This operation performs a tree-wise data reduction operation (here:
bit-wise or) on all participating processes with MPI_Reduce and
then distributes the result to all participating nodes with MPI_Bcast. This result distribution to all paricipating nodes is
the difference to the normal MPI_Reduce operation, where the
result is stored in a single root processor. So it is interesting to
compare this operation to MPI_Allreduce, which distributes the
result to all nodes in one call. We vary over the number of nodes with a message
length of 256 Bytes for each node.
Pattern: Collective varied over number of nodes.
default values: 8 nodes, message length 256 units, max. / act. time for suite disabled/0.00 min.
