[openbeos] Re: Hybernate and Resume functions

  • From: François Revol <revol@xxxxxxx>
  • To: openbeos@xxxxxxxxxxxxx
  • Date: Fri, 23 Apr 2004 14:45:47 +0200

Selon Brian Hague <BrianHague@xxxxxxxxxxxxxxxxxxxx>:

> Hello
> 
> I think it would also be a good idea to steal...
> 
> Wouldn't it be good if the entire RAM didn't need to be dumped onto the HDD
> (like my system) only what's used?
> What type of technologies are involved in the apple setup, or the x86?
> If the x86 is hardware based, is it proprietary from manufacturer to
> manufacturer?
> Is there any difference between Desktop hardware and Laptop hardware if it's
> a hardware issue?
> Is it totally software or does the memory and CPU get a trickle of power to
> hold the states?
> How much code would it require?  (realizing the R1+ factor)
> Could there be a shutdown memory dump? (completely bypassing any possible
> hardware issues)
> How would you do the resume on startup?
> Would you have a firstboot bug if the installer was saved into memory on
> shutdown?
> If you cleared the installer and there was no saved data would that also
> cause a bug?
> How can you make this work without torturing Axel and his basement "simpsons
> milk mice" any further?
> 

On x86, with APM, it's the BIOS which takes control to do that.
When there is a suspend request, an SMI (System Managment 
Interrupt) is generated, that stops the OS (which isn't very clean),
and saves the RAM.
I'm not sure how it's done for ACPI as the BIOS is supposed to be 
free of any task (the OS is supposed to know better when and what 
to do for pm stuff).
Btw, I remember seeing something that could do suspend-to-disk in 
Linux (kernel patch), without BIOS support. Check on freshmeat.net.

François.

Other related posts: