In my fortran code, I used mpi_bcast to broadcast an array Q(21, 51,
140000) (the size for it is 150,000,000) from the root to all the nodes. I
found when I used this bcast subroutine, it code will be very slow and
sometimes it hangs there. Once I commented this array, this code speed is
normal. So I guess that the Q is too large to be broadcast using mpi_bcast.
Is my judgement correct?
I think this array is required for my code, but now the troublesome thing
is that the speed is slow. Does anybody know how to alleviate this problem
? Or any other alternative problems to make this array Q broadcast from
root to other nodes?
Thank you in advance.