Xref: utzoo comp.bugs.4bsd:1705 comp.lang.c:35723 Path: utzoo!utgpu!watserv1!watmath!att!linac!uwm.edu!spool.mu.edu!uunet!mcsun!hp4nl!charon!dik From: dik@cwi.nl (Dik T. Winter) Newsgroups: comp.bugs.4bsd,comp.lang.c Subject: Re: Complexity of reallocating storage (was users command crap) Message-ID: <2886@charon.cwi.nl> Date: 2 Feb 91 01:33:41 GMT References: <15325:Jan2903:19:4991@kramden.acf.nyu.edu> <21548@yunexus.YorkU.CA> <5883:Feb102:05:4991@kramden.acf.nyu.edu> Sender: news@cwi.nl Followup-To: comp.bugs.4bsd Organization: CWI, Amsterdam Lines: 20 In article <5883:Feb102:05:4991@kramden.acf.nyu.edu> brnstnd@kramden.acf.nyu.edu (Dan Bernstein) writes: > In article <21548@yunexus.YorkU.CA> oz@yunexus.yorku.ca (Ozan Yigit) writes: > > To rephrase: ... you are using poor programming techniques. No program > > should make multiple passes over a disk file when it could accomplish its > > task with a single pass with hardly any effort on the programmer's part. > > If you spent a minute putting your priorities into order you'd realize > that this is an entirely ridiculous generalization. If two programs are > just as fast, just as small, and take just as little programmer (and > user) effort, then it simply doesn't matter whether one of them uses > more passes than the other. > Ah, but that is the problem. Just as fast comes in flavors. You have CPU time, real time, IO time and some more. If one of the programs uses more passes it is not equally fast IO time wise (unless you are using SSD on a Cray of course). (Moreover, a program doing IO might well block another program that wants to do IO.) -- dik t. winter, cwi, amsterdam, nederland dik@cwi.nl