As a "junior assistant probationery trainee IBM systems engineer" in a
Chicago branch office, I worked on a project that needed a lot of data
center machine time. I ran a benchmark for a custom at the IBM Des Plaines
data center and used a 360/40 that had an unusual toggle switch on the
front panel with the labeling on the switch being "virtual"/"real". It was
a few years before I understood what that meant. At that time, also, the
downtown Chicago IBM data center had a 360/67 which I always used in 360/65
mode.
Jim
At 07:49 AM 8/6/2006, you wrote:
Phil Smith III wrote:
> Gabe reminds me that the 360 didn't run VM; I did use it, but it was
> the 370/158 with 2MB that I used to use VM on.
360/67 was the only (standard) 360 with virtual memory support. it had
both 24-bit and 32-bit virtual addressing options (you didn't see more
than 24-bit again until 370-xa with 3081). 360/67 multiprocessor also
had channel director ... which supported all processors accessing all
channels (standard 360 & 370 multiprocessors only provided for common
memory addressing ... the rest of the infrastructure, including
channels, were partitioned, specific to processors).
cp67 was developed by the science center
http://www.garlic.com/~lynn/subtopic.html#545tech
... supporting virtual machines and virtual memory. cp67 was released to
customers. there had been an earlier cp40 developed on a custom modified
360/40 with virtual memory ... pending availability of a 360/67.
Jim Bohnsack
Cornell Univ.
(607) 255-1760
