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From: dave@lethe.UUCP (Dave Collier-Brown)
Newsgroups: comp.os.research
Subject: Re: References for Fault Tolerent, "safe" file system
Message-ID: <7034@saturn.ucsc.edu>
Date: 6 May 89 00:22:23 GMT
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In article <7013@saturn.ucsc.edu> vlohia@orville.nas.nasa.gov (Ved P. Lohia) writes:
>I am looking for references regarding fault tolerent, "safe" file system.
>Our group is developing Mass Storage Subsystem. We need to meet following
>goals related to file system.
> 
>1. Single failure of "media hardware or software" shold not cause a
>   irrecoverable loss of data.
>
>2. Better recovery techniques shold be provided (FSCK is far too slow on
>   a "standard" sized file system, it will be impossible for an MSS sized
>   file system.
>
>Pointers from netters will be much appreciated.
>vlohia@navier.nas.nasa.gov 

  The subject isn't new, but a fair bit of work has been done on it.  One of
the better papers was by Ian Davis (then of ICL) at the University of Toronto.
This was distantly related to their Unix-like TUNIS operating system project.

  Davis, Ian John, "Towards Reliable File Systems", Masters thesis, date
unknown. 91pps, refs.

Abstract:
	The purpose of this thesis is to investigate the potential
damage caused to file systems by system failures, and to present ways of
improving the tolerance of file systems to such failures. It will be
shown that many of the problems associated with systems failures can be
avoided if certain facilities can be made available, and these are used
wisely by the system designer. These facilities will allow the designer
to ensure that following system failure the files held on the disc are
in a valid state, and thus continue to be usable. In addition, some
causes of system failure will be detected by the file system, and
corrected automatically. These include the detection of suspect storage
areas, and data overflow when storage devices become full. We will be
concerned primarily with UNIX type file structures, but hope that any
conclusions drawn will be applicable to other systems. It is considered
of some importance that the methods proposed do not unduly degrade
machine performance.

  Ian was a colleague many years ago, and was rather subtle. I was
suitably impressed with his verbal descriptions and extracted a
(lineprinter) copy of his thesis.

--dave (who wonders where he went) c-b

-- 
David Collier-Brown,  | {toronto area...}lethe!dave
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