Shaheen II supports three different programming environments with Cray, Intel and GNU compilers. Below, you will find useful information on compilers.
- For C code
|
Compiler Options for MPI/Serial code |
Compiler Options for OpenMP code |
Compiler manual page |
|
|
PrgEnv-cray |
cc -o exe code.c |
cc -o exe -h omp code_mp.c |
man craycc |
|
PrgEnv-intel |
cc -o exe code.c |
cc -o exe -openmp code_mp.c |
man icc |
|
PrgEnv-gnu |
cc -o exe code.c |
cc -o exe -fopenmp code_mp.c |
man gcc |
- For C++
|
Compiler Options for MPI/Serial code |
Compiler Options for OpenMP code |
Compiler manual page |
|
|
PrgEnv-cray |
CC -o exe code.cpp |
CC -o exe -h omp code_mp.cpp |
man crayCC |
|
PrgEnv-intel |
CC -o exe code.cpp |
CC -o exe -openmp code_mp.cpp |
man icpc |
|
PrgEnv-gnu |
CC -o exe code.cpp |
CC -o exe -fopenmp code_mp.cpp |
man g++ |
- For C and C++
Once you have validated the accuracy of your code, it may be worth trying a more aggressive set of options to improve performance. Compiler warnings can help you to identify errors at compile time, and full optimisation can introduce problems in some code. Therefore, verification should be done for each tested optimisation flag. Here are some suggestions:
|
Options to generate warnings |
To generate run time checks |
For optimisation |
|
|
PrgEnv-cray |
-h msglevel_3 |
-h bounds |
-O3 -hfp3 |
|
PrgEnv-intel |
-w2 |
-check=stack |
-O2 -ipo |
|
PrgEnv-gnu |
-Wall |
-fbounds-check |
-O3 -ffast-math -funroll-loops |
- For Fortran
|
Compiler Options for MPI/Serial code |
Compiler Options for OpenMP code |
Compiler manual page |
|
|
PrgEnv-cray |
ftn -o exe code.f90 |
ftn -o exe -h omp code_mp.f90 |
man crayftn |
|
PrgEnv-intel |
ftn -o exe code.f90 |
ftn -o exe -openmp code_mp.f90 |
man ifortran |
|
PrgEnv-gnu |
ftn -o exe code.f90 |
ftn -o exe -fopenmp code_mp.f90 |
man gfortan |
|
Options to generate warnings |
To generate run time checks |
For optimisation |
|
|
PrgEnv-cray |
-m 3 |
-Rbcps |
-O3 -hfp3 |
|
PrgEnv-intel |
-warn all |
-check all |
-O2 -ipo |
|
PrgEnv-gnu |
-Wall |
-fcheck=bounds |
-O3 -ffast-math -funroll-loops |