Re: [PATCH 1/8] PM: Opportunistic suspend support.

Pavel Machek
2010-05-26T17:28:35Z

On Wed 2010-05-26 12:14:02, James Bottomley wrote:
> On Wed, 2010-05-26 at 19:00 +0200, Peter Zijlstra wrote:
> > On Wed, 2010-05-26 at 11:54 -0500, James Bottomley wrote:
> > > Given that I'm in the latter category, I think suspend blockers is a
> > > reasonable solution to an existing problem. I like Alan's idea of
> > > restricting the API into a single user space program so we contain the
> > > API contamination ... but realistically that's mostly the current
> > > suspend blockers anyway.
> >
> > There's a _large_ difference between resource limits and these wonky
> > suspend blockers.
>
> Well, you have policy and then you have implementation ... suspend
> blockers just looks like an implementation to me. It seems to be
> reasonably well suited in that regard ... after all, we kill processes
> that exhaust memory for instance or cut off write privileges to those
> that go over quota. Preventing power hungry processes from consuming
> power by not allowing them to run until there's a wakeup event is fairly
> gentle by those standards.

Well, generic mechanism would stop processes when they run over
something -- not arbitrarily link it to device wakeup.

> > The main and most important one being that suspend is a global property
> > and can/will hurt sensible tasks. It puts the whole task model upside
> > down.
>
> OK, so I believe you have an android phone ... it already implements
> this model ... specifically what are the problems on that platform this
> causes?

Besides that it is not linux system at all?

Yes, with custom userspace it works extremely nicely.

Had anyone even tried running oportunistic suspend on normal desktop?
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html