LogfP - a model for small messages in InfiniBand

Accurate models of parallel computation are often crucial to optimize parallel algorithms for their running time. In general the easier the model´s use and the smaller the number of parameters and interdependencies among them, the more inaccuracies are introduced by simplification. On the other hand a too complex model is unusable. We show that it is possible to derive a relatively accurate and easy model for small message performance over the InfiniBand network. This model allows the developer to gain knowledge about the inherent parallelism of a specific InfiniBand hardware and encourages him to use this parallelism efficiently. Several well known models hide this feature and some of them even penalize the use of parallelism because the model designers were not aware of new emerging architectures like InfiniBand