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Originally published in Queue vol. 2, no. 8
see this item in the ACM Digital Library



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(newest first)

Mikael Sitruk | Wed, 20 Oct 2010 09:08:06 UTC

Great article. Totally agree that we should design our softwares with failure handling in mind.

John Benson | Fri, 16 Oct 2009 06:25:16 UTC

Very nice Cook's tour of the field.

I'm feeling a little cantankerous, however, because a lot of the problems discussed were encountered and satisfactorily solved for the mainframe world by Tandem Computers during the late seventies and early eighties. I remember conversations back then about dual-ported controllers, RAID-0, fail-fast, NonStop process pairs, degrees of transaction isolation and split-brain syndrome in the Tandem system of loosely-coupled processors, many years before some of them became general IT currency.

Most of the last twenty-five years I've had to watch people cobble together inferior solutions from networked micros in apparently complete ignorance of that prior art. Not that it matters much for serving static webpages, but banks and stock exchanges are pretty picky about database integrity, transaction processing and rapid as well as exact recovery of a consistent state whether you lose a processor or a whole site.

I would bet that Mr. Lindsay knows something about the Tandem, whose database design owes much to Berkeley Computer Sci RDBMS research. I just wish that the 15 or so Tandem designers would get more credit for implementing a lot of what still passes for forward thinking into a commercially-available system a quarter-century ago.

Also, thanks to the intereviewer for the Bourne shell, which set a very high standard for "glue" languages and deserves a lot of credit for making software re-use viable long before object-oriented programming was touted as being the enabling technology.

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