Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!wuarchive!brutus.cs.uiuc.edu!usc!henry.jpl.nasa.gov!elroy.jpl.nasa.gov!jpl-devvax!grieggs
From: grieggs@jpl-devvax.JPL.NASA.GOV (John T. Grieggs)
Newsgroups: comp.sys.atari.st
Subject: LHARC takes over?  Sure hope not!
Keywords: Ack!  Pffft!
Message-ID: <6716@jpl-devvax.JPL.NASA.GOV>
Date: 2 Jan 90 23:47:15 GMT
Reply-To: grieggs@jpl-devvax.JPL.NASA.GOV (John T. Grieggs)
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 47

Gee, I certainly hope that LHARC doesn't take over.  Why?  Three reasons.

	1:  It doesn't exist on many machines.
	2:  It isn't that good.
	3:  It's as slow as molasses.

I did a benchmark on my AT clone at work, using a variety of filesets and
all the compression programs I had around.  If there is interest I will
post the actual numbers.  The summary is that PKZIP wins hands down in
most of the areas of interest to me - it is fast, and it compresses trees.
The problem with PKZIP (and PKARC as well) is lack of source.

ZOO source is available in the PD, and ZOO has already been ported to
most machines (right?).  ZOO is comparable in speed and compression to ARC,
and slower than PKARC or PKZIP.  However, it does do trees, and thus has
a real advantage over ARC.

LHARC was abysmally slow.  Compression was better than ARC or ZOO, but no
better than PKZIP. It takes sooooo looooong to do simple operations that it
is simply not usable (IMHO).  Does trees, tho.

The nice thing about ARC is that it exists on all machines, and everyone
has ported it in such a way that it stays compatible.  If you read the 
comments with LHARC for the ST (which I have run a number of times, by
the way), there is mention of incompatibility.  I believe the latest
version supports some of the additional encoding methods, but there were
still some arbitrary differences.

The only real advantage I can see to using one of the newer compression
programs is the ability to compress trees.  For a new compression program
to be successful it must be fast, readily available for any operating
system, and totally compatible across all operating systems.  ARC is
even usable on a MAC!  For LHARC or ZOO to be successful, it needs to be
ported to all of the common machines out there, from the Atari 800XL 
to the IBM 3090.  ARC is there...

Well, I haven't been in a good flame war for a while.  Have fun, if
you must.  I personally think that LHARC is not the way to go, and I
am sure that all of you who disagree will let me know.

_john

-- 
John T. Grieggs (Telos @ Jet Propulsion Laboratory)
4800 Oak Grove Drive, Pasadena, Ca. 91109 M/S 301-260A    (818) 354-1453
Uucp: {cit-vax,elroy,chas2}!jpl-devvax!grieggs
Arpa: ...jpl-devvax!grieggs@cit-vax.ARPA