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Compiling code

author: Jan Zabloudil

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Compiling code

CPU architectures Skylake and Cascadelake:

These architectures are available in the following nodes/partitions:

  • VSC-4 Login nodes l4[0-9]
  • skylake_0096
  • skylake_0384
  • skylake_0768
  • cascadelake_0384

You can choose between these compilers:

  • Intel
  • GNU

Usually on these architectures the Intel compiler delivers the best performance.

Compiling code

CPU architectures Zen2 and Zen3:

These architectures are available in the following nodes/partitions:

  • VSC-5 Login nodes l5[0-6]
  • zen3_0512
  • zen3_1024
  • zen3_2048
  • gpu_a100_dual
  • zen2_0256_a40x2

You can choose between these compilers:

  • Intel
  • GNU
  • AOCC

Usually on these architectures the AOCC compiler delivers the best performance.

Compiling code

Skylake environment

Modules:

Intel compilers:

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(skylake) [VSC-4]$ module load intel/19
(skylake) [VSC-4]$ module load compiler/latest

GNU compilers:

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(skylake) [VSC-4]$ module load gcc/12.2.0-gcc-8.5.0-aal4zp2
(skylake) [VSC-4]$ module load gcc/9.1.0-gcc-8.5.0-mj7s6dg

Compiling code

Zen3 environment

Modules:

Intel compilers:

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(zen3) [VSC-5]$ module load intel/19
(zen3) [VSC-5]$ module load compiler/latest

GNU compilers:

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(zen3) [VSC-5]$ module load gcc/11.2.0-gcc-11.2.0-5i4t2bo
(zen3) [VSC-5]$ module load gcc/10.3.0-gcc-11.2.0-3k4sof7

AOCC compiler:

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(zen3) [VSC-5]$ module load aocc/3.2.0-gcc-11.2.0-y53mdzy

Compiling code

Compiler names

Intel:

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icc       # C compiler
icpc      # C++ compiler
ifort     # Fortran compiler

GNU:

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gcc       # C compiler
g++/c++   # C++ compiler
gfortran  # Fortran compiler

AOCC:

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clang     # C compiler
clang++   # C++ compiler
flang     # Fortran compiler

Compiling code

Examples: compiling serial code

  • Compiler: Intel
  • Language: C
  • ~training/examples/15_compiling/hello.c
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(skylake/zen3) [VSC-4/5]$ module load compiler/latest

Compile without optimization:

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(skylake/zen3) [VSC-4/5]$ icc -O0 hello.c -o hello_c
(skylake/zen3) [VSC-4/5]$ ./hello_c
Hello World

Compile with optimization:

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(skylake/zen3) [VSC-4/5]$ icc -O3 -xHost hello.c -o hello_c
(skylake/zen3) [VSC-4/5]$ ./hello_c
Hello World

Compiling code

Examples: compiling serial code

  • Compiler: GNU
  • Language: C
  • ~training/examples/15_compiling/hello.c
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(skylake) [VSC-4]$ module load gcc/12.2.0-gcc-8.5.0-aal4zp2
(zen3) [VSC-5]$ module load gcc/11.2.0-gcc-11.2.0-5i4t2bo

Compile without optimization:

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(skylake/zen3) [VSC-4/5]$ gcc -O0 hello.c -o hello_c
(skylake/zen3) [VSC-4/5]$ ./hello_c
Hello World

Compiling code

Examples: compiling serial code

  • Compiler: GNU
  • Language: C
  • ~training/examples/15_compiling/hello.c

Compile with optimization:

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(skylake) [VSC-4]$ gcc -O2 -march=skylake hello.c -o hello_c
(zen3) [VSC-5]$ gcc -O2 -march=znver3 hello.c -o hello_c
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(skylake/zen3) [VSC-4/5]$ ./hello_c
Hello World

Compiling code

Examples: compiling serial code

  • Compiler: AOCC
  • Language: C
  • ~training/examples/15_compiling/hello.c
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(zen3) [VSC-5]$ module load aocc/3.2.0-gcc-11.2.0-y53mdzy

Compile without optimization:

