> The rule I use is simple :
> If the CPU is one chip (like a Z80, or a pentium) or a chipset that's
> always used together to make that CPU (like a F11, or the early IBM 6000
> CPU) -> It's a micro
> If the CPU is a lot of standard chips (gates, flip-flops, ALUs, bit-slice
> stuff), and it fits into at most a couple of 6' racks -> it's a mini
> If the CPU takes up most of the room -> it's a mainfame.
> If it meets the 3M critera (Megabyte, Megapixel, Mips) -> it's a workstation.
> Now, this leads to some interesting ones. By that definition, a PDP11/23
> is a micro. But a PDP11/34 is a mini. The 370-on-a-card is probably also
> a micro.
> Note that 'workstation' says nothing about the CPU. I'd claim a Sun3 is a
> worktation _and_ a micro. A PERQ 2 is a workstation and a mini.
> Those definitions aren't perfect, but they seem to work for me.
I think ruling the CPU isn't exatly the way to describe this
classes, since even a mainframe type computer can have singe
chip processors, and a micro can consist of a whole chip graveyard.
But your Note leads a trace: try the design goal as class.
So, a mainframe is a general purpose computer specaly designed
to transport, merge and modify data like a big steel plant
modifies iron. Using only a small number of programms but serving
the same task a _huge_ mass of users. Usualy these are just /370ish
designs.
A Mini is some kind of 'big' computer designed to serve
a lot of people in an individual sense, giving every
user (and sometimes even every single programm) the
feeling of a complete independant computer. The OS is
wasing a lot of resouces (not needed on mainframes) to
ensure coexistence, fast programm change etc. The OS is
mostly unix-like.
A Workstation is 4M (you just missed the Megabucks :).
A workstaton serves the needs of only one user.
The OS is in most cases very graphic-able orientated.
An average PC is just a workstation on a lower level, running
several different application (maybe even at the same time)
to serve every person as his own computer like a mini, but
without sharing anything. The OS is almost complete graphic
orientated.
I think this sceme is sufficient for all GPC. If you miss
the micro, its just because it represents no class of its
own. The micro can be just a very small mini, or he is a
PC(Workstation). Didn't the Wozniak once state that every
micro before the A2 was just a small singe user mini ?
Gruss
H.
--
Ich denke, also bin ich, also gut
HRK
Received on Wed Sep 09 1998 - 11:11:33 BST