Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!caip!im4u!ut-sally!pyramid!pesnta!valid!gelfand
From: gelfand@valid.UUCP (Brooks Gelfand)
Newsgroups: net.followup
Subject: Re: FYI: VM systems on the net
Message-ID: <503@valid.UUCP>
Date: Mon, 28-Jul-86 14:53:04 EDT
Article-I.D.: valid.503
Posted: Mon Jul 28 14:53:04 1986
Date-Received: Wed, 30-Jul-86 04:03:19 EDT
References: <455@valid.UUCP> <653@glasgow.glasgow.UUCP> <494@sunybcs.UUCP>
Organization: Valid Logic, San Jose, CA
Lines: 25

> >Since VM handles all the I/O, it is an excellent system for people who
> >who are debugging Physical IOCS. Vm will not let the user move the 
> >disk heads outside their alloted area even with PIOCS. Thus one user
> >cannot corrupt anothers files by accident  or even on purpose.
> 
> We recently got a 3081 running VM.  When the 3081 itself crashed,
> EVERYBODY's files were trashed!
> 
> I shall never understand how you can make a computer more reliable
> by simulating it on another computer.
> -- 
> Col. G. L. Sicherman
> UU: ...{rocksvax|decvax}!sunybcs!colonel
> CS: colonel@buffalo-cs
> BI: colonel@sunybcs, csdsicher@sunyabva

No operating system, by itself, can imporve hardware reliability -
VM, UNIX, or BRAND-X. If the hardware itself fails, the system comes down
unless you have duplicate hardware such as a TANDEM system. When the
hardware crashes you will loose work in progress - the files in core.
However, you should not have lost any files on disk unless you were 
writing to them at the time of the crash. Or did you perhaps have a
disk head crash?

Brooks Gelfand