Re: APM support for avoiding waking up laptops every few seconds?

Pavel Machek (
Mon, 4 Aug 1997 11:14:49 +0200


> > It would be nice if the laptop feature to spin down the drive weren't
> > nearly completely defeated by Unix's intelligent memory management. I
> > know people have suggested (and implemented) disabling updating atime
> > as a solution, but i think that would only help a little. Really, all
> > disk activity should be avoided and delayed whenever the disk is spun
> > down.
> >
> > Ideally what i would like to see would be,
> >
> > 1 Just before the APM spins down the disk, a sync should be done.
> > Though i'm not actually sure there's any way to request such
> > notice.
> I think recent versions of apmd arrange for a callback from the BIOS
> before the machine suspends, and take advantage of this to sync. I'm
> still trying to get this set up properly.
> There is room for improvement wrt avoiding writes if the disk is spun
> down.

I have modified bdflush to do exactly following, it needs _NOT_ to
know about apm, it does need to patch kernel.

Mail me.

I'm really 	   Pavel
Look at ;-).