Re: Using Ada for device drivers? (Was: the Ada mandate, and why it collapsed and died)

[Dr Chaos <mbkennelSPAMBEGONE@NOSPAMyahoo.com>]

On Fri, 9 May 2003 09:30:26 +0100, Tom Welsh <news@tom-welsh.co.uk> wrote:
> 
> I can confirm that, when I was working at DEC in the 1980s, we saw Unix
> first of all as a nuisance, then a threat, and finally as a scourge. The
> reason was its low cost.
> 
> As of about 1981-2, a few of our customer showed up using Unix. At the
> time I was working in the UK Remote Diagnosis Centre, where we could run
> automated tests on remote computers - basically letting our computers
> interrogate the diagnostic consoles. The leading edge of our efforts was
> in looking at the operating system and using it, as well as hardware
> registers, to diagnose problems that could be either hardware or
> software. I remember being able to tell a field service tech, when he
> arrived on site, which fuse to replace in which magtape drive to stop
> the whole system from hanging (bad design, I agree).
> 
> All of this broke down with Unix, because we weren't trained on it and
> had no clue how it worked. (Also, its troubleshooting features at that
> time were rudimentary compared to VMS).
> 
> It was annoying to us that more and more customers - starting with
> universities and other research organisations that couldn't afford our
> usual "corporate" rates - were taking up Unix. VMS was designed
> simultaneously with the VAX architecture, and they had a lot of synergy.
> Unix threw a lot of that away, from our point of view.

Yes that's right.  To a large degree, that was the entire point, and
the attraction.

Nobody cared about the Vax architecture that much.  

I remember academic computing at that time.  People liked the
reliability of the VMS compilers.  Everything else about VMS seemed
constraining and plodding.

Here is one key example.  VMS didn't have a shell where actual
ordinary users could write programs which functioned like the built in
ones.  It was "RUN MY_USER_PROGRAM" versus the huge hairball of "SHOW
THIS/THAT" or "SET THIS TO THAT".

If you wanted to have your own software work like that it was a huge
rigamarole poring through one of the 20 or 30 orange covered
notebooks.

Unix had argc and argv, and a simple library that you didn't even
need to use if you didn't want to.

It was like Alexander cutting the Gordian knot. 

DCL was completely cognitively opaque.  What exactly was it doing, what
programs is it running when?

Unix was dumb, and smart at the same time.

Simply: 

      Unix *felt* like freedom.  
      VMS didn't.

> What we didn't understand was that, from the users' point of view, Unix
> gave them 80 percent (at least) of the benefits for 20 percent (at most)
> of the cost.

It was more than that.  It was fast.  

I knew it was over for DEC the first day the lab I worked in got a Sun
3/260 (?) with a bitmapped terminal, as opposed to the serial
VT220/240's going into the VAX.  The difference was huge: you type
"DIR" and you watch as the system emitted the listing of files, line
by line.  About 15 seconds to complete.  On the Sun, one 'ls' and the
entire home directory listing just *appeared* the moment the return
key returned.

And then when the first MIPS and SPARCs offered an enormous 4-5x VAX
performance at a very much lower cost it was over.

The VAX microstations were pathetic next to their competing Sun 4's. 

> Later DEC executives (a remarkable number of whom now work for
> Microsoft) thought up a new line, which went something like this. Unix
> is OK if all you want is a basic LCD OS. But VMS will always have the
> really valuable extras that help give you competitive differentiation
> (Michael Porter came along just in time for them to grab that straw).
> So, for the extra cost, VMS keeps you 2-3 years ahead of the curve.

> Heard something similar to that lately?

Yeah.  The difference was that DEC was profoundly misguided but ethical,
and DEC never had a substantial monopoly.  

Microsoft has taken the lesson of the IBM anti-trust trial to heart: NEVER
give in to anything.

> -- 
> Tom Welsh