Influence of Communication Models on the Scalability of Master-Slave Platforms Running Bag-of-Tasks Applications

Bag-of-Tasks applications are parallel applications composed of independent (i.e., embarrassingly parallel) tasks that do not communicate with each other, may depend upon one or more input files, and can be executed in any order. Each file may be input for more than one task. A common framework to execute BoT applications is the master-slave topology. In this paper we studied the scalability of BoT applications running on multi-node systems (e.g. clusters and grids) organized as master-slave platforms, considering two communications paradigms: multiplexed connections and efficient broadcast. We prove that the lower bound on the isoefficiency function for master-slave platforms is achievable by those platforms that have an efficient broadcast primitive available. Our study employs a set of simulation experiments that confirms the theoretical results.