LQN Based Performance Model for MCU Performance Prediction
Bian Xue · Chinese Journal of Computers · 2004
Performance models are powerful tools to evaluate potential system configuration. The layered queue network (LQN) model is widespread used to predict performance of parallel and distributed system. In this paper LQN model is extended by import pseu task and operation task to build performance model of H.323 multipoint control unit (MCU) which will be performance bottle neck in large scale videoconference system. The model build by analyzing media data flow throughout MCU software and hardware include OS and network diver. The model parameters are obtained by several methods such as using network measure tool, adding check point in software, analyzing network data flow. Then the performance parameters can be easily achieved using simulation method. Different software and hardware architecture are evaluated using the LQN model with only different model parameters. By this method it is found the terminal connection capability of MCU can be improved 50% using dual CPUs and multithread architecture in LQN model simulation. The method is proved valid by comparing results with a real system.