Re: Boeing 777 - Totally Irresponsible?

Date:         04 Jan 97 03:55:52 
From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
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>A single program with a million lines of code will be more prone to
>errors than 100 programs with a thousand lines of codes each.

>If your software runs on a proven operating system, or on different
>computers, modules are not likely to pollute other modules with memory
>leaks etc. So you are looking at certifying separate smaller modules
>instead of one huge module. The ods of errors in smaller modules is much
>smaller than in a larger module.

However, the odds of inter-process communication failures increase,
so all you've done is move the errors from one part of the system to
another.  Given how much of my time ends up being wasted on various
sorts of interoperability problems between software and hardware that
is supposedly standards-compliant (and thus interoperable), I would
not be in *too* big a hurry to make this trade.

That's not to say monolithic, mainframe style computing designs are
a good thing -- my employer's entire business is built upon servers
which do just one job (file service), but are therefore simple enough
to do that one job faster, more reliably, and with cheaper hardware
than a "Swiss Army knife" approach.  We still have to talk with the
rest of the world, though, and it's not always trivial to do correctly.

Karl Swartz	|Home
Moderator of sci.aeronautics.airliners -- Unix/network work pays the bills