Re: Hibernation considerations

[Rafael J. Wysocki]

On Tuesday, 17 July 2007 23:06, david@xxxxxxx wrote:
> On Tue, 17 Jul 2007, Jeremy Maitin-Shepard wrote:
> 
> > david@xxxxxxx writes:
> >
> > [snip]
> >
> >>>> * figure out which devices can wake up
> >>>> * put devices into low power states (wake-up devices are placed in the Dx
> >>>> states compatible with the wake capability, the others are powered off)
> >
> >> this can't be done by the image-saving kernel if that kernel doesn't know about
> >> the device.
> >
> > The image-saving kernel can be made to know about all of the "wake up"
> > devices; all other devices should have already been powered off by the
> > "hibernated" kernel.
> 
> not nessasarily.

More than that.  The hibernated kernel should not power off any devices,
because that is _wasteful_ (unless, of course, the powering off a device is the
only way to quiesce it).

Greetings,
Rafael


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