Do note though that they are both very different from s/360.
Complexity-wise, 1401 and PDP/1 are a bit closer to home computers of the 80s, in that they usually just execute code in a single thread and context and without any protection. They represent an earlier and simpler era of computing.
The s/360 lineage, on the other hand, is an ancestor of our modern computing environment with virtual memory, privilege separation, virtual machines, dynamic linking, and so on.
It’s really quite striking how much of our “modern” computing concepts IBM already did at the time with the s/360 and successors, up to the still alive IBM z.
That does not diminish from the awesomeness of the 1401 and PDP-1 exhibits at all, I highly recommend them!
I'm mainly saying that there were many 'experiments' tried in the olden days, and those plus "the market" give us what we have today. Recall, in the days of the IBM 1401 and DEC pdp-1, the notion of 'byte' as an 8-bit quantity did not exist. ASCII did not exist. The IBM 1401 was a Decimal / Character machine, and could add/sub/mul/div numbers of arbitrary length, in hardware (!). The pdp-1 used one's complement arithmetic. On and On...
Some of that did not really materialize during the System/360 era. A custom version of the model 65 was the only one with virtual memory, for example. And while OS/360 was an architectural marvel on paper see the comments elsewhere in this thread about "The Mythical Man-Month" and how implementing it actually went.
The most common System/360 machine as you would see in the 1960s, was the model 30 with 16 to 64 KB of RAM, a couple disks, and a card reader and printer. It would have been mostly programmed in assembly under DOS (the full OS didn't fit), and mostly batch processing.
The virtual machine behemoths came with System/370 a bit later, the compatible successor series.
With that said, System/360 did innovate quite a lot. Right down to setting the 8/16/32/64 bit pattern for byte and word size, or just the idea of a compatible series of machines running the same software, over the range of 10,000 to 1,000,000+ instructions per second, and from like 8 KB to 8 MB of RAM.
You’re right, so I was careful to say “s/360 lineage”! However, I thought a lot of the advanced concepts already were in some s/360s. Maybe not virtual machines, but that’s more the cherry on top (and pretty wild to me that s/370, which is the next step in the s/360 lineage, already had it).
Complexity-wise, 1401 and PDP/1 are a bit closer to home computers of the 80s, in that they usually just execute code in a single thread and context and without any protection. They represent an earlier and simpler era of computing.
The s/360 lineage, on the other hand, is an ancestor of our modern computing environment with virtual memory, privilege separation, virtual machines, dynamic linking, and so on.
It’s really quite striking how much of our “modern” computing concepts IBM already did at the time with the s/360 and successors, up to the still alive IBM z.
That does not diminish from the awesomeness of the 1401 and PDP-1 exhibits at all, I highly recommend them!