Measuring Communication and Computation Overlap
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Measuring Pure Communication Time
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iallgather
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iallgather_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iallgatherv
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iallgatherv_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iallreduce
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iallreduce_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ialltoall
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ialltoall_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ialltoallv
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ialltoallv_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ibarrier
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ibarrier_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ibcast
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ibcast_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Igather
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Igather_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Igatherv
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Igatherv_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ireduce
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ireduce_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ireduce_scatter
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Ireduce_scatter_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iscatter
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iscatter_pure
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iscatterv
                                                    
                                                    
                                                
                                                    
                                                    
                                                        Iscatterv_pure
                                                    
                                                    
                                                
                                            
                                        S_[ACTION]_expl
This benchmark mimics the same situation as S_[ACTION]_indv, with a different strategy to access files. See the basic definitions and a schematic view of the pattern below.
S_[ACTION]_expl Definition
| Property | Description | 
|---|---|
| Measured pattern | As symbolized in the figure I/O benchmarks, aggregation for output | 
| Elementary I/Oaction | As symbolized in the figure below. | 
| MPI routines for theblocking mode | MPI_File_write_a t/MPI_File_read_at | 
| MPI routines for thenonblocking mode | MPI_File_iwrite_at /MPI_File_iread_at | 
| etype | MPI_BYTE | 
| File type | MPI_BYTE | 
| MPI data type | MPI_BYTE | 
| Reported timings | t (in μsec) as indicated in the figure I/O benchmarks, aggregation for output, aggregate and non-aggregate for the Write flavor. | 
| Reported throughput | x/t, aggregate and non-aggregate for the Write flavor | 
S_[ACTION]_expl pattern
