- Troubleshooting Post-Installation Configuration Problems
- The sudo command
- First Update
- Configuring Software Repositories
- Installing Graphics Drivers
- Changing Ubuntu's Look and Feel
- Preferred Behaviors
- Input Devices
- Detecting and Configuring a Modem
- Configuring Power Management in Ubuntu
- Resetting the Date and Time
- Configuring and Using CD, DVD, and CD-RW Drives
- Configuring Wireless Networks
- Configuring Firestarter
- Reference
Configuring Power Management in Ubuntu
Advanced Configuration and Power Interface (ACPI) enables workstations and servers to automatically turn off when instructed to shut down. Most often used by Linux mobile users, ACPI can help extend battery sessions through the use of intelligent storage-cell circuitry, CPU throttling (similar to, but not the same as safety thermal throttling incorporated by Intel in Pentium III and IV CPUs), and control of displays and hard drives.
Most PCs support ACPI via the BIOS and hardware. ACPI support is configured, enabled, and then incorporated in the Linux kernel.
ACPI information is constantly available through the acpi command, which looks like this:
$ acpi -V Battery 1: charged, 100% Thermal 1: ok, 47.0 degrees C AC Adapter 1: on-line
This example provides information such as battery charge status, percentage of charge, as well as current system temperature and status of the AC adapter.
Alternatively, you can use the GUI tool that Ubuntu provides, which can be found under the System, Preferences menu as the Power Management option (shown in Figure 2.15).
Figure 2.15 Gnome Power Management allows you to monitor battery status and configure specific power-related actions, such as closing the lid of your laptop or pressing the power button.
Fortunately, Ubuntu provides good support for suspend and hibernate. Suspend means that your computer writes its current state to memory and goes into a low power mode, while Hibernate writes the current state of the system to disk and powers off the computer. Either way, your computer will start much faster the next time you go to use it.