[ltp] Hot Sleep

[Theodore Ts'o]

On Sun, May 02, 2004 at 03:51:08PM -0700, Crispin Cowan wrote:
> >yeah - acpi3 != supsend to ram
> >on my T40 either...
> > 
> >
> I'm not saying it doesn't work. It does work:
> 
>    * drive parks
>    * screen darkened
>    * power consumption way down

Power consumption is "lower" but it is definitely not completely
shutting down as much as if you were using APM.  Linux's ACPI power
management is just not up to snuff right now, unfortunately.  

> So I intend to keep using it. I was just wondering if I'm doing 
> something wrong such that a hot component is staying powered up.

Yes, you're using ACPI; that's your mistake.  :-)

> It sounds like it is just that ACPI is not mature enough to power down 
> everything in suspend-to-RAM.

Correct.

> >i switched back to apm
> > 
> I'm confused by this recommendation. I don't have any APM stuff 
> installed, and I thought APM was unavailable in newer hardware. How do I 
> switch "back" to APM? I.e. how do I enable it for this OS (Linux 2.6.4) 
> and hardware (T40).

Either disable ACPI (and enable APM) in your kernel build options, or
just enable both ACPI and API when you build your kernel, and then
disable ACPI at boot time by adding "acpi=off" in your kernel
command-line options, in either your lilo.conf or /boot/grub/menu.lst
file.

						- Ted