[Info-vax] Reading Gordon Bell's VAX strategy document

[gah4]

On Sunday, September 24, 2023 at 7:29:05 AM UTC-7, Johnny Billquist wrote:

(snip)

> VMS was never expected to run on something with 64K. You couldn't even 
> run a reasonable PDP-11 on that little memory at that point. (I said 
> responable, for anyone dragging out a minimal RT-11 system.) 

> But VAX was most definitely designed for getting programs more memory 
> efficient. More addressing modes, more things done in microcode to deal 
> with things in a single instruction. Very variable length 
> instructions... All was about memory cost. Which made a lot of sense 
> between 1970 and 1985. After that, memory was becoming so cheap there 
> was no reason for the optimization angle the VAX had taken. And you had 
> the rise of RISC. 

IBM S/360 was designed around about 1963.

There are machines down to 8K bytes, all magnetic core memory.

The first use of semiconductor RAM in a commercial computer is
the memory protection keys in the 360/91, four bits for every 2K
of core.  That is built from 16 bit bipolar RAM chips.