On Sun, Jan 1, 2023 at 12:27 AM Warner Losh <imp@bsdimp.com> wrote:
> On Sat, Dec 31, 2022, 9:38 PM Jonathan Gray <jsg@jsg.id.au> wrote:
>> [snip]
>> Bourne's AsiaBSDCon 2016 talk also lists 1976
>> and goes on to discuss sbrk() use causing problems with ports
>> https://youtu.be/7tQ2ftt3LO8?t=715
>
> And at 5:18 he says he had a vax lab with three vaxen and the Lab's vax port didn't have virtual memory. Bill Joy with 3BSD which had virtual memory. They installed it on the vaxen because they were hitting physical memory limits for some of their programs....

One wonders what is meant by "virtual memory" in this context. I
contend that Unix has had "virtual memory" since moving off of the
PDP-11/20, in the sense of having a virtual address space that was
mapped onto a (possibly contiguous) physical address space. I think
all of these references mean demand paging, possibly with page
reclamation or whole-process swapping under memory pressure.