The debate on what per say is a mini...

From: Chuck McManis <cmcmanis_at_mcmanis.com>
Date: Sat Dec 16 13:13:20 2000

At 11:35 PM 12/15/00 -0700, Clint wrote:
>I hate to jump into a philosophical argument, but here goes....

Oh they are the best kind, everyone can be right at the same time ;-)

>Mainframes are big/powerful machines that sit in a secured area and
>are driven by terminals (X,PC,3270,etc) on peoples desks. They cost
>big bucks.

In the "modern" world, what about an Intel server that is locked up in a
co-location facility at some ISP and is being driven by web browsers ?
(some of which (netpliance) are effectively terminals?)

>Micro-computers are small/weak machines that sit on peoples
>desk so they can surf the web and play solitare. They cost
>next to nothing.

My PC sits under my desk, only the monitor/keyboard is on top :-)

>Workstations are more powerful, but still small... They cost
>more than micros.

Cost only? When I worked at Sun we worked in something like video
resolution or max memory, but the bottom line has traditionally been cost :-)

>Mini-computers is a nitch that has gone away (or been replaced
>by workstations). They were less powerful than a mainframe, but
>orders of magnitude cheaper and could sit next to a persons
>desk. This was more of a marketing trick to help scientists
>convince the bean-counters they weren't buying a real computer,
>just a glorified calculater (PDP == Peripheral Data Processor).
>A calculator doesn't need to be locked in a room with all the
>other calculators :)

Actually this isn't a fair description. Mini-computers most definitely have
_not_ gone away and you will see a resurgence of mini-computer like
features. Specifically, mini-computers are computers that are
*configurable* with a wide variety of peripherals. This lets them be used
for lab experiments, or process control, etc. PC's have done this in the
past but the lack of I/O features on the mainstream "PC" of today are
hindering their use in the lab and process control. Also the lack of
documentation that many people have complained about.

Collectively this is the "cost" model and generally follows order of
magnitudes:
         < 4K Micro
         < 40K Workstation
         < 400K Mini
         < 4M Mainframe
         < 40M Super
I added the last bit because we haven't been including "what's a
super-computer" in our lists. I heard a great talk by a guy who works at
LLNL and the complaints the scientists had at the purchase of ASCI WHITE
(super computer made out of parallel RISC chips) because it simply could
not be used to program the kinds of models they used for nuclear simulations.

>PS It is unfair to compare mainframes of old to PCs of new. To be
>fair, compare an 11/780 with what was available at the time: the
>Apple ][, Commodore, IBM PC(?). These machines couldn't support
>multiple users, imagine running a university off of a cluster of
>Amigas!

But Clint, this is in fact the point. Can one come up with a definition
that transcends what the marketroids called micro, mini, and mainframe of
their day?

>PPS A modern mainframe would have no problem out-performing
>a PC for REAL work. It's designed to do just that.

Agreed, check out the spec's for the IBM S/390 (I mean Z900 :-)

--Chuck
Received on Sat Dec 16 2000 - 13:13:20 GMT