suspend2 merge (was Re: [Suspend2-devel] Re: CFS and suspend2: hang in atomic copy)

Pavel Machek
2007-04-24T20:23:50Z

Hi!

> > From subsequent emails, I think you already got your answer, but just
> > in case...
> >
> > Yes, if you enabled "Replace swsusp by default" and you already had it
> > set up for getting swsusp to resume. If not, and you're using an
> > initrd/ramfs, you'll need to modify it to echo
> > > /sys/power/suspend2/do_resume after /sys and /proc are mounted but
> > prior to mounting / and so on.
>
> yeah, went with the default suggested by your patch:
>
> CONFIG_SUSPEND2_REPLACE_SWSUSP=y
>
> and it was pretty easy to set things up. I used "echo disk >
> /sys/power/state" to trigger it.
>
> In hindsight it was all pretty straightforward and suspend2 worked
> beautifully on an UP and on an SMP system i tried. So in exchange for
> suspend2 folks debugging a bug in CFS here's some suspend2 review
> feedback ;) Any plans about moving suspend2 to the upstream kernel? It
> should be pretty easy for it to co-exist with the current swsuspend
> code.

Well, current uswsusp code can do most of stuff suspend2 can do, with
20% (or so) of kernel code.

"Major feature" that is missing is ability to save 100% of memory if
it is all the pagecache. I think that is not that important; we have
200 line patch to do that, but noone was able to verify it is correct.

Pavel
--
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