On Sun, Mar 12, 2023 at 01:21 PM, Drew Derbyshire wrote:
512K? *snort*
DOS/360 could run 16K (1/32 of 512K).
True. And OS/360 could run in 64K. (OS/360 Sysgen manual for R13, Sept 67.)
DOS/360 would IPL in 16K but even with the distribution system supervisor, which supported no more than 10 devices and did not include storage protection among other things, took six of that. A simple 103-line COBOL demo program included with the distribution materials took 13K (linked size including runtime and LIOCS), so that's a no-go. One could certainly do better with Assembly. Although you couldn't use the big Assembler F (44K), or even the 14K Assembler D. You were left with the 10K Assembler D.
I do not have operational OS/360 experience, but I will speculate that OS/360 on 64K was a similar experience. Documentation for later releases stopped talking about 64K.
