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
                                                    
                                                    
                                                
                                            
                                        IMB-EXT Benchmarks
This section provides definitions of IMB-EXT benchmarks. The benchmarks can run with varying transfer sizes X, in bytes. The timings are averaged over multiple samples. See the Benchmark Methodology section for details. In the definitions below, a single sample with a fixed transfer size X is used.
The Unidir and Bidir benchmarks are exact equivalents of the message passing PingPong and PingPing, respectively. Their interpretation and output are analogous to their message passing equivalents.