Parallel logic simulation using Time Warp on shared-memory multiprocessors

Abstract

The article presents an efficient parallel logic-circuit simulation scheme based on the Time Warp optimistic algorithm. The Time Warp algorithm is integrated with a new global virtual time (GVT) computation scheme for fossil collection. The new GVT computation is based on a token ring passing method, so that global synchronization is not required in a shared-memory multiprocessor system. This allows us to process large logic simulation problems, where the GVT computation is executed frequently for fossil collection due to limited memory space. We also present how to reduce the frequency of the GVT computation and the rollback radio by scheduling the process with the smallest timestamp first. We implement the parallel logic-circuit simulator using the Time Warp on BBN Butterfly machines, and the experimental results show that the algorithm provides a significant speedup in processing time, even for very large circuits. >