An analytical model of inter-node communication towards performance prediction of multi-node systems

Our goal is to predict the performance of multi-node systems consisting of identical processing nodes based on single node profiles. We clarified how much inter-node communication is caused on n-node systems because the performance significantly depends on the communication amount. However, the amount when business applications such as databases are running is difficult to predict for the following reasons: first, applications are closed and/or complex. Second, workloads vary from system to system. Third, the number of nodes affects the amount. We analytically model the amount under a simple cache coherence mechanism. Our model predicted, with a high degree of accuracy, the number of transfers of cached copies obtained by simulation. Even though our model explains the transfers only under a simple mechanism, the model should explain a fundamental part of those under more complex ones.