The fault dropping problem in concurrent event-driven simulation

The dynamic removal of faults before the end of the test pattern is reached, called fault dropping (FD), is considered. The conventional technique, called synchronous FD, is analyzed. An asynchronous FD method is introduced and its performance compared with that of the conventional method. It is based on the concept of removing descriptors while the simulation procedures access the data structure. This technique guarantees the maximum efficiency in reducing the computational effort. Experimental results show that it can considerably speed up simulation, particularly for large networks. It is shown that a mixed synchronous/asynchronous approach can optimize the total amount of memory needed