Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!killer!elg
From: elg@killer.DALLAS.TX.US (Eric Green)
Newsgroups: comp.sys.amiga
Subject: Re: Amiga floppies (was: Re: Blitter vs. 80386)
Message-ID: <5305@killer.DALLAS.TX.US>
Date: 26 Aug 88 03:58:17 GMT
References: <8808180059.AA05505@cory.Berkeley.EDU> <2505@sugar.uu.net>
Organization: The Unix(R) Connection, Dallas, Texas
Lines: 31

In message <2505@sugar.uu.net>, peter@sugar.uu.net (Peter da Silva) says:
>In article <8808180059.AA05505@cory.Berkeley.EDU>, dillon@CORY.BERKELEY.EDU
$	(Matt Dillon) writes:
$
$$ 	Using an IBM-AT 386 @ 16MHz, it still takes up to three seconds to
$$ go through about 200 entries (in the 4 or 5 directories I had in the path)
$$ to find the executable I wanted.... In otherwords, a DISKBOUND operation.
$
$You're comparing apples to oranges. MS-DOS shouldn't be your standard for
$comparison... UNIX should.

Unix, though, still is no speed demon on searching directories,
insofar as finding a particular program to run. Directories, at least
under old AT&T versions, are sequentially organized in no particular
order -- meaning an O(n) search time, where n is the number of files
in all those directories.  That's why csh and ksh have hacks in them
to speed up finding programs (hash tables, etc.), which are just as
much hacks as the "fastdir" programs on the Amiga.

Of course, Unix DOES have disk caching, while MSDOS doesn't... and
most Unix systems DO have faster disk drives than MSDOS machines...
but, all in all, the performance for directory searches should be
similiar between the two systems.

[Note: All the Unix info is from the Bach Book, which means it's
probably for some old generic AT&T version... I'm not up-to-date on
everything the Berzerkoids have done with BSD4.3).

--
Eric Lee Green    ..!{ames,decwrl,mit-eddie,osu-cis}!killer!elg
          Snail Mail P.O. Box 92191 Lafayette, LA 70509              
       MISFORTUNE, n. The kind of fortune that never misses.