Re: Papers on the Ariane-5 crash and Design by Contract

[Alexander Anderson <sandy@almide.demon.co.uk>]

In article <tz8ohcjv7cc.fsf@aimnet.com>, Thomas <nouser@nohost.nodomain>
writes 

>I think the lesson to be learned from this is that projects should
>choose hardware that is sufficiently powerful to let the software
>engineers implement their software without making dangerous
>compromises and without having to spend a lot of their time on
>worrying about how to squeeze complex algorithms into inadequate
>hardware.  With more powerful hardware, you don't have to disable the
>runtime checks in a language like Ada in the first place, and you can
>afford to add adequate exception handling code.  While on a rocket
>every gram and watt counts, we are talking maybe 10-20% more memory
>and performance.  More powerful hardware might also have permitted a
>simpler, more easily tested and maintained design overall.


    "Might also have"?  Hmmm...
  

    I think this is wrong.  Total bull wrong.  Good Software Engineering
arises out of the organisation of good social structure.  The flow of
communications.  Nothing else.  In the end, it's down to people really
_talking_ to eachother.  A Challenger disaster doesn't go away just
because you have a springier rubber in your O-rings.  The malaise that
caused that disaster will cause something to fail somewhere else.


    And what's this talk of weight and watt?  A high-end pentium PC
today has millions of times more storage and millions of times more
speed than the systems that took Apollo into lunar orbit.  And
undoubtably weighs and takes far less power too.  Communication made it
happen, I mean -- all they had for RAM at the time was a bulky cube of
64,000 _hand_threaded_ ferrite beads called core-store.


    So I say what you're "Might also have" saying is just plain wrong.




Sandy
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