[Info-vax] DEC Large Systems

[Simon Clubley]

On 2019-06-27, m. thompson <michael.99.thompson at gmail.com> wrote:
> On Thursday, June 27, 2019 at 7:50:51 AM UTC-4, Bill Gunshannon wrote:
>> Another question born out of curiosity.
>> 
>> I was looking at a catalog called Large Systems Software
>> Referral Catalog (Fourth Edition) from 1984.
>> 
>> It lists DECsystem-10, DECSYSTEM-20 and VAX. (notice the
>> curious spellings used by DEC themselves  :-)
>> 
>> What exactly did the VAX offer or what shortcomings were
>> seen in the 10 and 20 that caused VAX to become the hero
>> and the other large systems to go away?
>> 
>> bill
>
> There was no good technical reason to kill the development of the next generation of the PDP-10 in favor of the VAX. This was purely a marketing and product management decision.

What about the reported problems with Jupiter ?

Was the PDP-10 architecture capable of growing to the performance levels
that VAX did ? Did DEC simply need a new, and 32-bit, architecture to
match what others were starting to do at the time ?

How does the functionality and general architecture of VMS compare to
that of TOPS-10/TOPS-20 ?

IOW, had TOPS-10/TOPS-20 simply reached the end of the road and
therefore it was time for a new OS architecture ?

If TOPS-10/TOPS-20 and the PDP-10 had carried on to (say) 1985,
instead of VAX and VMS, where would DEC have been compared to where
they were with VAX ?

Don't forget that by the middle 1980s, DEC were already talking about
the generation after VAX.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world