Small clusters - MPI usage for solving MHD equations with the FLASH code

Despite fast development of computer technology some numerical problems are still too complex to be solved using personal computers. In such cases the use of supercomputers can be a good choice. However, running jobs at computer centers involves necessity of queuing. Additionally, problems with fast transmission may arise if output files are large enough. An alternative solution is to build multiprocessor clusters of computers on which Message Passing Interface is implemented. In this paper application of MPI is presented for the case of the FLASH code which solves initial-value problems for magnetohydrodynamic equations.