Test 2 -- MPI Flooding
This is a host-level test that involves flooding messages to a root rank.
Each rank gets to be the root for one sequence of flooding operations.
During the flooding the root sends a small ping to its neighbor to active X
ranks to send it a message back. The total bandwidth of this is measured,
and X is increased until the total bandwidth drops to 25% of the best
bandwidth seen. The graphs then report two things
- best bandwidth seen while flooding to each host
- max number of hosts engaged in flooding before a large drop was seen
So the first set of graphs below will be showing bandwidths, and
the second set will be showing host counts for the same runs.