[ltp] Thinkpad buttons, /dev/nvram, and return from S3 with ACPI

[Steve Stavropoulos]

On Thu, 8 Jan 2004, Chun-Yu Shei wrote:

> Ari Pollak wrote:
> 
> > I never really tried APM on this laptop so I don't know how well it 
> > works; I suppose I should, the battery life when using ACPI & cpudynd 
> > isn't that great anyway (about 2 1/2 hours with the standard battery).
> 
> Heh, now this is a huge reason to run Windows :)  I can get 4 hours in 
> Windows if I keep my CPU usage down, but in Linux with it fixed at 600 
> MHz, I still can barely get 2 1/2 hours (with the 6 cell, not 9 cell 
> battery).  Power management in Windows is far better than in Linux :-\  

 I don't aggree with that. Maybe it's easier in windows, but definetely 
not better. In Linux it's a little harder and the current apm scripts in 
most distros are _stupid_. For example in fedora core 1 you get nice 
laptop_mode enabled when in battery so the kernel waits longer before it 
flushes its buffers, giving the hard drive time to spin down. BUT, the 
bdflush isn't changed accordinally, so you have ext3 writing in disk every 
6 seconds and the disk never spins down. In windows probably you wouldn't 
experience this problem, but you wouldn't get the bdflush option either :>
 Also in windows you can't play divx videos with the cpu running at 200MHz 
or even less (if only intel would let us set the frequency below 
600MHz...)

> Looking at the power usage ACPI provides, it looks like in Linux it 
> never goes under 11-13W or so (if I remember correctly...APM only now).  
> In Windows it can go down as low as 8-10W.
> 

 If I had to guess I would say that in linux the hard disk drive never 
spins down. Absolutely fixable...