Load balancing in distributed computing over wireless LAN: Effects of network delay

A complete analytical solution to one-shot load balancing in a two-node distributed system is presented and verified experimentally. The model takes into account uncertainty in network delays and the variability in the processors' speeds. The system consisting of two Transmeta processors connected through a wireless LAN, utilizing an 802.11b access point, is used as the testbed. The statistics of the network delays are estimated experimentally and used in the analytical model to show the effect of the balancing instant and gain on the overall completion times of various workloads. The analytical results are verified by comparing them to actual experiments and Monte-Carlo simulation. The effect of the communication delay on the choice of the gain and the balancing instant is clearly observed. Finally, the model is used to determine the optimal gain and balancing instant for different initial load distributions.