Dynamic Hybrid Traffic Flow Modeling

SimulationEngine MultiCoreCPUSimulationEngine GPGPUSimulationEngine Figure 5: Simulation engines in SIMILAR 2.6 Probes The observation of the data of the simulation is managed using probes. Probes are objects listening to the evolution of the state of the simulation. Since the state of the simulation is not always consistent (especially during the computation of the reaction), the probes do not decide by themselves when to observe the simulation. Instead, they are registered to the simulation engine. The simulation engine is responsible to tell probes when the state of the simulation is consistent, and thus when probes can observe, process and export information about the simulation. The moments when the state of the simulation is consistent are: • After the initialization phase of the simulation, but before the execution of the operations related to the first time stamp of the simulation. • After the execution of a time stamp of the simulation (i.e. after the computation of the reaction leading to the update of the current time stamp of the simulation) • After the execution of the final time stamp of the simulation. Since simulations do not always execute peacefully, probes also have to manage the case when the simulation fails because of an error. Moreover, since some probes might use external resources, they also have to be notified when a new simulation will start. Consequently, probes are also notified when: