As gwr@netbsd.org wrote...
> > From: Jason Thorpe <thorpej@nas.nasa.gov>
> > Date: Tue, 09 Jun 1998 10:36:33 -0700
> [...]
> >  > I hasten to point out that I have a Quantum Fireball 1080S in this beast,
> >  > and this may be a HDA cache-flush issue; Apple had this problem with these
> >  > disks a few years ago. Is there an explicit SCSI command to force a disk to
> >  > flush its cache to permanent storage?
> > 
> > I think there is, but I can't remember for certain... this would be good
> > for a shutdownhook... each SCSI disk could register one, and ensure that
> > it has flushed its cache.
> 
> How about sending a SCSI "stop" command?  (i.e. spin down)

In general: flushing caches of disk drives is a dark and dangerous area.

I've discussed this with one of our diskdrive gurus and the consensus is
that you cannot really trust writeback caching on disks. Different f/w
revs on a single type of drive may give different results.

Wilko
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 |   / o / /  _  Bulte 				  email: wilko @ yedi.iaf.nl 
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