This paper presents a novel technique for the modeling, simulation, and analysis of real-time applications on MultiProcessor Systems-on-Chip (MPSoCs). This technique is based on an application-transparent emulation of OS primitives, including support for RTOS elements. The proposed methodology enables a quick evaluation of the real-time performance of an application in front of different design choices, including the study of system’s behavior as tasks’ deadlines become stricter or looser. The approach has been verified on a large set of multi-threaded benchmarks. Results show that our methodology (a) enables accurate realtime and responsiveness analysis of parallel applications running on MPSOCs, (b) allows the designer to devise an optimal interrupt distribution mechanism for the given application, and (c) helps dimensioning the system to meet performance and real-time needs.