Xref: utzoo comp.arch:6800 alt.next:233
Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!rutgers!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.arch,alt.next
Subject: Re: The NeXT Problem
Message-ID: <5086@cbmvax.UUCP>
Date: 24 Oct 88 17:51:20 GMT
References: <1988Oct23.002818.20634@utzoo.uucp>
Organization: Commodore Technology, West Chester, PA
Lines: 41

in article <1988Oct23.002818.20634@utzoo.uucp>, henry@utzoo.uucp (Henry Spencer) says:
> Xref: cbmvax comp.arch:7110 alt.next:228

> In article <5024@cbmvax.UUCP> daveh@cbmvax.UUCP (Dave Haynie) writes:

>>no trouble competing with the installed 68020 systems...
  ^^
   Whoops.  

> Your statement is correct as it reads (they will not have no trouble, i.e.
> they will have trouble), but that's probably not what you meant.  The 68030
> is *not* orders of magnitude faster than the 68020, 

A 68030 can run BETTER than TWICE the speed of a 68020+68851 MMU, if you 
let it.  Sun 3s have a somewhat faster MMU, but no matter what you do,
a 25MHz 68020 isn't going to be able to read a longword every two
clock cycles.  A 68030 using burst fills and both caches will usually
preform about as fast with a few wait states as a 68020 with no wait
states, running at the same speed.

> especially if you are
> comparing fast 68020 systems with mediocre 68030 systems.  (Do remember that
> you should probably normalize for memory access times, not raw clock rate,
> when comparing implementations.)  It's not at all obvious to me that NeXT
> is going to blow Sun away.

Of course, and I never implied that they would.  I did imply that a NeXT
machine is more than a match for a good portion of the Sun systems out
there, all Sun 2s, Sun 3/50s, Sun 3/60s, and in fact, any Sun that's not
based on a 25MHz 68020 with a no wait state MMU and no wait state RAM
or a good chunk of external cache.  Then you may have an even match.

Of course, given an even match and even price, I'd pick the Sun.  But
hardware wise, they will compare favorably.

> The meek can have the Earth;    |    Henry Spencer at U of Toronto Zoology
> the rest of us have other plans.|uunet!attcan!utzoo!henry henry@zoo.toronto.edu
-- 
Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
              Amiga -- It's not just a job, it's an obsession