Thank you all! @Beliavsky @urbanjost @themos @R_cubed @han190 .
Here is the code,
Very easy, a very small code (many lines are commented actually). On windows, if you installed gfortran and make, then you just need to download the files in one folder, then do
make
then run
rpem.exe
If I use Intel Fortran on windows, it took 0.5s, gfortran tool 3s.
On Ubuntu both intel and gfortran took 0.5s.
I tried to use gprof on windows with gfortran, but it always give me empty out file.
I always find on Ubuntu, gfortran’s performance is similar with Intel Fortran.
But on windows, gfortran, at least for my code, is basically always several times slower than intel Fortran. If someone have the interest to have a quick look and identify the issue it will be greatly appreciated!
By the way, does anyone else have similar issue?
ie, the same code, using gfortran on windows it is several times slower than using gfortran on Ubuntu.
Thanks much!