Software Routing and Aggregation of Messages to Optimize the Performance of HPCC Randomaccess Benchmark

The HPC challenge (HPCC) benchmark suite is increasingly being used to evaluate the performance of supercomputers. It augments the traditional LINPACK benchmark by adding six more benchmarks, each designed to measure a specific aspect of the system performance. In this paper, we analyze the HPCC randomaccess benchmark which is designed to measure the performance of random memory updates. We show that, on many systems, the bisection bandwidth of the network may be the performance bottleneck of this benchmark. We suggest an aggregation and software routing based technique that may be used to optimize this benchmark. We report the performance results obtained using this technique on the Blue Gene/L supercomputer