29 May
2009
29 May
'09
7:12 p.m.
Tony Duell wrote:
I was actually referring to the second. I don't consider the first one
to be multi-CPU at all. I was mostly referring to S/370 systems with
which I have personal experience, although I understand they weren't, by
any means, the first.
Peace... Sridhar
There ARE
multi-CPU vintage systems. Some of the CPUs in question were
many, many boards full of chips.
I thnik you need to distinguish between :
Multi-chip CPUs, like many older minicomputers, where the CPU may well be
hundreds of chips, but where there is really only one CPU running one
program at a time
And
Multiple CPUs, where the CPUs may be single chips or boards of many
chips, but where there are several programs running at the same time,.
one on each CPU. And then you have the case where there are several
microporcessors in the cabinet, but some of then run programs from ROM
only (you can't run user programs on them) for things like I/O, disk
control, etc.