Message Scheduling for All-to-all Personalized Communication on Ethernet Switched Clusters

We develop a message scheduling scheme that can theoretically achieve maximum throughput for all--to--all personalized communication (AAPC) on any given Ethernet switched cluster. Based on the scheduling scheme, we implement an automatic routine generator that takes the topology information as input and produces a customized MPI alltoall routine, a routine in the Message Passing Interface (MPI) standard that realizes AAPC. Experimental results show that the automatically generated routine consistently out-performs other MPI alltoall algorithms, including those in LAM/MPI and MPICH, on Ethernet switched clusters with di#erent network topologies when the message size is su#ciently large. This demonstrates the superiority of the proposed AAPC algorithm in exploiting network bandwidths