From owner-freebsd-mobile  Tue Mar 13  1:38:44 2001
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From: Soren Schmidt <sos@freebsd.dk>
Message-Id: <200103130938.KAA95619@freebsd.dk>
Subject: Re: Disk I/O problem in 4.3-BETA
In-Reply-To: <20010313013301.L29888@fw.wintelcom.net> from Alfred Perlstein at "Mar 13, 2001 01:33:01 am"
To: bright@wintelcom.net (Alfred Perlstein)
Date: Tue, 13 Mar 2001 10:38:30 +0100 (CET)
Cc: mwm@mired.org (Mike Meyer),
	Helge.Oldach@de.origin-it.com (Helge Oldach), oberman@es.net,
	mobile@FreeBSD.ORG, stable@FreeBSD.ORG
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It seems Alfred Perlstein wrote:
> 
> Having write caching on is like having the disk ignore _any_
> filesystem's attempt to do softupdates/logging/delayed-order-writes
> because the disk _lies_ to the OS about when a write is safely on
> the disk.

Hmm, I think the problem here is that the OS doesn't tell the
drivers WHEN it expects to have data written to disk, I can't
see why it should not be possible to have even softupdates
say "now before I write this I expect everything so far to 
be on disk".

-Søren

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