Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uunet!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!rpi!uupsi!rodan!jfbruno
From: jfbruno@rodan.acs.syr.edu (John Bruno)
Newsgroups: comp.sys.atari.st
Subject: 68030 speed increases (was Re: Atari TT 030 Launched!)
Keywords: Atari TT
Message-ID: <3647@rodan.acs.syr.edu>
Date: 6 Jun 90 20:23:21 GMT
References: <1990Jun5.143231.4977@watserv1.waterloo.edu> <13266@wpi.wpi.edu> <81214@tut.cis.ohio-state.edu> <1990Jun6.044350.20403@cbnewsh.att.com> <10373@batcomputer.tn.cornell.edu>
Reply-To: jfbruno@rodan.acs.syr.edu (John Bruno)
Organization: Integrated Healthcare Technologies, Inc.
Lines: 36

In article <10373@batcomputer.tn.cornell.edu> riley@tcgould.tn.cornell.edu (Daniel S. Riley) writes:
 >In article <1990Jun6.044350.20403@cbnewsh.att.com> wolf@cbnewsh.att.com (thomas.wolf) writes:
 >>Could you contain your mindless ravings?  The poster mentioned that 1/3
 >>increases were with non-030 applications (ie those written for the MC68000).
 >>I seriously doubt your claim that a ~9-fold increase was achieved on the A2500
 >>WITHOUT optimizing the code towards a 68030.

I doubt it too!

 >
 >That wasn't mindless ravings.  Seriously, that 1/3 number confuses me--it
 >should be lots higher.  Going from a 16 bit to 32 bit machine and doubling
 >the clock speed (8 MHz to 16 MHz) should give you at least a factor of 4,

How do you figure that???? I would expect a CPU with twice the clock rate to
execute instructions twice as fast.  However, the difference between a 32
bit bus and a 16 bit bus will not double your execution speed (unless every
single instruction in the testing program operates on 32 bit objects). Sure
there will be more speed improvement, but definitely NOT enough to double the
speed.  

You can always whip up some special optimal program that will run 4 times
as fast with the above configuration. That is, if you just want to impress
those people that like to say "MY machine does more Giga-hoozits than..."
In real life, though, it don't work that way.  I still feel that the
most important and effective things you could possibly do to speed up your 
computer is to learn how to type and operate a mouse faster and get a faster
hard drive. Even a ZILLION-MHz machine is gonna twiddle its thumbs waiting
for you (operating at about 3Hz) to tell it what to do.

[ Rest of 68030/68000 discussion ZAPPED ]

---jb

PS - A request for posters to this group: Please make sure that the subject
 of your article agrees with the body of your article!!!!!!!!!!!!!