Re: [TuxOnIce-devel] [linux-pm] [SUSPECTED SPAM] Re: Proposal for a new algorithm for reading & writing a hibernation image.

Rafael J. Wysocki
2010-06-07T21:27:10Z

On Monday 07 June 2010, Martin Steigerwald wrote:
> Am Montag 07 Juni 2010 schrieb Nigel Cunningham:
> > Hi.
>
> Hi Nigel and Rafael, hi everyone else involved,
>
> > On 07/06/10 05:04, Rafael J. Wysocki wrote:
> > > On Sunday 06 June 2010, Maxim Levitsky wrote:
> > >> On Sun, 2010-06-06 at 15:57 +0200, Rafael J. Wysocki wrote:
> > >>> On Sunday 06 June 2010, Maxim Levitsky wrote:
> > > ...
> > >
> > >>> So how TuxOnIce helps here?
> > >>
> > >> Very simple.
> > >>
> > >> With swsusp, I can save 750MB (memory) + 250 Vram (vram)
> > >> With full memory save I can save (1750 MB of memory) + 250 MB of
> > >> vram....
> > >
> > > So what about being able to save 1600 MB total instead of the 2 GB
> > > (which is what we're talking about in case that's not clear)? Would
> > > it be _that_ _much_ worse?
> >
> > That all depends on what is in the 400MB you discard.
> >
> > The difference is "Just as if you'd never hibernated" vs something
> > closer to "Just as if you'd only just started up". We can't make
> > categorical statements because it really does depend upon what you
> > discard and what you want to do post-resume - that is, how useful the
> > memory you discard would have been. That's always going to vary from
> > case to case.
>
> Nigel and Rafael, how about just testing it?

ISTR that can be done to some extent using TuxOnIce as is, becuase there is a
knob that you can use to limit the image size.

> Whats needed to have 80% of the memory saved instead of 50%?
>
> I think its important to go the next steps towards a better snapshot in
> mainline kernel even when you do not agree on the complete end result yet.
>
> What about
>
> - Rafael, you review the async write patches of Nigel. If they are good,
> IMHO they should go in as soon as possible.

Yes, I'm going to do that.

> - Nigel and/or Rafael, you look at whats needed to save 80% instead of 50%
> of the memory and develop a patch for it

That would be my suggestion as well.

Thanks,
Rafael