new power management implementation

Felipe Figueiredo philsf79 at
Fri Dec 5 12:03:45 UTC 2008

On Thursday 04 December 2008 15:07:14 Odysseus Flappington wrote:
> 2008/12/4 (``-_-ยดยด) -- Fernando <ubuntu at>

> I'm not sure what you mean by s2both.
> I'm talking about the Use Case in the spec that says: "A user puts the
> computer to sleep on battery, but then forgets about it. The computer
> should then go into a deeper power save state like hibernate."
> Essentially the plan is to replace Suspend and Hibernate with one 'Sleep'
> mode which initially suspends. Then after a certain amount of time of
> suspending without being turned on again, it hibernates to save even more
> power.

This is called hybrid suspend but the usual linux scripts, also called suspend 
+ hibernate by some. The 's2both' Fernando mentioned is one implementation of 
the concept (as in s2ram + s2disk). Ubuntu dropped support for these 
framework in favor of pm-utils, which also support this feature.

Unfortunately, the BIOS of the computer must support it (mine doesn't, for 
example, a Lenovo 3000 v100). It also seems it's fairly common to find buggy 
ACPI implementations in laptop BIOSes, which is one of the reasons why 
suspend/hibernate in linux is so inconsistent nowadays. 

It's not only a matter of Ubuntu including support for it, your hardware must 
support it too. Also, Ubuntu should find out how to deal with specific 
hardware model quirks, just as it happens with suspend and hibernate. I think 
this kind of feature is importante enough that it's already in the radar of 
some (most?) developers who are laptop users, although I don't know who or if 
someone is actively working on it. 

Also, as I said, pm-utils already implements it, so you should test it from 
the command line (gnome-power-manager doens't include it in the GUI, AFAICT) 
and see if it works.

Maybe a BIOS update from the manufacturer can include this, if it doesn't 
support hybrid yet.


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