An algorithm for threading assignment in large-scale wireless network mobile simulations

When using parallel computing to run large-scale simulations, the parts of the system being simulated in different cores or threads often interact and exchange information, constraining the threads to be synchronized. Simulating wireless networks with mobility, when a user equipment (UE) ceases to be served by one Base Station (BS), to be served by a new one, a synchronization point may be required, if the new BS is being simulated in another thread. In a large-scale distributed wireless network with high mobility, the simulation speed-up obtained from multi-threading could be lost to the overhead burden for synchronizing the threads. We propose a heuristic approach to assign BSs to threads in such a way as to minimize the number of synchronization points. In a time interval of the simulation, accumulated interactions are interpreted as growing graphs. Advancing through the simulation time until the number of disconnected graphs is equal to the number of desired threads, showed to be a good strategy to determine the longest intervals that can be simulated without synchronization points while taking advantage of multi-threading. By means of simulation tests we show decrements of up to 100.0 %, in the number of synchronization points, in comparison to those required for the same simulation times when assigning BSs to threads in a random and balanced way.