Post by undefined Hancock-4
I don't have my S/360 history handy, but wasn't a foundation to these
problems the focus on Future System instead of upgrading System/360?
If I recall correctly, they suddenly realized FS wasn't gonna work and S/360
was obsolete so they rushed out S/360 with some improvements, but not
a lot. First was the S/3x5 series, then later the improved S/3x8 series
which I think was a lot better.
motivation for 370/165 (and all other 370s) to virtual memory took hold
before FS took over the company. Initial OS/VS2 release 1 was SVS ...
little different from running MVT in a CP67 16mbyte virtual machine
... except MVT built the virtual address table and was able to do page
faults (but not efficiently or optimized, since they expected little or
no page faults) ... biggest issue was fitting CP67 CCWTRANS into
EXCP/SVC0 channel program processing ... which created a copy of the
passed channel program replacing CCW virtual addresses with real.
part of discussion from archived post (from bit.listserv.ibm-man, could
also be found in the google newsgroup archives)
Of course, the estimates for OS/VS were based on a misperception. The
Kingston estimate for OS/VS2 Release 1 (SVS) had an estimate for the
work needed for Release 2 (MVS), but it was couched as release 1 cost
plus a delta - in other words, the same cost as release 1 plus some
more. Since the Kingston resources were being redeployed to FS, that
meant that there weren't going to be enough people to do both. Since MVS
was supposed to be the glide path for FS (which would be OS/VS2 Release
3), this was unwelcome news. xxxxx and yyyyy modified the plan to reuse
some of the SVS resources plus people transitioning from OS/360. Bob
Evans did his part by cutting a year off the MVS development schedule.
... snip ...
I continued to work on 360/370 all through the FS period ... even
periodically ridiculing what they were doing, which wasn't exactly a
career enhancing activity (lot of stuff was never really worked
out ... just pie-in-the-sky waving hands).
long winded discussion of FS ... including when it finally imploded,
quick&dirty 3033 and 3081 efforts were kicked off in parallel
Note that 370 virtual memory architecture had a whole bunch of features
... however the 165 hardware people complained that if they had to
implement all the architecture features ... it would delay virtual
memory announce by six months ... as a result features were dropped to
get 370/165 virtual memory back on schedule ... and other platforms that
had already implemented the full architecture had to remove the dropped
features and any software developed that used the dropped features had
to be rewritten.
Future System disaster in the 70s ... from Ferguson & Morris,
"Computer Wars: The Post-IBM World", Time Books, 1993 .... reference
to the "Future System" project 1st half of the 70s:
... and perhaps most damaging, the old culture under Watson Snr and Jr
of free and vigorous debate was replaced with *SYNCOPHANCY* and *MAKE
NO WAVES* under Opel and Akers. It's claimed that thereafter, IBM
lived in the shadow of defeat
... snip ...
Major motivation for Future System was clone controllers ... an
objective was to make the interfaces so complex that the clone makers
wouldn't be able to follow ... some folklore was that 37x5
telecommuncation box was one of the few that tried to still meet the FS
objective (with VTAM & NCP).
Note, during FS, internal politics were shutting down 370 projects
... and the lack of new 370 products during the FS period is credited
with giving the clone processor makers (like Amdahl) their market
foothold (effort to thwart clone controllers enabled clone processor
clone trivia: At the univ. I had taken a two semestor hr intro to
fortran/computers ... then within a year, univ. hires me fulltime to be
responsible for ibm mainframe system (306/67, but ran as 360/65 with
os/360). Then three people from science center came out in jan1968 and
installed cp67 and univ. let me play with it on weekends. Original
terminal support had 2741 & 1052 terminal support with automagic
terminal type identification. Univ. had tty 33s and a 35 ... so I added
tty/ascii terminal support and extended automagic terminal type support
to tty/ascii. I then wanted to have single dialin phone number for
al terminals ... single "hunt group"
didn't quite work ... IBM took shortcut in the terminal controller, why
it was possible to change the terminal type port interface with the SAD
CCW ... couldn't change the line speed (aka work for leased lines).
This help prompt the univ. to do a clone controller project ... build a
channel interface board for a Interdata/3 programmed to emulate a ibm
telecommuncation controller ... with the addition of being able of doing
dynamic line speed determination. This was then updated with an
Interdata/4 for the channel interface and clusters of Interdata/3
handling the ports. Interdata starts selling it as a clone controller
and four of us get written up (for some part of) IBM clone controller
business. Perkin-Elmer buys Interdata and continues to sell the box under
their own logo.
virtualization experience starting Jan1968, online at home since Mar1970