[HECnet] Tops-20 ANONYMOUS FAL Preliminary Testing Results/DAP Query

[Paul Koning]

> On Dec 20, 2019, at 8:51 PM, Thomas DeBellis <tommytimesharing at gmail.com> wrote:
> ...
> But the mini-computer operating systems are just plain cool.  It is amazing what they squeezed into the PDP-8's 12 bit address space and PDP-11's run some of the most interesting collection of OS's that I've ever seen.

If you go far enough back, the space efficiency gets pretty amazing.  There's RSTS-11, which ran 16 timesharing users on a 28kW PDP-11/20. (Not well, but it ran.)  Or RT-11, quite comfortable in 8 kW and a 256 kbyte system disk.  Or DOS-11, which would even run, I think, in 4 kW.

Somewhat earlier still, in 1961 two people implemented the first ever ALGOL compiler in 6 months, and it ran on a 4 kW machine (27 bit).  (It's known to have two bugs.)

	paul