

Figure 17.1. YaST Power Management: Scheme Selection

YaST Power Management: Scheme Selection

Figure 17.2. YaST Power Management: Overview of Existing Schemes

YaST Power Management: Overview of Existing Schemes

In the scheme overview, select the scheme to modify then click Edit. To create a new scheme, click Add. The dialog that opens is the same in both cases (see Figure 17.3. “YaST Power Management: Adding a Scheme”).

Figure 17.3. YaST Power Management: Adding a Scheme

YaST Power Management: Adding a Scheme

First, enter a suitable name and description for the new or edited scheme. For the hard disk, define a Standby Policy for maximum performance or for energy saving. The Acoustic Policy controls the noise level of the hard disk. Click Next to enter the CPU and Cooling Policy dialog. CPU comprises the options CPU Frequency Scaling and Throttling. Use these options to define if and to what extent the CPU frequency may be throttled. The Cooling Policy determines the cooling method. Complete all settings for the scheme and click OK to return to the start dialog (Figure 17.1. “YaST Power Management: Scheme Selection”). In the start dialog, assign the custom scheme to one of the two operating modes. To activate your settings, exit this dialog with OK.

Global power management settings can also be made from the intial dialog using Battery Warnings or ACPI Settings. Click Battery Warnings to access the dialog for the battery charge level, shown in Figure 17.4. “YaST Power Management: Battery Charge Level”.

Figure 17.4. YaST Power Management: Battery Charge Level

YaST Power Management: Battery Charge Level

The BIOS of your system notifies the operating system whenever the charge level drops under certain configurable limits. In this dialog, define three limits: Warning Capacity, Low Capacity, and Critical Capacity. Specific actions are triggered when the charge level drops under these limits. Usually, the first two states merely trigger a notification to the user. The third critical level triggers a suspend, as the remaining energy is not sufficient for continued system operation. Select suitable charge levels and the respective actions then click OK to return to the start dialog.

Figure 17.5. YaST Power Management: ACPI Settings

YaST Power Management: ACPI Settings

Access the dialog for configuring the ACPI buttons using ACPI Settings. It is shown in Figure 17.5. “YaST Power Management: ACPI Settings”. The settings for the ACPI buttons determine how the system should respond to the actuation of certain switches. Configure the system response to pressing the power button, pressing the sleep button, and closing the laptop lid. Click OK to complete the configuration and return to the start dialog (Figure 17.1. “YaST Power Management: Scheme Selection”). Click OK again to exit the module and confirm your power management settings.