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docs.it4i/cs/arm.md

+# Using ARM partition
+
+For testing your application on the ARM partition,
+you need to prepare a job script for that partition or use the interactive job:
+
+```
+salloc -A PROJECT-ID -p p01-arm
+```
+
+On the partition, you should reload the list of modules:
+
+```
+ml architecture/aarch64
+```
+
+For compilation, `gcc` and `OpenMPI` compilers are available.
+Hence, the compilation process should be the same as on the `x64` architecture.
+
+Let's have the following `hello world` example:
+
+```
+#include "mpi.h"
+#include "omp.h"
+
+int main(int argc, char **argv)
+{
+        int rank;
+        MPI_Init(&argc, &argv);
+        MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+        #pragma omp parallel
+        {
+                printf("Hello on rank %d, thread %d\n", rank, omp_get_thread_num());
+        }
+        MPI_Finalize();
+}
+```
+
+You can compile and run the example:
+
+```
+ml OpenMPI/4.1.4-GCC-11.3.0
+mpic++ -fopenmp hello.cpp -o hello
+mpirun -n 4 ./hello
+```
+
+Please see [gcc options](https://gcc.gnu.org/onlinedocs/gcc/AArch64-Options.html) for more advanced compilation settings.
+No complications are expected as long as the application does not use any intrinsic for `x64` architecture.
+If you want to use intrinsic,
+[SVE](https://developer.arm.com/documentation/102699/0100/Optimizing-with-intrinsics) instruction set is available.