From owner-freebsd-geom@FreeBSD.ORG  Tue Jun 15 05:38:45 2004
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To: Gordon Tetlow <gordon@freebsd.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 14 Jun 2004 15:09:31 PDT."
             <20040614220931.GR10016@spiff.melthusia.org> 
Date: Tue, 15 Jun 2004 07:38:42 +0200
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cc: geom@freebsd.org
Subject: Re: GEOM class idea... 
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In message <20040614220931.GR10016@spiff.melthusia.org>, Gordon Tetlow writes:

>> Many of us read CD's into iso images, stick them on a harddisk and
>> mount them from there when we need to access them.  This usually
>> costs us a md(4) vnode gadget, and that is really a waste.
>
>=2E.. description of grotty geom class ...
>
>I can't imagine that all the pain that you are talking about is a
>worthwhile effort when it's so easy to do a md backed file. I can
>just about guarentee that users will have spare files and capacity
>before they have a spare disk running around.
>
>Maybe I'm missing something here, but what is the advantage of
>going straight off of the disk? Are you trying to avoid the FFS
>filesystem overhead?

You would save both the md and ffs overhead and gain about 10% disk
capacity in the process.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.