[Haskell-cafe] Re: Hardware

[Jon Fairbairn]

"Claus Reinke" <claus.reinke at talk21.com> writes:

> > either be slower than mainstream hardware or would be
> > overtaken by it in a very short space of time.
> 
> i'd like to underline the last of these two points, and i'm
> impressed that you came to that conclusion as early as the
> eighties.

Well, Stuart and I had just been working on TIM, and Thomas
Clarke was one of the folk who built SKIM, so we had a fair
bit of relevant experience between us.  It must have been
between 1986 (when we'd finished TIM) and 1989 (when I got
ill).

> unlike earlier designs, the hardware only leaned toward
> functional, rather than being specific to it (mostly RISC,
> with large register files organised as very fast stack
> windows for a small number of stacks),

We had that sort of thing in mind -- my first implementation
of TIM was on an ARM, so I knew something of what RISC had
to offer.

> and numbers from the hand-configured prototype suggested
> that it would be about twice as fast as contemporary
> standard hardware. which was great, until it became clear
> that, in the time it would have taken to go from that
> prototype to production, the next generation of that
> standard hardware would have been on the market, also
> twice as fast (with the next next generation already on
> its way)..

Yup, that's what we figured (we knew the ARM guys too, and
knowing the rate at which they worked probably helped us see
things quite clearly :-).

> the suggestion that the mainstream might be running out of
> steam along one particular dimension is interesting, but
> in my naive view, there is still the difference between
> any one-shot research project and a snapshot in a
> development pipeline of great momentum

Yes. I think the best bet is to get hold of prototypes and
research fp implementations for them; my TIM implementation
of Ponder must have been the first fp language on ARM, and
the process of doing that probably informed much of the
detailed design of TIM. Doing an fp implementatio for a huge
number of cores strikes me as an exciting avenue.


-- 
Jón Fairbairn                                 Jon.Fairbairn at cl.cam.ac.uk