29.6 The YaST Power Management Module
The YaST power management module can configure all power management
settings already described. When started from the YaST Control
Center with
, the first dialog of the module
opens (see Figure 29-1).
In this dialog, select the schemes to use for battery operation and AC
operation. To add or modify the schemes, click , which opens an overview of the existing schemes like that
shown in Figure 29-2.
In the scheme overview, select the scheme to modify then click
. To create a new scheme, click .
The dialog that opens is the same in both cases and is shown in
Figure 29-3.
First, enter a suitable name and description for the new or edited scheme.
Determine if and how the CPU performance should be controlled for this
scheme. Decide if and to what extent frequency scaling and throttling should
be used and whether processes with low priority (niced
processes) should be ignored when adjusting the CPU frequency. In the
following dialog for the hard disk, define a for maximum performance or for energy saving. The
controls the noise level of the hard disk
(supported by few hard disks). The
determines the cooling method to use. Unfortunately, this type of thermal
control is rarely supported by the BIOS. Read
/usr/share/doc/packages/powersave/powersave_manual.html#Thermal
to learn how you can use the fan and passive cooling methods.
Global power management settings can also be made from the initial dialog
using , ,
or . Access these controls by clicking
and selecting the appropriate item from the
menu. Click
to access the dialog for the battery charge level, shown in Figure 29-4.
The BIOS of your system notifies the operating system whenever the charge
level drops under certain configurable limits. In this dialog, define three
limits: , ,
and . 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 shutdown, because the remaining energy is not sufficient for continued
system operation. Select suitable charge levels and the desired actions then
click to return to the start dialog.
Access the dialog for configuring the ACPI buttons using . It is shown in Figure 29-5.
The settings for the ACPI
buttons determine how the system should respond to certain switches.
Configure the system response to pressing the power button, pressing the
sleep button, and closing the laptop lid. Click to
complete the configuration and return to the start dialog.
Click to enter a dialog in which to
determine if and how users of this system may use the suspend or standby
functionality. Click to return to the main dialog.
Click again to exit the module and confirm your power
management settings.