I initially wrote in response to this thread: >>>> - A Tektronix 4132 Unix workstation using a National 32016 CPU and >>>> a 4.2bsd port called UTek
>> Jon responded: >> >>> Gee, how does it perform? I built a clone of a Logical Microcomputer Co. >>> 32016 Multibus system and got it working. >>> But, it was glacially slow! I did have some memory that was likely a >>> little slower than the stock memory, but it wasn't insanely slow. But, >>> firing up certain >>>things like editors was just maddening. And, I'm not >>> talking about Emacs, just vi. I eventually got a MicroVAX-II to replace >>> it, and, yes, that DID have a cache >>>to speed up the memory, but it was quite a difference. ..and I responded with: >> Well...considering the era, it wasn't too bad. By today's standards, yeah, >> it's pretty darned slow. >> Vi starts up pretty quick, even with a couple of terminals running on it. >> It runs rogue pretty nicely, quick enough for multiple people to play it at >> once. >> >> The machine has 7MB of RAM, which really helps. Without additional RAM, >> there's only 1MB on the main board, and running it with just 1MB makes it >> >>incredibly slow. There isn't any external cache. And Jon wrote back: >Ahh, that may be part of the difference. I can't remember how much memory I >had on it. I would not be surprised if it was as tiny as 128 KB, or maybe 256 >KB. >I'll check my schematics to see how many address lines were >implemented.'' With that little memory, even with cache, it was bound to be slow, and probably ended up paging a lot. > > If mine hadn't performed so poorly, I might have continued to use it, and > upgraded parts. > I got versions of Genix and Xenix with it. These were likely early ports for > the 32016, and may have had poor implementations for the MMU for instance. The real difference was likely that UTek was a pretty true port of Berkeley 4.2 for the VAX, which was a really good fit for the mature (for the time) virtual memory management features offered by BSD Unix, and the demand-paged virtual memory capabilities of the 32016 chipset. -Rick
