[Info-vax] DEC Large Systems

[Scott Dorsey]

Simon Clubley  <clubley at remove_me.eisner.decus.org-Earth.UFP> wrote:
>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 ?

The cpu performance on the vax was very good, but the vax never approached
the performance of the PDP-10 in terms of I/O.  Even after a decade of 
development.  You could put far more users doing routine work on a PDP-10
than on even third generation vaxen.

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

All three are pretty substantially different.

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

No, it was all about maximizing short term profits for shareholders.
--scott
-- 
"C'est un Nagra. C'est suisse, et tres, tres precis."