In a message dated 7/16/02 2:58:44 PM, [EMAIL PROTECTED] writes:
<<
Could one of you more erudite listers draw a modern day comparison to the IBM
7094 and the IBM 360/50 in terms that I am used to hearing, i.e. CPU speeds
and ram capacities and so forth?
>>
Having worked on those machines ... and on both EARLIER and LATER IBM
machines ... perhaps I can.
The 7094 was perhaps the last of the great 7000 series machines. The 7090 was
intended for business purposes; the 7094 was intended for scientific purposes.
The 7094 was a contemporary of mine when I was employed by UCLA's College of
Engineering.
An "octal" machine, with a weird CISC instruction set. All hard-wired. All
discrete technology.
The Model 50 was part of the watershed System 360 Series, which succeeded all
1400, 7000 and similar series from IBM.
Equally good at scientific and commercial processing (hence the "compass
rose" logo which identified the 360 [ degrees ] series) the Model 50 was
perhaps the worst example of that series, it having never achieved full
release from engineering as there were too many problems with it. The equally
popular Model 65 DID achieve release from engineering, and went on to become
the basis for IBM's first multiprocessor (the Model 65/MP) and IBM's first
model with virtual memory (the models 67 and 67/MP).
Both the Models 50 and 65 were quite limited in RAM. 1024 KB in the Model 65
and 2048 MB in the Models 65/MP, 67 and 67/MP.
ECS ("Extended Core Storage") was available on both the Models 50 and 65 (and
the Model 75 as well). ECS was treated as primary storage by the CPU, but it
was, in fact, an I/O device, and it could be shared among CPUs, as could disk
I/O devices.
The Model 65, which was microcoded as was the Model 50, had a cycle time of
750 nanoseconds, and most operations took multiple CPU clock cycles.
The Model 65's memory was interleaved up to four times, with up to four "core
boxes" being configurable on the Model 65 (eight on the Model 65/MP, Model 67
and Model 67/MP). Each "core box" had a 256 MB capacity.
The "region" allocatable to each "job" (which were "batched") was a minimum
of 64K, but most useful work required at least a 128 KB region.
All storage was "real" (except on the Model 67), which meant that there was a
one-to-one correspondence between the logical and physical address. The
operating system, dubbed OS/360, always resided in "low core", which also
included the so-called "interrupt vectors" (old and new PSWs ... Program
Status Words).
The Time Sharing Option, which was added in Release 20.7 of OS/360, could
handle quite a few simultaneous users.
With OS/370 MVS (Multiple Vistual Storage) Release 3.7 on a System/370
Model/168, more than 100 simultaneous users could be handed with only 6 MB of
main storage.
The Model 168 had a machine cycle time of 80 nanoseconds, and processed some
operations, such as register-to-register operations, in one machine cycle.
My former employer introduced a direct competitor to the System/370 Model
168, which we dubbed, appropriately, the 470 V/6, which featured a cycle time
of only 32 nanoseconds, and was easily 2.7 times as fast as any equivalent
IBM model of those times.
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