Very poor Lisp performance - comp.lang.lisp

Message from discussion Very poor Lisp performance
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Date: Fri, 12 Aug 2005 20:58:09 -0700
From: M Jared Finder <ja...@hpalace.com>
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Subject: Re: Very poor Lisp performance
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Jon Harrop wrote:
> Several people have kindly ported my ray tracer from this page:
> 
>   http://www.ffconsultancy.com/free/ray_tracer/languages.html
> 
> to Lisp. Some of them are reporting competitive performance. However, when I
> try to run their programs with either CMUCL or SBCL they are two orders of
> magnitude slower. Given the number of people claiming similarly good
> performance, I'd like to know what the possible cause of the relative
> slowdown on my computer is?
> 
> My system is an unladen 900MHz Athlon T-bird with 768Mb RAM running Debian
> testing with SBCL 0.8.16 and CMUCL "19b-release-20050628-3 + minimal debian
> patches". Other people have both slower and faster CPUs and more and less
> RAM but all are consistently much faster than mine.
> 
> I believe SBCL always compiles to native code and I am asking CMUCL to
> compile to native code with:
> 
> (compile-file "ray4.lisp")
> (load "ray4.x86f")
> (time (main 6.0 "image.pgm" 256.0 4.0))
> 
> Any ideas?

Post the ported code and we can take a look at it.  Without the code, we 
can only make shots in the dark.

   -- MJF