Dynamic load redistribution based on migration latency analysis for distributed virtual simulations

Distributed virtual simulations deployed on shared resources can frequently undergo loss of performance due to external background load, improper placement of simulation entities, or dynamic simulation load changes. The High Level Architecture (HLA) was designed as a solution for coordinating the execution of distributed simulations. Even though this framework offers management services to organize such simulations, it does not provide mechanisms for detecting and controlling load imbalances. Several balancing approaches have been designed aiming at a generic scheme for solving load imbalance issues of distributed simulations, but these approaches are concerned with issues of specific simulation applications or are unaware of environment characteristics. To overcome such limitations, a dynamic, distributed balancing scheme has been developed. However, the scheme is not aware of federate migration latencies. Since migration latency directly influences balancing efficiency and responsiveness, a redistribution scheme is proposed to measure migration delays and use such delays in the balancing algorithm to determine load deployment changes. These delays are used in a cost function that determines the redistribution behaviour of the balancing scheme. Experiments have been performed to analyze the performance gain of the proposed scheme when migration procedures introduce costly latencies into simulations.