Dear Madam/Sir,
I have a serial Fortran code (f90), dealing with matrix diagonalizing subroutines, and recently got its parallel version to be faster in some unfeasible parts via the serial program. I have been using the following commands for initializing MPI in the code --------------- call MPI_INIT(ierr) call MPI_COMM_SIZE(MPI_COMM_WORLD, p, ierr) call MPI_COMM_RANK(MPI_COMM_WORLD, my_rank, ierr) CPU requirement >> pmem=1500mb,nodes=5:ppn=8 << ------------------- Everything looks OK when matrix dimensions are less than 1000x1000. When I increase the matrix dimensions to some larger values the parallel code gets the following error ------------------ mpirun noticed that process rank 6 with PID 1566 on node node1082 exited on signal 11 (Segmentation fault) ------------------ There is no such error with the serial version even for larger matrix dimensions than 2400x2400. I then thought it might be raised by the number of nodes and memory space I'm requiring. Then changed it as follows pmem=10gb,nodes=20:ppn=2 which is more or less similar to what I'm using for serial jobs ( mem=10gb,nodes=1:ppn=1). But the problem persists still. Is there any limitation on MPI subroutines for transferring data size or the issue would be raised by some cause else? Best of Regards, Mohammad