Re: syncing the disks when entering sleep

Pavel Machek
2010-01-27T06:45:35Z

On Wed 2010-01-27 01:51:03, Rafael J. Wysocki wrote:
> On Tuesday 26 January 2010, Pavel Machek wrote:
> >
> > > > > > The ideal behavior would be:
> > > > > >
> > > > > > if(disk is spun up)
> > > > > > then let the sync happen
> > > > >
> > > > > I'm not against that. Patch welcome. :-)
> > > >
> > > > I'd say such knob would be ugly.
> > >
> > > Define "ugly", please.
> >
> > Per-system property, which should better be
> > per-program-that-requires-suspend. You request suspend without syncing
> > (you want it quick, battery is 90%), then the battery runs low, and
> > system daeomn requests s2ram, not realizing that someone disabled sync
> > from under him.
>
> I really prefer a per-system setting. The program that wants to sync anyway
> can easily do that by itself.

Well, existing programs expect existing behaviour... Programs that do
not want to sync can easily do it themselves, too, without afecting
rest of system.

> > > Nope.
> >
> > Nope what?
> >
> > AFAICT no new interface is needed. Just do SNAPSHOT_FREEZE, then
> > _S2RAM then _UNFREEZE.
>
> That's not quite straightforward and I wouldn't seriously suggest that to
> anyone.

Three ioctls, seems pretty much ok.
Pavel
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