[Haskell-cafe] Haskell performance question

[Don Stewart]

dpiponi:
> On Nov 8, 2007 11:34 AM, Jason Dusek <jason.dusek at gmail.com> wrote:
> > Can you show us your compilation options and timings?
> 
> I was simply using -O3. I tried a bunch of other flags (copied from
> the shootout examples) but they made no appreciable difference.

Argh, -O2 please. -O3 does nothing more, and sometime does less,
depending on the compiler :)

Double math always needs the gcc backend, and -optc flags (see the
spectral-norm post).

> 
> I was getting about 1.5s for the Haskell program and about 0.08s for
> the C one with the same n=10,000,000.

I'm sure we can do better than that!
  
> I now see that my ghc is in fact an i386 build whose binary was
> downloaded from the ghc binary web page. So I'm going to try to make a
> better comparison with a 64 bit 6.8.1. The batteries on my laptop will
> probably drop to zero before then however, so it'll be tomorrow at the
> earliest.

If you can post the code somewhere, that would be great, with examples
of how to reproduce your timings.

-- don