Hi, I am using gfortran for molecular dynamics code and recently installed 11.1 at Fedora 13.
# ifort --version
ifort (IFORT) 11.1 20100414
Copyright (C) 1985-2010 Intel Corporation. All rights reserved.
1. When I installed, it didn't recognize the OS. May intel fortran not suport Fedora 13 fully yet?
2. Anyway, I completed install and compiler seems working - even though sometims there is a problem with "-fast (actually -ipo)",
complaining ld cannot find libraries.
3. I found that the compiler may yield slower result than gfortran. I am using
> gfortran -march=native -ffast-math -funroll-loops -O3
> ifort -O3 -m64 -ipo -no-prec-div
Computer has Intel Xeon CPU W3680 @ 3.33GHz.
Even though performance is very dependent on the code/optimization, the result is quite weird to me. Mostly my code shows 30% better performance with ifort, compared to gfortran. Therefore, I would like to know if there is something I can do for better performance/optimization. Or Fedora13 is not ready for ifort? Any comment will be appreciated.