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(zen3) [VSC-5]$ clang -O0 hello.c -o hello_c
(zen3) [VSC-5]$ ./hello_c
Hello World

Compiling code

Examples: compiling serial code

  • Compiler: AOCC
  • Language: C
  • ~training/examples/15_compiling/hello.c

Compile with optimization:

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(zen3) [VSC-5]$ clang -O3 -march=znver3 hello.c -o hello_c
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(zen3) [VSC-5]$ ./hello_c
Hello World

Compiling code

Examples: compiling OPENMP code:

  • Compiler: Intel
  • Language: C
  • ~training/examples/15_compiling/hello-openmp.c
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(skylake/zen3) [VSC-4/5]$ icc -qopenmp hello_openmp.c -o hello_openmp_c
(skylake/zen3) [VSC-4/5]$ export OMP_NUM_THREADS=2
(skylake/zen3) [VSC-4/5]$ ./hello_openmp_c
Hello World... from thread = 0
Hello World... from thread = 1

Compiling code

Examples: compiling OPENMP code:

  • Compiler: GNU
  • Language: C
  • ~training/examples/15_compiling/hello_openmp.c
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(skylake/zen3) [VSC-4/5]$ gcc -fopenmp hello_openmp.c -o hello_openmp_c
(skylake/zen3) [VSC-4/5]$ export OMP_NUM_THREADS=2
(skylake/zen3) [VSC-4/5]$ ./hello_openmp_c
Hello World... from thread = 0
Hello World... from thread = 1

Compiling code

Examples: compiling OPENMP code:

  • Compiler: AOCC
  • Language: C
  • ~training/examples/15_compiling/hello_openmp.c
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(skylake/zen3) [VSC-4/5]$ clang -fopenmp hello_openmp.c hello_openmp_c
(skylake/zen3) [VSC-4/5]$ export OMP_NUM_THREADS=2
(skylake/zen3) [VSC-4/5]$ ./hello_openmp_c
Hello World... from thread = 0
Hello World... from thread = 1

Compiling code

Compiling MPI code:

  • Use compiler wrappers
  • Various MPI implementations available:
  • Intel MPI
  • OpenMPI

Compiling code

Compiling MPI code: Intel MPI

Compiler wrappers for Intel compiler:

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mpiicc              # C
mpiicpc             # C++
mpiifort            # Fortran

Compiler wrappers for GNU compiler:

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mpicc/mpigcc        # C
mpicxx/mpigxx       # C++
mpif90/mpif77/mpifc # Fortran

Compiling code

Compiling MPI code: Intel MPI

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(skylake) [VSC-4]$ module purge
(skylake) [VSC-4]$ module load compiler/latest intel-oneapi-mpi/2021.6.0-intel-2021.5.0-wpt4y32
(skylake) [VSC-4]$ mpiicc -show
(skylake) [VSC-4]$ module purge
(skylake) [VSC-4]$ module load gcc/12.2.0-gcc-8.5.0-aal4zp2 intel-oneapi-mpi/2021.6.0-intel-2021.5.0-wpt4y32
(skylake) [VSC-4]$ mpicc -show

Compiling code

Compiling MPI code: OpenMPI

Compiler specific installations, e.g.:

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(skylake) [VSC-4]$ module load openmpi/4.1.4-intel-19.1.3.304-6xqnw75
(skylake) [VSC-4]$ module load openmpi/4.1.4-gcc-12.2.0-owirnm6
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(zen3) [VSC-5]$ module load openmpi/4.1.4-gcc-11.2.0-ub765vm
(zen3) [VSC-5]$ module load openmpi/4.1.4-aocc-3.2.0-7abidzt

Compiler wrappers:

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mpicc                    # C
mpic++/mpiCC/mpicxx      # C++
mpif77/mpif90/mpifort    # Fortran

Compiling code

Examples: compiling MPI code

  • Compiler: Intel
  • MPI: Intel
  • Language: C
  • ~training/examples/15_compiling/hello_mpi.c
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(skylake) [VSC-4]$ module purge
(skylake) [VSC-4]$ module load compiler/latest intel-oneapi-mpi/2021.6.0-intel-2021.5.0-wpt4y32

