Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!uunet!bony1!richieb
From: richieb@bony1.bony.com (Richard Bielak)
Newsgroups: comp.object
Subject: Re: A Rewrite Is *NOT* An Experiment
Message-ID: <1991Apr11.130216.9313@bony1.bony.com>
Date: 11 Apr 91 13:02:16 GMT
References: <44.UUL1.3#913@acw.UUCP>
Reply-To: richieb@bony1.UUCP (Richard Bielak)
Organization: Bank of New York
Lines: 39

In article <44.UUL1.3#913@acw.UUCP> guthery@acw.UUCP (Scott Guthery) writes:
>"We rewrote the X system in Y and it was k times faster.  (Therefore Y
>is not only not less efficient than X and might even be more efficient!)"
>
>Can somebody tell me why statements of this genre from the OO crowd
>(or any other crowd with an axe to grind, for that matter) go
>unchallenged?  Does hype like hope spring eternal?
>
>Com'on, folks.  The fact that the rewrite ran faster says nothing at
>all about the relative merits or efficiencies of X and Y.  The
>efficiency of the rewrite is due at least to 1) the use of Y *AND* 2)
>the fact that it was a rewrite.  For all we know, the rewrite might
>have been 2k faster if X had been used.  In fact, in any rewrite
>situation, I'd bet that 83.7% of the efficiency gains are due to
>simply rethinking the implementation in light of now-known usage and
>load patterns.
>

I agree with you on this point. However, I find that there is too much
emphasis on efficiency and not enough on reliability and correctness.
We are starting a project in which we will re-build a large system and
we will program it in Eiffel. We chose Eiffel mostly because we expect
that our code will be more reliable (partly due to
"object-orientedness" but mostly because of Eiffels pre- and post
conditions).

In our case, it is more cost effective to buy faster machines, then to
suffer software failures in production systems.


...richie



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