> Is that the definitive differentiation between a
mini and a mainframe?
On Fri, 25 Jul 2014, Philip Belben wrote:
I don't know if there was ever a definitive
difference. I expect
different manufacturers used different definitions.
Yes, it was a rhetorical question. It is a vague term CREATED by
marketing people with little technical background. It conveys a sense of
"smaller", but has never been definitively defined, nor even specified in
what dimension(s) it is "smaller".
My personal one, which I think I got from a marketing
leaflet for the
IBM 9370, is that a mainframe requires a computer room, while a
minicomputer shares a room with other equipment (office desks with
terminals, machine tools it controls, or whatever).
Much like, "a microcomputer can be carried; a minicomputer requires
handtruck(s); a mainframe requires a forklift and a union moving crew"
This is not to say that some users didn't put
their minicomputer(s) in a
separate room; but the computers didn't require it.
and mainframes sometimes
had other stuff in the room. I spent a few years
in building 26 at Goddard Space Flight Center. While it might not meet
many modern definigions, in those days both the 7094 and the 360 in the
center room were considered mainframes. But it was a big room, and had an
entire keypunch department in it, along with a tape library, and other
goodies. I spent a lot of time manually digitizing data with a Gerber
Data Digitizer (a giant etch-a-sketch wired to an 026 keypunch)
Yes, EVERY "definition" of "mainframe/minicomputer/microcomputer" has
exceptions. Often, the "definition" is merely a LIST of characteristics,
all of which CORRELATE, but none of which are essentially defining the
categoryt. And, of course, any time that there is more than one
characteristic, OR if that characteristic is merely correlated, then there
are going to be exceptions.
Some of the characteristics are technical, such as construction methods of
the CPU, word length, speed, amount of memory or storage (those
characteristics, of course, get obsoleted and blown away by Moore's law -
the thing in my pocket is NOT a "mainframe")
Although the term LOOKS like a technical classification, it isn't. It was
created by marketing, to convey a feeling. What constitutes a "compact"
car, or a "sports" car? (Don't you hate rhetorical questions?)
Therefore, the most solid definitions end up being the non-technical ones!
price, weight, administrative accounting, staffing, support systems,
hurdles to personal ownership, interest generated and effect on
relationships with neighbors and law enforcement, etc.
The most extreme cases end up being like owning your own 737 or F15.
--
Grumpy Ol' Fred cisin at
xenosoft.com