From owner-freebsd-chat Sat Nov 23 13:36:34 1996 Return-Path: owner-chat Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id NAA14648 for chat-outgoing; Sat, 23 Nov 1996 13:36:34 -0800 (PST) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id NAA14637 for ; Sat, 23 Nov 1996 13:36:26 -0800 (PST) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id OAA19464; Sat, 23 Nov 1996 14:21:52 -0700 From: Terry Lambert Message-Id: <199611232121.OAA19464@phaeton.artisoft.com> Subject: Re: ATAPI (was: Who needs Perl? We do!) To: joelh@gnu.ai.mit.edu (Joel Ray Holveck) Date: Sat, 23 Nov 1996 14:21:52 -0700 (MST) Cc: grog@lemis.de, terry@lambert.org, chat@FreeBSD.org In-Reply-To: <199611231856.NAA03954@hill.gnu.ai.mit.edu> from "Joel Ray Holveck" at Nov 23, 96 01:56:27 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-chat@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk > What are these A/V drives I see nowdays? Are these just > standard-issue SCSI drives trying to get on the 'multimedia' > bandwagon, or is there really something else to them? They are standard drives which do not have an off cycl;e for thermal recalibration. This makes them faster to dump an incoming stream of "A/V" data and turn around for more data, but it makes them much more sensitive to thermal variance. If you have a machine you leave on all the time, and you scsiformat after it has reached thermal equilibrium, and never remount after a crash until it is, again, at thermal equilibrium, and you maintain a standard thermal profile with consistent ventilation to a controlled environment in which the machine is placed, you can use them all day with no difference, except they are slightly faster over a bursty short haul. If you don't do any of these things, they are slightly faster over a bursty short haul, but they have a *significantly* decreased MTBF. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.