Laptop Mode Tools is a laptop power saving package for Linux systems. It allows you to extend the battery life of your laptop, in several ways.
It is the primary way to enable the Laptop Mode feature of the Linux kernel, which lets your hard drive spin down. In addition, it allows you to tweak a number of other power-related settings using a simple configuration file.
Laptop mode is a kernel "mode" that allows you to extend the battery life of your laptop. It does this by making disk write activity "bursty", so that only reads of uncached data result in a disk spinup. It causes a significant improvement in battery life (for usage patterns that allow it).
The initial version, written by Jens Axboe, appeared in Linux 2.4.23. A port by Bart Samwel has been included in kernels starting from 2.6.6. This page was originally written by Bart Samwel to host his 2.6 port; as the port has been merged a long time ago, the current page only serves as a placeholder.
Please mail/CC bug reports and feature requests to me directly. If you post them on the linux kernel mailing list I will probably not see them.
Linux Journal Article.
The September 2004 issue of Linux Journal contains an article on Laptop Mode (written by me). I'll take this opportunity to point out a number of changes that have taken place since the article was written.
- Setting it up: the whole setup process has been simplified by the introduction of laptop mode tools. Installing them is all you need to do to get laptop mode up and running. If you're running acpid or pbbuttonsd, laptop mode tools will automatically start when your laptop goes into battery mode. In addition, the laptop mode tools package will automatically manage your hard drive's idle timeout and power management settings (if you've configured it properly, of course), so you don't have to worry about manually invoking hdparm anymore.
- Configuration: the article mentions configuration settings in /sbin/laptop_mode. First of all, laptop mode tools installs the script in /usr/sbin/laptop_mode. Second, the configuration has been moved to a separate file, /etc/laptop-mode/laptop-mode.conf. The laptop mode tools package contains a full description of all the available configuration settings in the manual page laptop-mode.conf(8).
These are links to Laptop Mode Tools packages and/or installation instructions for the following distributions:
If your distribution is not in this list, you can try the .tar.gz version.
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