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From: devine@vianet.UUCP (Bob Devine)
Newsgroups: comp.arch
Subject: Re: Disk Striping
Message-ID: <214@vianet.UUCP>
Date: Tue, 4-Aug-87 23:01:09 EDT
Article-I.D.: vianet.214
Posted: Tue Aug  4 23:01:09 1987
Date-Received: Fri, 7-Aug-87 03:46:44 EDT
References: <2432@ames.arpa>
Organization: Western Digital, Boulder Tech Ctr
Lines: 18
Summary: Connection Machine's striping

In article <2432@ames.arpa>, eugene@pioneer.arpa (Eugene Miya N.) writes:
> Very little work has been done on the subject yet a fair number of
> companies have implemented it: Cray, CDC/ETA, the Japanese
> manufacturers, Convex, and Pyramid (so I am informed), and I think
> Tandem, etc.  Now for important perspective: It seems that striping over
> 3-4 disks like in a personal computer is a marginal proposition.
> Striping over 40 disks, now there is some use.  The break even-point is
> probably between 8-16 disks (excepting the fault tolerance case).

  Hillis' Connection Machines supposedly[*] have an implementation of
disk striping where there are 39 disks that each get one bit from
a word.  The word is formed by 32 data bits and 7 ECC bits.  Doing it
in this fashion allows complete recovery even if one disk gets hosed.

Bob Devine

[*] I write 'supposedly' because I only saw a blurb about it.  I don't
    know of dates, availability or ordering info.