The present invention is achieved as software which operates on a computer system and which performs calculation by receiving various data as inputs, and which outputs values. The present invention is applicable to a coarse-grained system architecture model including the foregoing event-driven simulation and receives, as inputs, execution time T and the number of memory accesses, N, in the simulation step of the model. Thus, various estimates at the occurrence of memory access conflict are obtained at a simulation speed sufficient for evaluating the effect of the memory access conflict and comparing it with many alternative architectures without information on the correct timing of memory accesses in consideration of memory synchronous accesses and arbitration. The results of this simulation are estimated simulation-step execution time T′ under memory access conflict and memory-bandwidth utilization factors {U′i} in individual simulation steps under memory access conflict.