[HECnet] Another TOPS-10 DECnet problem

You had a 20 that would handle 600 students in 1977/???/? Yikes!!? What kind of monster was that and how did you do this without melting? As I recall, the maximum number of lines that an RSX-20F front end would handle with a full complement of DH11's is 128.? I have heard of a site (Case Western Reserve) having more than one front end handling lines, which I would imagine could get you up to 256.? There was also another site that moved the terminal handling code out of section 0, which was probably a great idea. I also recall that the maximum job number that you could get on CFS was 512 for a maximum of 128 jobs per node. But I don't think I'm aware of any 20 doing more than about 70 active users without some serious load issues.? That would be a mix of text editing, email and maybe some iterative program development.? At Columbia, our standard 20 configuration was two DF20's (?) for (I think) 3.5 MW.? We experimented with 'maxing' a 20 out with two DH20's and an MA20 for 3.75 MW, but it did not perform substantially better. I'm not sure what the limiting factor was, whether it was paging or CPU.? If it was paging, then assuming you weren't doing too many multi-section programs, a 32MW Toad would clearly handle a higher number of users (and perhaps far higher), but you are then talking about contending for other things, RH20's, disks and at some point, you are just out of CPU. There was a multi-processor version of TENEX, but nothing like that exists in any Tops-20 source that I've seen.