Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!csinc!rpeglar
From: rpeglar@csinc.UUCP (Rob Peglar x615)
Newsgroups: comp.arch
Subject: Re: The Killer Micro From Hell
Summary: Atta boy, Eugene.
Message-ID: <158@csinc.UUCP>
Date: 29 Dec 89 15:19:27 GMT
References: <42007@lll-winken.LLNL.GOV> <3090@umn-d-ub.D.UMN.EDU> <3091@umn-d-ub.D.UMN.EDU>
Organization: Control Systems, Inc., St. Paul MN
Lines: 86


Eugene (Brooks) has already responded to this, quite elegantly.  Just
wanted to throw in my $.02.  

In article <3091@umn-d-ub.D.UMN.EDU>, rhealey@umn-d-ub.D.UMN.EDU (Rob Healey) writes:

> 	Being my head is currently in Minnesota I'd say it might be in
> 	a snow bank but definitely NOT in the sand. What makes you think
> 	the bigger systems won't adopt the same technology as the "killer
> 	micros" and thus the costs go down. How good will your scalar 6000
> 	do HUGE data sets that require movement to and from I/O? The MIPS
> 	performance of the 6000 may well beat a super or mainframe but
> 	what about scalar problems that require heavy I/O? Will your
> 	low cost workstation be able to handle those problems better?
                                                              ^^^^^^

If the meaning of "better" is absolute performance, no, not today - but
as Eugene says, "ride the wave".  No will be yes, and Soon.

If, on the other hand, the meaning is "price/performance", most assuredly
yes, yes, yes - today, tomorrow, and forever more.

There are many meanings.  Be specific.

As far as being in the snow banks, I'm there too - fortunately, it's my
feet, not my head :-)


> 
> 	Super computers and mainframes ARE GREAT buys when LOTS of
> 	users need to be serviced. You'd be foolish to think 1000 users
> 	would be best served by networked workstations maxed out with disk
> 	and memory so they can run at top speed. That situation requires a
> 	heirarchy of disk, CPU and memory networked together very carefully.

Look around you.  The very same "systems" - in the broad sense of the word -
i.e. many components - are indeed overtaking centralized, vertical machines.
There was a long thread on this topic (degree of centralization) a while
back.  Personally, I held the same opinion (as described above) for many
years, and have since changed my mind.  Rather, opened my mind.

As in almost every problem to be solved, there are many solutions.  Use
what's best for you - and don't be afraid to change.  If a large super
serving 200 people gives those people the most "numerator" (MIPS,Flops,
I/Os,etc.) for the "denominator" (dollars,time,effort,etc.etc) then great,
use the super.  If not, swallow hard and accept the Killer Micro as a
fact of life.

> 
> 	My original point is being totally ignored here:
> 
> 	MIPS is useless if the data can't flow in and out of the CPU
> 	at the rating of the CPU. The "Killer Micro" is a glorified oscillator
> 	when it has to wait for I/O to complete. DON'T use a diskless
> 	"Killer Micro" low cost workstation to try to do REAL work. Let the
> 	manufacturer nickel and dime you for fast disks and fast memory in
> 	vast quantitys.  While the MIPS arguement might work on the
> 	ignorant IBM PeeWee masses, technical people know better than to
> 	just look at one aspect of a problem and think the problem solved
> 	based only on that one aspect/criteria. When you solve a problem with
> 	a computer you have to weigh MIPS vs memory vs disk vs networking vs ??.
> 	You'll screw yourself over BIG TIME if you totally ignore any of the 4
> 	in heavy favor of 1 or 2 of the factors.
> 
> 	This is my point, it looks like I picked the wrong article to bring it
> 	out on.

Editoral note - you aren't scoring any points for phrases like "REAL work",
"PeeWee masses", and "BIG TIME".  

Anyway, you should carefully look at the issue of CPU starvation on some
of the very machines you tout - like the Cray-2.  Some (not all) of the
smaller machines exhibit much less CPU starvation.  The ETA-10 is (was)
another notable example of real and potential CPU starvation as an
architectural flaw.


There will always be room for big supers.  The room, however, is becoming
smaller.  Don't get squeezed.

Rob
-- 
Rob Peglar	Control Systems, Inc.	2675 Patton Rd., St. Paul MN 55113
...uunet!csinc!rpeglar		612-631-7800

The posting above does not necessarily represent the policies of my employer.