Subject: Re: 1.4.1, APM, SCSI disk spin down how?
To: Hal Murray <murray@pa.dec.com>
From: Eric Haszlakiewicz <erh@nimenees.com>
List: current-users
Date: 07/26/2000 23:52:33
On Wed, Jul 26, 2000 at 06:03:18PM -0700, Hal Murray wrote:
> This is an area I don't understand.  Why does a disk that isn't doing 
> anything need to get written to every 30 seconds?  I assume it's 
> only updating the time-last-running.   Is there something fundamental 
> going on that I don't know about?  If so what?
	It shouldn't.  In current versions of NetBSD update shouldn't
be running so you shouldn't have the 30-second re-sync.  The update
program has been superceeded by in-kernel trickle sync.
	However, you might need to set noatime and/or nodevmtime
when mounting file systems to avoid writing to the disk when an application
is actually only reading.  Perhaps a variation of this that merely saved
the access time and any other implied write until something wrote some
actual data to the disk.  (it doesn't do something like this yet, does it?)

eric