Estudo sobre impacto da criação dinâmica de processos do MPI-2 no desempenho de duas aplicações paralelas

Abstract

MPI (Message-Passing Interface) is the standard for messaging-passing paradigm in distributed parallel computing systems. The MPI-2 standard, besides the ability to create processes statically at the beginning of execution, as in the MPI-1 standard, adds the possibility of dynamically creating processes at run time. This work aims to compare implementations with static and dynamic creation of processes about the performance and use of computational resources to investigate the overhead caused by the dynamics creation of processes in two applications with regular and irregular workload. Para isso foram utilizadas implementações MPI-1 e MPI-2 dos problemas do Jogo da Vida e Skyline Matrix Solver. In the first analysis through the Game of Life it was possible to verify the impact of the dynamic creation of processes in applications with regular workload and whose computation time is similar between the processes. Our results show that the overhead in applications MPI-2 was attenuated by the communication model adopted. Memory consumption, context switches, interrupts have very similar behavior except the initial stages of the runs for both versions. CPU usage was 100% for all cases during execution, except for executions with 32 processes that oscillated during execution. The second analysis of the Skyline Matrix Solver was able to verify the impact of the creation of processes at run time in applications with irregular workload. Our results show that for this application the insertion of dynamic process creation had a negative impact on the performance of the application when compared to static creation. The memory consumption was lower for all executions in the version with dynamic process creation except for execution with 16 processes where this situation is reversed. However, the version with creation of processes at run time had a greater number of context changes and interruptions due to irregular communication of the application.