Compile without optimization:

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(skylake) [VSC-4]$ mpiicc -O0 hello-mpi.c -o hello-mpi_c
(skylake) [VSC-4]$ mpirun -np 2 ./hello-mpi_c
Hello world from processor l44, rank 1 out of 2 processors
Hello world from processor l44, rank 0 out of 2 processors

Compiling code

Examples: compiling MPI code

  • Compiler: Intel
  • MPI: Intel
  • Language: C
  • ~training/examples/15_compiling/hello_mpi.c
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(skylake) [VSC-4]$ module purge
(skylake) [VSC-4]$ module load compiler/latest intel-oneapi-mpi/2021.6.0-intel-2021.5.0-wpt4y32

Compile with optimization:

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(skylake) [VSC-4]$ mpiicc -O3 -xHost hello-mpi.c -o hello-mpi_c
(skylake) [VSC-4]$ mpirun -np 2 ./hello-mpi_c
Hello world from processor l44, rank 1 out of 2 processors
Hello world from processor l44, rank 0 out of 2 processors

Compiling code

Examples: compiling MPI code

  • Compiler: GNU
  • MPI: Intel
  • Language: C
  • ~training/examples/15_compiling/hello_mpi.c
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(skylake) [VSC-4]$ module purge
(skylake) [VSC-4]$ module load gcc/12.2.0-gcc-8.5.0-aal4zp2 intel-oneapi-mpi/2021.6.0-intel-2021.5.0-wpt4y32

Compile without optimization:

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(skylake) [VSC-4]$ mpicc -O0 hello-mpi.c -o hello-mpi_c
(skylake) [VSC-4]$ mpirun -np 2 ./hello-mpi_c
Hello world from processor l44, rank 1 out of 2 processors
Hello world from processor l44, rank 0 out of 2 processors

Compiling code

Examples: compiling MPI code

  • Compiler: GNU
  • MPI: Intel
  • Language: C
  • ~training/examples/15_compiling/hello_mpi.c
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(skylake) [VSC-4]$ module purge
(skylake) [VSC-4]$ module load gcc/12.2.0-gcc-8.5.0-aal4zp2 intel-oneapi-mpi/2021.6.0-intel-2021.5.0-wpt4y32

Compile with optimization:

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(skylake) [VSC-4]$ mpicc -O2 -march=skylake hello-mpi.c -o hello-mpi_c
(skylake) [VSC-4]$ mpirun -np 2 ./hello-mpi_c
Hello world from processor l44, rank 1 out of 2 processors
Hello world from processor l44, rank 0 out of 2 processors

Compiling code

Examples: compiling MPI code

  • Compiler: AOCC
  • MPI: Openmpi
  • Language: C
  • ~training/examples/15_compiling/hello_mpi.c
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(zen3) [VSC-5]$ module purge
(zen3) [VSC-5]$ module load aocc/3.2.0-gcc-11.2.0-y53mdzyr openmpi/4.1.4-aocc-3.2.0-7abidzt

Compile without optimization:

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(zen3) [VSC-5]$ mpicc -O0 hello-mpi.c -o hello-mpi_c
(zen3) [VSC-5]$ mpirun -np 2 ./hello-mpi_c
Hello world from processor l54.vsc.xcat, rank 1 out of 2 processors
Hello world from processor l54.vsc.xcat, rank 0 out of 2 processors

Compiling code

Examples: compiling MPI code

  • Compiler: AOCC
  • MPI: Openmpi
  • Language: C
  • ~training/examples/15_compiling/hello_mpi.c
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(zen3) [VSC-5]$ module purge
(zen3) [VSC-5]$ module load aocc/3.2.0-gcc-11.2.0-y53mdzyr openmpi/4.1.4-aocc-3.2.0-7abidzt

Compile with optimization:

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(zen3) [VSC-5]$ mpicc -O2 -march=znver3 hello-mpi.c -o hello-mpi_c
(zen3) [VSC-5]$ mpirun -np 2 ./hello-mpi_c
Hello world from processor l54.vsc.xcat, rank 1 out of 2 processors
Hello world from processor l54.vsc.xcat, rank 0 out of 2 processors