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From: dawes@suphys.physics.su.OZ.AU (David Dawes)
Newsgroups: comp.unix.sysv386
Subject: RFS loopback performance (was Re: uid-mapping ...)
Message-ID: <1991Mar6.142215.22193@metro.ucc.su.OZ.AU>
Date: 6 Mar 91 14:22:15 GMT
References: <1991Mar2.155055.304@unixland.uucp> <1991Mar05.183924.15581@chinet.chi.il.us>
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Reply-To: dawes@suphys.physics.su.OZ.AU (David Dawes)
Organization: School of Physics, Uni of Sydney, Australia.
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In article <1991Mar05.183924.15581@chinet.chi.il.us> les@chinet.chi.il.us (Leslie Mikesell) writes:
>
>BTW, I've considered setting up a loop-back mount just to be able to
>get a read-only mount so I could do a backup without touching the
>atime or ctime of the files, but I've been too lazy to try it.  What
>kind of performance do you get?

I did a test, just reading a 12MB file both from the physical mount point,
and the loopback mount point:

            sys        real
direct      13s        37s
rfs         22s        76s

(My system is Esix Rev.D, 25MHz 386DX, 100MB Conner IDE disk, ffs filesystems)

I decided to try rfs loopback so I could get something like sym-links
across filesystems.

David
--
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 David Dawes (dawes@suphys.physics.su.oz.au) DoD#210   | Phone: +612 692 2639
 School of Physics, University of Sydney, Australia    | Fax:   +612 660 2903
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