Re: hmadorf on Lisp vs Fortran

[hmadorf@eso.org]

Dear David,

thanks for replying.

>Integer declarations don't make any difference in most Common Lisps,
>since integers have unlimited range.  Try a fixnum declaration
>if that's what you mean.  Of course, you can't compute 200
>factorial within the fixnum range, and you couldn't compute
>it in Fortran either, since Fortran integers have about the
>same limited range as Lisp fixnums. So I don't know
>what you think this part of your benchmark proves; it doesn't
>seem to have much to do with what you're trying to measure.
Having received your and other people's comments, I don't know 
either. I'll have to repeat the benchmarks using the proper 
declarations, of course.

>It should have been a single-float, double-float,
>short-float, or long-float declaration anyway, since just asking
>for generic float isn't likely to make any difference since the
>compiler wouldn't know which of the four kinds of float you want.
Agreed. T'was basically the first time I inserted declarations, and
boy, did I get it wrong!

>... you should consult >the vendor of that Lisp to find out why 
your program isn't optimized as expected ...
Good point. No time yet. Will do so when returning from trip to the
US. My only fear is that I will have to talk to Franz US directly,
since my experience with German representatives in general (not 
specifically of Franx/Expertise) was not very postive in the past. 

>... should find a Lisp that claims to make
>an effort to give good floating point performance (MCL does not),
>and you should compare against a Fortran with comparable claims
>running on the same machine ...
Agreed. Seems I have to look into CMU-Lisp. I'd love to use MCL,
though, which provides a much nicer development enviroment and,
after all, runs at home, and on PowerBooks and ...

>And if you want to evaluate performance of various languages on
>a CM-5, you should run your tests on a CM-5.
Agreed.

>I would guess that Thinking Machines would be happy to let you run 
>a few tests over the network.
TMI has to fix the *Lisp simulator first. It broke during the
transition to MCL2.0. Do you have any contacts at TMI?

Cheers
Hans-Martin