Improving the performance of optimistic time management mechanism with sub-state saving

Görür B. K., Imre K., Oǧuztüzün H., Yilmaz L.

25th High Performance Computing Symposium, HPC 2017, Part of the 2017 Spring Simulation Multi-Conference, SpringSim 2017, Virginia, United States Of America, 23 - 26 April 2017, vol.49, pp.117-128 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 49
  • City: Virginia
  • Country: United States Of America
  • Page Numbers: pp.117-128
  • Middle East Technical University Affiliated: Yes


©2017 Society for Modeling & Simulation International (SCS).Optimistic approaches are scalable methods for time management in parallel and distributed simulations. In optimistic time management, logical processes advance their local time without constrained by the others in the simulation. If a logical process receives a message from its past, it goes back to a previously saved state, which is called a rollback. Even though the received message from the past would not cause any problem, rollback is performed in any case. In this paper, we presented a method to reduce the number of rollbacks, without sacrificing the accuracy of simulation. We propose to save a relatively small subset of the full simulation state to allow the logical processes to make a decision whether a rollback is really needed or not. Our technique is demonstrated in an agent-based simulation using the Time Warp algorithm adapted for optimistic time management for Repast HPC.