On Wed, 2007-08-29 at 11:36 -0400, Terry D. Dontje wrote: > To run the code I usually do "mpirun -np 6 a.out 10" on a 2 core > system. It'll print out the following and then hang: > Target duration (seconds): 10.000000 > # of messages sent in that time: 589207 > Microseconds per message: 16.972 >
I know almost nothing about FORTRAN but the stack dump told me it got NULL pointer reference when accessing the "me" variable in the do .. while loop. How can this happen? [ollie@exponential ~]$ mpirun -np 2 a.out 100 [exponential:22145] *** Process received signal *** [exponential:22145] Signal: Segmentation fault (11) [exponential:22145] Signal code: Address not mapped (1) [exponential:22145] Failing at address: (nil) [exponential:22145] [ 0] [0xb7f2a440] [exponential:22145] [ 1] a.out(MAIN__+0x54a) [0x804909e] [exponential:22145] [ 2] a.out(main+0x27) [0x8049127] [exponential:22145] [ 3] /lib/libc.so.6(__libc_start_main+0xe0) [0x4e75ef70] [exponential:22145] [ 4] a.out [0x8048aa1] [exponential:22145] *** End of error message *** call MPI_Send(keep_going,1,MPI_LOGICAL,me+1,1, $ MPI_COMM_WORLD,ier) 804909e: 8b 45 d4 mov 0xffffffd4(%ebp),%eax 80490a1: 83 c0 01 add $0x1,%eax It is compiled with g77/g90. Ollie