Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uunet!pdn!oz!alan
From: alan@oz.nm.paradyne.com (Alan Lovejoy)
Newsgroups: comp.arch
Subject: Re: Motorola Delta mips-ratings versus new MPC mips-ratings
Keywords: curious
Message-ID: <7550@pdn.paradyne.com>
Date: 17 Mar 90 23:55:39 GMT
References: <37103@mips.mips.COM<
Sender: usenet@pdn.paradyne.com
Reply-To: alan@oz.paradyne.com (Alan Lovejoy)
Organization: AT&T Paradyne, Largo, Florida
Lines: 32

In article <37103@mips.mips.COM< mash@mips.COM (John Mashey) writes:
<I noticed in the recent announcements that the 20Mhz MPC-100 is rated at
<27 mips, and the 25MHz MPC-200 rated at 33.8 mips.
<
<I thought that the Delta 8864SP (88K with 128K cache @ 20Mhz) was rated
<at 17 mips, and the 25Mhz version at 21 mips., and I thought the MPC
<systems used the same boards.
<
<1) On the surface, it seems surprising that these machines just jumped
<a factor of 1.6X in performance....
<
<2) Could anybody that knows say:
<	a) Do the MPC machines have a different memory system than the
<	older machines?
<	b) Did the compilers get a bunch better?
<	c) Or is there some other reason for this that I've missed?
<-- 
<-john mashey	DISCLAIMER: <generic disclaimer, I speak for me only, etc>

The only thing I've seen on this is a comment by a Moto spokescritter in
EE Times (I believe) to the effect that the MIPS ratings were based on 
Dhrystones relative to the canonical VAX figure of 1757/second.  Since 
27 x 1757 = 35140, which is about what other 20MHz 88k processors do, one 
might be tempted to conclude that the performance increase in this case is 
mostly due to differences in the rules or standards of measurement :-).



____"Congress shall have the power to prohibit speech offensive to Congress"____
Alan Lovejoy; alan@pdn; 813-530-2211; AT&T Paradyne: 8550 Ulmerton, Largo, FL.
Disclaimer: I do not speak for AT&T Paradyne.  They do not speak for me. 
Mottos:  << Many are cold, but few are frozen. >>     << Frigido, ergo sum. >>