The following message is a courtesy copy of an article
that has been posted to bit.listserv.ibm-main,alt.folklore.computers as well.

[EMAIL PROTECTED] (Rick Fochtman) writes:
> That increased instruction set allows for vastly increased capability,
> in spite of the perceived complexity. Simple applications can still be
> coded using simple instructions, but more complex requirements can be
> met more simply and efficiently by using some of those "added
> instructions" that seem to lead to complexity.
>
> Complexity is far too often used as an excuse for incompetence or
> laziness; not always or even most of the time, but still far too
> often. You don't let a carpenter into your house if he doesn't know
> how to use his tools, do you????

re:
http://www.garlic.com/~lynn/2007i.html#25 Latest Principles of Operation
http://www.garlic.com/~lynn/2007i.html#26 Latest Principles of Operation

well, i remember the hassle to get compare&swap instruction into the 370
architecture. Charlie had invented compare&swap instruction when he was
working on smp knerel fine-grain locking for cp67 at the science center
http://www.garlic.com/~lynn/subtopic.html#545tech

the "redbook" 370 architecture owners claimed that everybody (namely the
POK favorite son operating system people) thot that test&set was totally
adequate for all multiprocessor support. in order to justify getting
compare&swap instruction into 370 architecture, we had to come up with a
whole boatload of justifications for compare&swap instruction that
wasn't specific to multiprocessor operation. thus was born the stuff in
principle of operations about using compare&swap instruction for
application multithreaded operation (regardless of whether or not it was
multiprocessor environment). lots of past posts mentioning
multiprocessor support and/or compare&swap instruction
http://www.garlic.com/~lynn/subtopic.html#smp

it is sometimes relative. i've claimed that John came up with risc/801
as part of going to the opposite extreme after the extremely complex
future system project failed ... misc. past posts mentioning failed
future system project
http://www.garlic.com/~lynn/subtopic.html#futuresys

and lots of past post mentioning 801, romp, rios, iliad, fort knox,
somerset, power/pc, etc
http://www.garlic.com/~lynn/subtopic.html#801
and old email with 801 references
http://www.garlic.com/~lynn/lhwemail.html#801

Supposedly future system project was a countermeasure to clone
controllers ... something I got (at least partially) blamed for from a
project that I worked on as undergraduate in the 60s producing our own
clone controller
http://www.garlic.com/~lynn/subtopic.html#360pcm

also some "FS" quotes referenced in this post
http://www.garlic.com/~lynn/2007f.html#28 The Perfect Computer - 36 bits?
from article by former executive here 
http://www.ecole.org/Crisis_and_change_1995_1.htm

The FS effort and subsequent failure ... can also be considered as
contributing to the uptake of clone processors (in part because of the
dearth of items in the 370 product pipeline) a few recent posts
http://www.garlic.com/~lynn/2007g.html#55 IBM to the PCM market(the sky is 
falling!!!the sky is falling!!)
http://www.garlic.com/~lynn/2007g.html#57 IBM to the PCM market(the sky is 
falling!!!the sky is falling!!)
http://www.garlic.com/~lynn/2007g.html#59 IBM to the PCM market(the sky is 
falling!!!the sky is falling!!)

and after the failure of the FS project ... there was a rush to get
stuff back into the 370 product pipeline. Recent post attributing that
as big part of the reason that the product group shipped so much of my
code (since I continued to develop 370-based software all thru the FS
activity)
http://www.garlic.com/~lynn/2007i.html#21 John W. Backus, 82, Fortran 
developer, dies

and another recent posting touching on some stuff that went on in the FS era
http://www.garlic.com/~lynn/2007i.html#20 Does anyone know of a documented case 
of VM being penetrated by hackers?
http://www.garlic.com/~lynn/2007i.html#29 Does anyone know of a documented case 
of VM being penetrated by hackers?

another stop-gap effort to try and quickly fill the 370 product pipeline
was 3033x (after failure of FS project) was 303x. The standard processor
development cycle was 7-8yrs ... and they needed to get something out
much quicker than that ... since starting the 370-xa/3081 wouldn't be
out before the early 80s.

So they took they 370/158 microcode engine ... and stripped out the 370
microcode support ... leaving just the integrated channel microcode and
packaged it as the 303x "channel director". Then the 3031 was a 370/158
microcode engine with just the 370 microcode support (and no integrated
channel microcode) paired with a "channel director". The 3032 was a
370/168-3 repackaged to work with "channel director". The 3033 started
out simply being 168 wiring diagram mapped to newer chip technology.
Recent posts about enormous effort to hurry up and get 303x out the
door after failed FS project:
http://www.garlic.com/~lynn/2007d.html#21 How many 36-bit Unix ports in the old 
days?
http://www.garlic.com/~lynn/2007d.html#62 Cycles per ASM instruction
http://www.garlic.com/~lynn/2007e.html#32 I/O in Emulated Mainframes
http://www.garlic.com/~lynn/2007e.html#40 FBA rant
http://www.garlic.com/~lynn/2007f.html#28 The Perfect Computer - 36 bits?
http://www.garlic.com/~lynn/2007f.html#73 Is computer history taught now?
http://www.garlic.com/~lynn/2007g.html#17 The Perfect Computer - 36 bits?
http://www.garlic.com/~lynn/2007g.html#23 The Perfect Computer - 36 bits?
http://www.garlic.com/~lynn/2007g.html#29 The Perfect Computer - 36 bits?
http://www.garlic.com/~lynn/2007g.html#57 IBM to the PCM market(the sky is 
falling!!!the sky is falling!!)
http://www.garlic.com/~lynn/2007h.html#1 21st Century ISA goals?

the other aftermath of the FS project failure was that POK lab convinced
corporate to shutdown the VM development group, decommit the product,
and transfer all the people to POK in order to work on MVS/XA ... also
attempting to shorten the typical development time. Endicott was
eventually able to salvage the product mission and one or two of the
people.

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