Alan Altmark wrote:
Well, it's been nigh on 40 years that CMS has been around.  Seems like a
committment to me.  CMS is here to stay.  If all the people with z/OS
get z/VM and [re]discover CMS, who knows what might happen?  "Never say
die!"

re:
http://www.garlic.com/~lynn/2007j.html#41 z/VM usability

well, cms (as in cambridge monitor system) started on cp40 (cambridge had
gotten a 360/40 and did the hardware modifications to implement virtual
memory ... pending getting 360/67) ...  cambridge then got 360/67 and
morphed cp40 into cp67 ... so it has been 40yrs (in part, CMS work
could even start on real 360/40 before cp40 was operational)

from Melinda's history
http://www.princeton.edu/~melinda/

By September of 1965, file system commands and macros already looked
much like those we are familiar with today: ``RDBUF'', ``WRBUF'',
``FINIS'', ``STATE'', etc

... snip ...

cambridge installed cp67 out at lincoln labs in 1967 and then last week
in jan68 came out to install cp67 at the univ where i was undergraduate.
Note, that in jan68, the cp67 people were still apprehensive about CMS
filesystem ... with cp67 source, assemble, and build still being done on
os/360 (keeping cp67 kernel build TXT files in card tray and modify/assemble
routine, punch new TXT file, update that file in the card tray and rebuild
kernel by doing IPL of real cards).

in the morph of cp67 to vm370 ... they changed the cms name to
conversational monitor system.

major change in cms from cp67 to vm370 was a little re-arranging of cms
kernel in anticipation of 370 (r/o) segment protection. However, in
doing the virtual memory hardware retrofit to 370/165 ... they ran into
problem with schedule slipping. In order to regain six months in the
schedule for 370/165 virtual memory, they dropped r/o segment protect
and some number of other features from the original 370 virtual memory
architecture (and to have compatibility across the 370 product line
... the same features had to also be removed from other 370 models that
already had implemented the full 370 virtual memory architecture).  With
370 hardware r/o segment protect dropped ... vm370 had to revert to the
page protect hack used by cp67 that involved fiddling the 360 storage
protect keys.

Then during the "future system" period ... much of the corporation was
distracted and a lot of 370 product activity fell by the way side.
Misc. past posts about future system:
http://www.garlic.com/~lynn/subtopic.html#futuresys

I had made some unflattering comments about practicallity of future
system stuff and continued to do both cp67 and cms enhancements ...  and
then ported them from cp67 to vm370 ... some old email
http://www.garlic.com/~lynn/2006v.html#email731212
http://www.garlic.com/~lynn/2006w.html#email750102
http://www.garlic.com/~lynn/2006w.html#email750430

after FS was canceled, there was rush to get stuff back into 370 product
pipeline. Part of this was reason that small subset of the "virtual
memory management" enhancements ...  a lot of shared segment stuff
http://www.garlic.com/~lynn/subtopic.html#adcon
that had been integrated with the paged mapped filesystem stuff
http://www.garlic.com/~lynn/subtopic.html#mmap

was released as DCSS in vm370 release 3.

Canceling FS contributed to enabling me to also release the resource
manager (that included a lot of changes that were in cp67 that i had
done ...  which were dropped in the morph from cp67 to vm370)
http://www.garlic.com/~lynn/subtopic.html#fairshare
http://www.garlic.com/~lynn/subtopic.html#wsclock

It was also in the aftermath of killing FS that POK convinced the
corporation to kill the vm370 product, shutdown the vm370 product group
and move all the people to POK to help accelerate the mvs/xa development
schedule (again attempting to make up lost time in 370 product pipeline
resulting from the FS distraction). Eventually Endicott was able to
salvage the vm370 product mission.

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