On Wednesday 02 November 2011, 10:19:08, Eugene Kirpichov wrote:
I forgot to specify my environment.
Windows Server 2008 R2 x64, ghc 7.0.3.
However, I observed the same speed differences on a 64-bit ubuntu with ghc 6.12 - I profiled my application with cairo-trace, and cairo-perf-trace drew in a fraction of a second the picture that my Haskell program spend a dozen seconds drawing.
Just FYI, $ uname -a Linux linux-v7dw.site 2.6.37.6-0.7-desktop #1 SMP PREEMPT 2011-07-21 02:17:24 +0200 x86_64 x86_64 x86_64 GNU/Linux $ g++ -O3 -o csurf surf.cc -I/usr/include/cairo -cairo $ time ./csurf real 0m0.126s user 0m0.119s sys 0m0.006s $ ghc-7.0.4 -O2 hssurf.hs [1 of 1] Compiling Main ( hssurf.hs, hssurf.o ) Linking hssurf ... $ time ./hssurf real 0m5.857s user 0m5.840s sys 0m0.011s $ ghc -O2 hssurf.hs -o hssurf2 [1 of 1] Compiling Main ( hssurf.hs, hssurf.o ) Linking hssurf2 ... $ time ./hssurf2 real 0m0.355s user 0m0.350s sys 0m0.005s (fromRational . toRational) is still slow, but nowhere as slow as it used to be.