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by crazyd987 1456 days ago
My memory of the PDP-11 is different. However, the pdp11 is/was a weird collection of systems, from tiny little single chip implementations to run a VAX console, upto large racks of boards to make up a cpu and fpu like the 11/70. I mainly worked on 11/44's an 11/73's which both shared a 16bit paged address space, (with no cache that I remember).

They had more physical memory (256k and I think 4M) than could be addressed by the instructions(64k).

The pages where 8k - so eight of them, and waving them around required an OS mapping function call.

The IO controllers where asynchronous, and the OS did preemptive multiprocessing and the problem-space was larger than 64k, and faster than the disk-drive, so multi-processing and locks where required to address it.

We used C and assembler on them. C was nicer than assembler to work with.

I don't see a difference of-kind between the pdp-11 and current computers. I do see a difference of 'know-ability' of the software stack that makes up a system.

There are so many external dependencies in the systems I have worked on since, many of them larger than the systems that loaded into that pdp-11, so being certain that there is no fault was almost always a pipe-dream. Automated tests helped - somewhat.

Often, confidence is based on the 'trajectory' of the rate of bugs discovered.