APM support for avoiding waking up laptops every few seconds?

Martin Pool (m.pool@pharos.com.au)
4 Aug 1997 00:02:01 -0000

> From: Greg Stark <gsstark@mit.edu>
> Date: 03 Aug 1997 03:52:02 -0400
> Subject: APM support for avoiding waking up laptops every few seconds?
>
> 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.

-- 
Martin Pool <m.pool@pharos.com.au>
Pharos Business Solutions