From owner-freebsd-hackers Wed Mar 4 11:24:42 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id LAA02681 for freebsd-hackers-outgoing; Wed, 4 Mar 1998 11:24:42 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from uni4nn.gn.iaf.nl (osmium.gn.iaf.nl [193.67.144.12]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id LAA02553 for ; Wed, 4 Mar 1998 11:24:24 -0800 (PST) (envelope-from wilko@yedi.iaf.nl) Received: by uni4nn.gn.iaf.nl with UUCP id AA20890 (5.67b/IDA-1.5 for hackers@FreeBSD.ORG); Wed, 4 Mar 1998 20:24:04 +0100 Received: (from wilko@localhost) by yedi.iaf.nl (8.8.7/8.6.12) id TAA01322; Wed, 4 Mar 1998 19:33:47 +0100 (MET) From: Wilko Bulte Message-Id: <199803041833.TAA01322@yedi.iaf.nl> Subject: Re: SCSI Bus redundancy... In-Reply-To: from Simon Shapiro at "Mar 3, 98 04:13:29 pm" To: shimon@simon-shapiro.org Date: Wed, 4 Mar 1998 19:33:47 +0100 (MET) Cc: grog@lemis.com, hackers@FreeBSD.ORG, blkirk@float.eli.net, jdn@acp.qiv.com, tlambert@primenet.com, sbabkin@dcn.att.com X-Organisation: Private FreeBSD site - Arnhem, The Netherlands X-Pgp-Info: PGP public key at 'finger wilko@freefall.freebsd.org' X-Mailer: ELM [version 2.4ME+ PL32 (25)] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG As Simon Shapiro wrote... > On 03-Mar-98 Wilko Bulte wrote: > > ... > > > The trick is cute, but it was used to park heads in the drives I saw. > > Not for flushing on drive caches. There would not be enough power to > > do e.g. a seek in order flush the cache. And by definition your platter > > rpm is dead wrong, you essentially use the whole thing as a > > electromagnetic brake. Not nice. > > I could swear the old Priam 14" had something like 0.5 sec before RPM will > degrad. And I am pretty sure it could flush all 2K of cache (2 seeks and > two rotations worst case with 1k sectors), but I could be wrong. 2K yes. Did you find any 2K RAMs the last time you looked in the catalog? ;-) > Most modern drives use the motor as an electromagnetic break. Try to snap > off the motor leads and you see the difference in spin-down time. I have > :-) I know. I've done my share of demolishing drives. Very enlightening, highly recommended to all these software-only techies that crowd the streets today :) _ ______________________________________________________________________ | / o / / _ Bulte email: wilko @ yedi.iaf.nl http://www.tcja.nl/~wilko |/|/ / / /( (_) Arnhem, The Netherlands - Do, or do not. There is no 'try' --------------- Support your local daemons: run [Free,Net,Open]BSD Unix -- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message