[Info-vax] VMS internals design, was: Re: BASIC and AST routines

[Clair Grant]

On Friday, November 26, 2021 at 6:40:42 AM UTC-5, felim... at gmail.com wrote:
> On Thursday, 25 November 2021 at 15:48:37 UTC, Dave Froble wrote: 
> > VMS was designed and implemented for VAX, not generic computers.
> As I remember it, VAX/VMS was designed by DEC to be its best ever OS then the VAX hardware was designed and built to run it not the other way around. There were probably some mistakes made, unforeseen implementation issues and some miscommunications during parallel development of the hardware and software but the facilities that this combination provided, especially in comparison to the price range of other systems at the time, was revolutionary. 
> 
> OpenVMS is not proprietary in the traditional sense but it is difficult to port to hardware that was not designed to run it. It is certainly worth tidying up the legacy flaws to make future ports easier but, until somebody designs new hardware that can utilise / exploit the full functionality of OpenVMS, any port will be difficult, incomplete and imperfect.

Have not been here for a bit. My answer to the "how many people" question.......

If you include the compiler teams who were actually separate from VMS Engineering itself in the bad old days, there was somewhere in the range of 250 people in the two organizations combined when we ported from VAX to Alpha and then Alpha to IPF. Not all of these people worked on the port all at once but they were all available to pitch in as needed even when it was not their full-time job. Both of those ports took 3 years; they were very different technically but nonetheless, the total elapsed time was eerily the same.

With the same person power, porting to x86 would have been roughly the same, I believe. No reason to think otherwise (similar issues, same parts of the system needing architecture-specific work). But that is not the case. We have way fewer people now so it is not surprising to me, at least, that it is taking way longer.

Clair

BTW: Right after we ported to IPF, I was asked how long it would take to port VMS to x86. I said, 3 years, given the same of team that just completed porting. I never heard another word about that topic.