A Simple Synchronous Distributed-Memory Algorithm for the HPCC RandomAccess Benchmark

The RandomAccess benchmark as defined by the High Performance Computing Challenge (HPCC) tests the speed at which a machine can update the elements of a table spread across global system memory, as measured in billions (giga) of updates per second (GUPS). The parallel implementation provided by HPCC typically performs poorly on distributed-memory machines, due to updates requiring numerous small point-to-point messages between processors. We present an alternative algorithm which treats the collection of P processors as a hypercube, aggregating data so that larger messages are sent, and routing individual datums through dimensions of the hypercube to their destination processor. The algorithm’s computation (the GUP count) scales linearly with P while its communication overhead scales as log2(P), thus enabling better performance on large numbers of processors. The new algorithm achieves a GUPS rate of 19.98 on 8192 processors of San

• Type: Conference
• Year: 2006
• Where: CLUSTER
• Authors: Steven J. Plimpton, Ron Brightwell, Courtenay Vaughan, Keith D. Underwood, Mike Davis
• Keywords: CLUSTER 2006, Cluster Computing, Performance Computing Challenge, Processors, Small Point-to-point Messages