[TriLUG] Laptop Linux

[Mike Mueller]

Found some notes about Linux on Laptops that rang true to my experience.  
Under XP I am getting nearly a full day of usage (off and on) on a single 
battery charge.  On my Presario running Linux with no ACPI control I got 45 
mn.  With Linux I've read that ACPI control is incomplete and that HD control 
is done with a separate program.

Anybody have measurements on how long a battery charge lasts using Linux on a 
laptop?

What I conclude from reading this is that Linux control of ACPI ... well ... 
er ... sucks right now.  I'll continue to research this, but if anyone has 
information to the contrary I'd like to see it.

Excerpts from http://www.freelabs.com/~whitis/linux/xf335/ below:

Notes on Resizing XP partition

There are no free tools to resize an NTFS partion. There are several 
commercial programs which can do that. I chose instead to delete the 
partition, recreate it as a smaller FAT32 partition, make it primary, format 
it, and run the HP reinstall in "Restore C: only" mode. Note that the HP 
reinstall will trash any linux partion at hda2 - you need to make windows 
partition 2. Of course, the best thing is to delete eXtra Pain entirely.

MM: I was following up a suggestion to use Knoppix and one of the OSS 
partition resizers.  The information above seems to be correct given what is 
written at www.ranish.net/part. Support for NTFS in OSS and shareware is 
experimental or embryonic.

Battery Life

Battery life is very poor at the moment, about 1-1/4 hours. This is because 
we don't have control over many of the power management features. The screen 
backlight is at high intensity all the time; close the lid to conserve power.

ACPI

ACPI stands for Advanced Configuratin and Power Interface Specification. New 
computers do not have a traditional BIOS which allows you to configure the 
machine. Instead, the ACPI bios gives the operating system control over the 
machine configuration. About all the user has control over is the boot order 
and even then we still don't have a decent boot loader in the bios. Another 
acronym used is OSPM, or Operating System Power Management; this is code in 
the operating system which communicates with the ACPI bios through the ACPI 
Driver/AML Interpretter. ASL, which stands for ACPI Source Language, is 
compiled into AML, which stands for ACPI Machine Language. DSDT stand for 
Differentiaded System Description Table which is basically a table describing 
the system configuration.

Linux support of ACPI is pretty sketchy at the moment.

ACPI support under windoze is pretty sketchy too. Basic stuff like battery 
monitoring works but if you want to configure your EPP/ECP parallel port into 
EPP mode instead of ECP, you are out of luck.

-- 
Mike Mueller
324881 (08/20/2003)
Make clockwise circles with your right foot. 
Now use your right hand to draw the number "6" in the air.