Corolla partitioning for distributed logic simulation of VLSI-circuits

Abstract

Time Warp has evolved to a common technique for distributed simulation. Speedup in Time Warp simulation systems mainly depends on two overhead factors: first, the load on the simulators has to be well balanced and second, communication and rollbacks have to be kept to a minimum. Both of these factors are influenced by the partitioning of the simulated system. In this paper, we focus on various static partitioning schemes used to partition digital circuits for distributed simulation. A new hierarchical partitioning approach is presented, compared and rated with other partitioning schemes by evaluating benchmark circuits. Partitioning is done in two steps: a fine grained clustering step based on corollas and a coarse grained step forming partitions using the connectivity matrix. The corolla approach yields very good partitioning results even for a large number of partitions. The achieved speedups are almost linear (up to 12 partitions for larger circuits), as long as the partition sizes are large enough so that communication between the simulators is not a bottleneck. The results reveal the great impact of partitioning on the acceleration of distributed logic simulation and show the effectiveness of the presented corolla partitioning scheme.