Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!lll-winken!maddog!brooks
From: brooks@maddog.llnl.gov (Eugene Brooks)
Newsgroups: comp.arch
Subject: Re: The Killer Micro From Hell
Message-ID: <42527@lll-winken.LLNL.GOV>
Date: 27 Dec 89 16:38:58 GMT
References: <42007@lll-winken.LLNL.GOV> <3090@umn-d-ub.D.UMN.EDU>
Sender: usenet@lll-winken.LLNL.GOV
Reply-To: brooks@maddog.llnl.gov (Eugene Brooks)
Organization: Lawrence Livermore National Laboratory
Lines: 36

In article <3090@umn-d-ub.D.UMN.EDU> rhealey@ub.d.umn.edu (Rob Healey) writes:
>	Was the code running on the XMP/YMP optimized to the Cray architecture
>	as much as the code running on the R6000 was optimized to the MIPS
>	architecture?
We have Cray machines on site, the MIPS R6000 system was a compile and go
benchmark run done by the vendor.  Just which system do you think the code
was "tuned" for, within the limits of keeping the code portable, readable
and maintainable?

>	Hmmm, I seem to remember the
>	Cray's being touted for their VECTOR capability in addition to
>	"respectable" SCALAR performance. Can the 6000 do seamless vector
>	operations too?
The scalar performance of the Cray machines is no longer "respectable",
is it!   I do not believe that the R6000 has vector registers, but
I haven't seen technical data on this issue.
>
>	Just asking if comparing Apples to Oranges and saying Apples are better
>	is a valid claim?
I was not comparing apples to oranges.  I was comparing the performance of
compiled C code on two computers...  In the best notion of benchmarking,
the code was one of MY compute bound applications.  Your milage will vary.
>
>	My main reason for responding to this excited article is that
>	I find it disturbing that ALOT of people pay attention only to
>	MIPS, or only one aspect of a system, and not to full systems as a
>	whole. To over simplify: 
My main reason to reponding to this article is that there are a lot
of people with their heads in the sand who still think that traditional
supercomputers or mainframes are good buys.  I hate to see people get
bushwacked by Killer Micros when they can just ride the wave.  Killer
Micro powered systems are no longer just more cost effective, for
scalar application codes they are faster...


brooks@maddog.llnl.gov, brooks@maddog.uucp