Abstract: A processing unit generates, in the initial setting of all-to-all communication between processes, a unique node-order process number for each process on the basis of hardware information, computes the virtual rank number of each process on the basis of the node-order process number of the process, and stores the computed virtual rank numbers in a storage unit. When performing the al-to-all communication between the processes, the processing unit determines the communication partner process of each process for the current step in the all-to-all communication by performing an exclusive OR operation between the virtual rank number of the process, stored in, the storage unit, and the step number of the current step. Then, the processing unit performs communication from each process to the corresponding communication partner process.

Abstract: A processing unit generates, in the initial setting of all-to-all communication between processes, a unique node-order process number for each process on the basis of hardware information, computes the virtual rank number of each process on the basis of the node-order process number of the process, and stores the computed virtual rank numbers in a storage unit. When performing the al-to-all communication between the processes, the processing unit determines the communication partner process of each process for the current step in the all-to-all communication by performing an exclusive OR operation between the virtual rank number of the process, stored in, the storage unit, and the step number of the current step. Then, the processing unit performs communication from each process to the corresponding communication partner process.