Performance Comparison of Real-Time and General-Purpose Operating Systems in Parallel Physical Simulation with High Computational Cost
Real-time simulation is a valuable tool in the design and test of vehicles and vehicle parts, mainly when interfacing with hardware modules working at a given rate, as in hardware-in-the-loop testing. Real-time operating-systems (RTOS) are designed for minimizing the latency of critical operations such as interrupt dispatch, task switch or inter-process communication (IPC). General-purpose operating-systems (GPOS), instead, are designed for maximizing throughput in heavy-load systems. In complex simulations where the amount of work to do in one step is high, achieving real-time depends not only in the latency of the event starting the step, but also on the capacity of the system for computing one step in the available time. While it is demonstrated that RTOS present lower latencies than GPOS, the choice is not clear when maximizing throughput is also critical.