[email protected] (Joel C. Ewing) writes:
> No (about the "free", not about the "dead for decades"), DOS/VS was the
> last really free base (last version Release 34?).   Perhaps technically
> DOS/VSE was "free", as there didn't appear to be a monthly licensing
> charge for DOS/VSE itself (Computerworld, April 30, 1979, p4), but in
> the practical sense a production DOS/VSE system was definitely not free
> as there were monthly support charges for DOS/VSE and separate monthly
> licensing plus support charges for must-have VSE add-on components like
> VSE/Power and others.  DOS/VSE came out with the IBM 4331 & 4341
> processors in 1979 and supported running in both S/370 mode or the
> ECPS:VSE mode supported by the 4300 processor family.

various legal actions resulted in 23June1969 unbundling announcement
where (application) software & other stuff started to be charged for
(however they made the case the kernel software should still be free).
some past posts
http://www.garlic.com/~lynn/submain.html#unbundle

during future system effort 370 efforts were being killed off (lack of
370 products there era is credited with clone processors market
foothold). after future system failed ... past posts
http://www.garlic.com/~lynn/submain.html#futuresys

there was mad rush to get stuff back into 370 product pipeline.
POK kick off 3033 (168 logic mapped to faster chips) and
3081/XA in parallel ... reference
http://www.jfsowa.com/computer/memo125.htm
 
XA had a lot of extensions tailored for MVS.

Endicott did something similar for e-architecture (4331 & 4341) tailored
for vs1&dos. In large part a single virtual address space supported as
part of the hardware architecture. Rather than having segment & page
tables ... there were two new instructions that told the machine what
virtual address was at what real address ... and invalidated the virtual
address.

However there was an enormous explosion in vm/4300 sales (before
announce, 4341s were referred to a "E4") ... which required multiple
virtual address space ... which met that large number of 4300s ran in
370 mode rather than e-mode. Note that POK had convinced corporate to
kill off the vm370 product and move all the development people to POK as
part of MVS/XA development (including excuse that MVS/XA would ship on
time, if they couldn't get the additional resources). Endicott manage to
save the vm370 product mission, but had to reconstitute a development
group from scratch. some old 4300 related email
http://www.garlic.com/~lynn/lhwemail.html#43xx

Note that VS1 and VM/370 "ECPS" was different than e-machine
architecture. It originated with the 138/148 (virgil/tully) ...  where
selected high use kernel/system instructions paths were implemented in
microcode. The low & mid-range machine were vertical microcode machines
with an avg of 10 native instructions per 370 instruction (somewhat
analogous to mainframe emulators that run on Intel platforms). Kernel
instruction paths tended to get 10:1 performance improvement when moved
to microcode. I did the initial study and effort for the VM/370 ECPS
... old post with results for selecting pathlengths to be moved to
microcode (I was told, that I needed to select the 6kbytes of highest
executed kernel, which turned out to account of 80% of vm/370 kernel
execution)
http://www.garlic.com/~lynn/94.html#21 370 ECPS VM microcode assist

trivia ... the methodology for selecting the VS1 paths wasn't nearly so
rigorous.

other trivia ... major motivation for Future System product was as
countermeasure to clone controllers ... but the (failed) Future System
effort contributed significantly to the rise of the clone processors.
The threat of clone processors resulted in decision to transition to
charging for system/kernel software. I continued to work on 370 stuff
all during the FS period ... even periodically ridiculing FS stuff
... which wasn't exactly career enhancing. Also one of my hobbies was
developing&supporting advanced enhanced operating systems for internal
datacenters ... 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

In any case, the mad rush to get stuff back into 370 product pipeline
contributed to decision to pick up various of my stuff and ship it in
products for customers. One part of that stuff (dynamic adaptive
resource manager) was selected to be guinea pig for starting to charge
for system/kernel software ... and I had to spend some amount of time
with lawyers & business types going over policies for system/kernel
software charging.

even more trivia: when 3033 looked at doing something similar to ECPS
... it didn't work out as well. 3033 was horizontal microcode machine
that had been optimized so it was executing nearly one 370 instruction
per machine cycle. Directly dropping system/kernel 370 pathlengths into
microcode could even result in running slower than the original 370.

-- 
virtualization experience starting Jan1968, online at home since Mar1970

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN

Reply via email to