From owner-freebsd-current  Fri Aug 15 15:16:07 1997
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From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199708152215.RAA00969@dyson.iquest.net>
Subject: Minor word of warning about APM with WD DMA
To: current@freebsd.org
Date: Fri, 15 Aug 1997 17:15:53 -0500 (EST)
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Gang,
	This is just a heads-up, but it is a not-so-well known secret that I use
	IDE drives often (I am a cheap-skate.)  When going to work on-site at
	NCI/Navio/Oracle or whatever it is called today, I usually set my machine
	to run in powersaving mode.  Since the DMA changes (which I have enabled),
	my filesystems appear to be readily scrambled when APM is ON.  This is just
	a caveat, so that others might not get hosed by the problem.

	Not sure what is really going on here, so I am hesitating to lay-blame
	on mixing DMA and APM right now, and will not get a chance to look at
	it myself for a while.

	So, beware!!! :-).
	John