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Revision as of 00:59, 13 December 2004 by Wyrfel (Talk | contribs) (typos, added 2.4.23+ kernel note, changed number issued to proc-file to "5" as suggested by kernel docs)

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An often overlooked feature in 2.4.23+ and 2.6.6+ Linux kernels is the laptop-mode. It may be activated by writing a "5" into /proc/sys/vm/laptop_mode. Laptop-mode, when configured correctly, can make the kernel buffer disk activities for quite a long time and keep the harddisk spun down for most of the time to save power.

There is also a set of userland tools made to automatically manage all aspects of laptop-mode configuration according to the actual mode of operation (ac/battery-status). It is called laptop-mode-tools and you can install it in debian via apt-get or download it from here.

Almost anything you need to know about laptop-mode can be read in your Linux kernel documentation at /usr/src/linux/Documentation/laptop-mode.txt
If you can not find this file on your laptop, then go and get yourself the latest kernel sources.