RFS loopback performance (was Re: uid-mapping ...)

[David Dawes]

In article <1991Mar05.183924.15581 at chinet.chi.il.us> les at 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 at suphys.physics.su.oz.au) DoD#210   | Phone: +612 692 2639
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