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From: das@eplunix.UUCP (David Steffens)
Newsgroups: comp.bugs.4bsd
Subject: Re: Complexity of reallocating storage (was users command crap)
Message-ID: <1020@eplunix.UUCP>
Date: 3 Feb 91 00:23:20 GMT
References: <15151:Feb207:16:0691@kramden.acf.nyu.edu>
Organization: Eaton-Peabody Lab, Boston, MA
Lines: 20

In article <15151:Feb207:16:0691@kramden.acf.nyu.edu>,
brnstnd@kramden.acf.nyu.edu (Dan Bernstein) says:
> ... It's simply not true that any program using more passes must
> use more time; that's only a rule of thumb...

Eh?  Your statement is only applicable when comparing
a one-pass program that uses algorithm XYZ with a two-pass
program that uses algorithm ABC, where the speed of ABC
compensates for the second pass over the file.
A program that reads a file ONCE is ALWAYS faster than a program
that uses virtually the SAME algorithm AND reads the file TWICE.
And that was precisely the point of several earlier articles, namely:
   <19010@rpp386.cactus.org> jfh@rpp386.cactus.org (John F Haugh II)
   <22937@well.sf.ca.us> jef@well.sf.ca.us (Jef Poskanzer)
   <21548@yunexus.YorkU.CA> oz@yunexus.yorku.ca (Ozan Yigit)
-- 
David Allan Steffens       | I believe in learning from past mistakes...
Eaton-Peabody Laboratory   | ...but does a good education require so many?
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