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

[Chun-Yu Shei]

Steve Stavropoulos wrote:

>On Thu, 8 Jan 2004, Chun-Yu Shei wrote:
>
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>>Ari Pollak wrote:
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>>>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 :-\  
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>
> 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...)
>
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>>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.
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> If I had to guess I would say that in linux the hard disk drive never 
>spins down. Absolutely fixable...
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Yes, but I meant 4 hours in Windows without the HD spinning down also.  
I was talking more about stuff like ATI's PowerPlay that the Windows 
driver has that powers down the graphics card (by reducing its clock 
speed, iirc).

- Chun-Yu