Message exchange during parallel execution of processes in a high-performance computer

Processes pending execution in respective compute nodes (N1-Nn) of a cluster of a distributed HPC computer can communicate with one another by message exchange through an interconnected fabric. To exchange messages between the processes a method is proposed to identify the physical cards associated with the compute nodes directly from the hostname of the compute nodes as they are used in the user program. This direct identification is made from at least one mapping table (MT1) associating bijectively the hostname of each compute node of the cluster with the unique logical address of the associated physical card. This mapping table is kept in a component of the computer responsible for managing the fabric, i.e. the fabric manager (FM1). Various implementations enable scaling when accomplishing the method of message exchange between processes.