Adaptive checkpointing in Time Warp

Abstract

In Time Warp optimistic discrete event simulation, there exists a need to occasionally save the states of the logical processes. The state saving often constitutes a substantial overhead. However it is not necessary to save each state of a logical process since states can be restored from earlier states by re-executing intermediate events. In this paper, we analyse the effects of doing the state saving less frequently and present a method that allows each logical process to adapt its state saving interval to its rollback behaviour. Experimental results indicate that the proposed method improves performance of the Time Warp system.