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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Jeremy Maitin-Shepard <jbms@cmu.edu>
Subject: Re: Hibernation considerations
Date: Tue, 17 Jul 2007 22:58:33 +0200
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On Tuesday, 17 July 2007 22:39, Jeremy Maitin-Shepard wrote:
> david@lang.hm writes:
> 
> [snip]
> 
> > the non-ACPI hibernate behaves very differently, and for some people (and I
> > think I am one of them) it will meet their needs better then _any_ of the ACPI
> > suspends.
> 
> It may have certain differences from the user point of view, but from
> the implementation view, it seems that it is nearly exactly the same.
> The only differences seem to be: 
> 
>  - rather than shutting down, do whatever is necessary to stick the
>    system in S4 state.
> 
>  - make sure ACPI isn't initialized by the "load image" kernel
> 
>  - rather than "resume from hibernate" ACPI by initializing it normally,
>    issue the special hibernate-related methods.
> 
> Thus, it seems that supporting ACPI S4 will have a very minimal affect
> on the hibernate implementation.

Still, you need to take it into account.

Greetings,
Rafael


-- 
"Premature optimization is the root of all evil." - Donald Knuth