Dear All,

In one of our application I am seeing following error while using collective call MPI_File_write_all :

Error in ADIOI_Calc_aggregator(): rank_index(1) >= fd->hints->cb_nodes (1) fd_size=102486061 off=102486469

Non collective version works fine.

While looking at callstack I came across below comment in mpich-3.2/src/mpi/romio/adio/common/ad_aggregate.c :

/* we index into fd_end with rank_index, and fd_end was allocated to be no

* bigger than fd->hins->cb_nodes. If we ever violate that, we're

* overrunning arrays. Obviously, we should never ever hit this abort */

if (rank_index >= fd->hints->cb_nodes || rank_index < 0) {

FPRINTF(stderr, "Error in ADIOI_Calc_aggregator(): rank_index(%d) >= fd->hints->cb_nodes (%d) fd_size=%lld off=%lld\n",

rank_index,fd->hints->cb_nodes,fd_size,off);

MPI_Abort(MPI_COMM_WORLD, 1);

}

I am going to look into application and see if there is an issue with offset overflow. But looking at above comment ("Obviously, we should never ever hit this abort ") I thought should ask if there is any obvious thing I am missing.

Regards,

Pramod

p.s. I will provide reproducer after looking into this more carefully.