On Dec 7, 2010, at 1:58 PM, Konrad Hinsen wrote: > Somewhat by accident I noticed an enormous speed difference in basic NumPy > operations between my MacPorts installation (py26-numpy) and the NumPy 1.5.1 > binaries from the NumPy sourceforge site used with MacPython 2.6, also > downloaded as a binary. > > ~/projects/solar_system> /usr/local/bin/python bench2.py > CPU time: 16 s > ~/projects/solar_system> /opt/local/bin/python bench2.py > CPU time: 45 s > > The script bench2.py is attached. I wonder what could cause this big > difference. No BLAS operations are used, so the difference in BLAS > implementation should not matter. In fact, all that happens is allocation of > a big array and lots of float subtractions. > > Did anyone look into this already? > > Konrad. > > <bench2.py>
Wow, interesting result. I just ran the benchmark on my Mac Pro 2008 and got 44 s with py26-numpy. I rebuilt it just to take a look. I noticed it is using -O3 in the configure flags which is good, but it was using gcc-4.2 to build. I have the gcc44 variant selected and that is the default, so it's possible that is the problem but maybe I'm just misunderstanding the gcc4x variants. Cheers! Frank _______________________________________________ macports-users mailing list [email protected] http://lists.macosforge.org/mailman/listinfo.cgi/macports-users
