[Haskell-cafe] Known Unknowns

Chris Kuklewicz haskell at list.mightyreason.com
Thu Feb 2 15:28:39 EST 2006


Joel Koerwer wrote:
> Don, that's a great little mini tutorial, exactly what I was hoping for.
> I'm looking forward to learning more tricks.
> 
> On an unrelated note, I have an STUArray nbody. I haven't really looked
> closely at the chris+dons version, but I suspect they amount to doing
> the same thing. I get commensurate runtimes at least. But I'll post it
> on the wiki in a while in case there is some optimization I missed.
> 
> On an even more unrelated note, I get slower runtimes with -optc-O3 and
> -optc-ffast-math than without. Individually or in tandem. Odd. This is
> ghc 6.4.1 and gcc 4.0.3 on a (Banias) Pentium M.

More architecture benchmarking:

On a powerbook G4, Joel Koerwer's entry on http://haskell.org/hawiki/NbodyEntry
runs faster than dons+chris.

And I edited it to make it smaller, but by hoisting 'size' and 'dt' I also made
it run quite a bit faster.  It now takes 1.7x less time than dons+chris.

Don, could you check the speed on your architecture?

-- 
Chris


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