Performance evaluation is very important for reconfigurable processor, for we can estimate the approximate performance before we actually run a program on the system hardware. In this paper, we try to find a new method to evaluate the system performance by simply analyzing the configuration contexts. With a C++ evaluation model constructed, we can extract the effective information from the configuration files and get the system performance rapidly, based on careful timing analysis. Experiments show that the evaluation model's results and the simulation results match fairly well, and time cost will also be saved significantly, especially when the computing task grows more complex.