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Battery Powered Linux Mini-HOWTO

David Lechnyr

Revision History
Revision 2.312003-07-30Revised by: drl
Minor updates
Revision 2.02002-10-08Revised by: drl
Major updates and conversion to SGML
Revision 1.01997-12-21Revised by: hm
Initial draft by Hanno Muller

This document describes how to optimize and configure power management on a ready-configured Linux system for use on battery-powered laptops. This will be helpful for everyone who runs Linux on a portable computer system. APM/ACPI methods of power management are discussed along with power saving tips and techniques. There is also some discussion about the different types of batteries available.

Table of Contents
1. Power Management
1.1. Advanced Power Management (APM)
1.2. Advanced Configuration and Power Interface (ACPI)
1.3. APM vs. ACPI: Which one?
1.4. SMP, Hyper-Threading, IA64 & NUMA
2.1. Normal
2.2. Standby
2.3. Suspend
2.4. Off
3. Power Management Methods
3.1. swsusp(8)
3.2. hdparm(8)
3.3. sysklogd(8)
3.4. XFree86
3.5. KDE 3.1
3.6. Energy Star
3.7. Swap File
3.8. tmpfs
3.9. Miscellaneous Tuning
3.10. Power Saving Myths
4. Types of Batteries
4.1. Nickel Cadmium (Ni-Cd)
4.2. Nickel Metal Hydride (Ni-MH)
4.3. Lithium Ion (Li-ion)
4.4. Smart Batteries
4.5. General Battery Care
5. Appendix