Continue the analysis of your application with information provided by other charts.
In the Function Profile chart, open the Load Balance tab.
Go to the Charts menu to open a Message Profile.
In the Load Balance tab, expand MPI_Sendrecv and MPI_Allreduce. The Load Balancing indicates that the time spent in MPI_Sendrecv increases with the process number, while the time for MPI_Allreduce decreases.
Examine the Message Profile Chart down to the lower right corner. The color coding of the blocks indicates that messages travelling from a higher rank to a lower rank need proportionally more time while the messages travelling from a lower rank to a higher rank reveal a weak even-odd kind of pattern.