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From: Joe Greco <jgreco@brasil.moneng.mei.com>
Message-Id: <199608291429.JAA06769@brasil.moneng.mei.com>
Subject: Re: [Q]: formula for calculating BPI needed
To: jmb@freefall.freebsd.org (Jonathan M. Bresler)
Date: Thu, 29 Aug 1996 09:29:26 -0500 (CDT)
Cc: moos@degnet.baynet.de, questions@FreeBSD.ORG, freebsd-hackers@FreeBSD.ORG
In-Reply-To: <199608290016.RAA15559@freefall.freebsd.org> from "Jonathan M. Bresler" at Aug 28, 96 05:16:52 pm
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> > since the capacity of a 295 feet-DAT-tape is about 2 GB.
> > After scanning the sources of dump for the estmated-tapes-formula,
> > i found some strange constants being used there that i do not
> > understand and that are not documented nor explained anywhere.
> > I want to rewrite the formula for this calculation in
> > the dump-sources but i need some informations on this topic.
> 
> 	no, you dont ;)  well maybe you do but others dont want you to :)
> 	the formulas in dump are there for the old 9-track tapes.
> 	just use the newer parameters: B and b.

Modifying the manual page to include a description along these lines might
be a much better utilization of time...  modifying the formulas is silly
because it will fail when we move on to another major type of tape
technology.  Jonathan's suggestion to use B and b is probably right on.

... JG