JFS vs Fast file system, was Re: AIX vs standard unix

[Daniel Packman]

In response to my rather general praise of the journaled file system
under AIX (RS6000), a number of people have pointed out its lack of
reliability and the need to rebuild an entire file system.
In particular, Geoff Coleman writes:

>	And just hope you don't. On a couple of occasions I've had fsck 
>on our 6000 totally trash a file system. 
>
>	I'm still waiting for System V release 4 for the 6000.
>

I can only speak from personal experience and, unfortunately, can
only extend my sympathies for your travail.  Our experience here
(with some dozen or so RS6000's) is that the journaled file system
is rather robust.  Another advantage we see is the excellent memory
caching built into the io system.  With enough memory, we have found
operations such as unpacking a recently transferred set of files to
proceed with blinding speed.  Of course, sufficient memory is needed
to cache a set of files.

I certainly hope that whatever reliability problems exist get ironed
out before we stumble across them.

Dan Packman     NCAR                             INTERNET: pack at ncar.UCAR.EDU
(303) 497-1427  P.O. Box 3000                       CSNET: pack at ncar.CSNET
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