Moving buttembler programs above the line 510

Test&Set atomic instruction was available on 360 ... basically for multiprocessor locking-syncronization ... 360-65 MPs and 360-67 MPs.

360-67 was the only 360 with virtual memory support ... very similar to what was later introduced in 370. 370-67 also had both 24-bit and 32-bit virtual addressing modes (32bit was dropped in 370, however 31bit addressing was later introduced with 370-xa on 3081s).

360-67 multiprocessing was announced with up to 4-way and a box called a channel director .... which allowed all processors to address all channels. I don't know of any 4-way machines that were build and I'm only away of a single 3-way machine was built ... the rest were 2-way SMPs.

The 360-67 "channel director" had a bunch of switch settings that could parbreastion the configuration, buttociate various components in subset configurations, etc. The values of the switch settings were available in half-dozen or so control registers (used these days for access registers). The one 3-way SMP channel director also had a feature that it was possible to reset the channel director switch settings by loading values into the control registers.

at the science center

charlie was doing a lot of work on fine-grain locking and serialization (with cp67 and 360-67 smp) and invented a new instruction ... which was given a mnemonic of his initials, CAS. Then we had to come up with a name for the new instruction that matched his initials ... and compare-and-swap was born ... various smp and compare-and-swap posts

trying to get compare-and-swap into 370 architecture ... the owners of the 370 architecture in POK said that there wasn't a big demand for any (new) SMP-oriented instruction (at least in the POK "batch" operating system ... they were satisfied using test-and-set instruction for the few locks that they had implemented for SMP support) ... and they suggested coming up with a non-SMP specific justification; thus was born the use of compare-and-swap for "interrupt-enabled", multi-threaded code (whether running on uniprocessor or multiprocessor hardware) ... and the description that was in the compare-and-swap programming notes (which have since been moved to the principle of operation appendix).

the 360-67 blue card had the layout for the 360-67 control registers.

my trusty "blue card" i borrowed from the "M" in GML ... and has his name "stamped" on the front .... aka GML (precusor to SGML, HTML, XML, etc) was also invented at the science center ... and "GML" are the three last name initials of the people involved at the science center:

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