Schedulability Modelling And Analysis On Multi-core Systems

With the widely application of real-time systems, studies on Real-time systemattract increasingly more attention. Compared with other systems, real-time systems'total correctness of an operation not only depends on its logical correctness, but al-so upon the time it which it is completed. Real-time systems can complete systemfunctions or react to external or internal and synchronous or asynchronous actions in aspecified time or a determined time. Classically, real-time systems are categorized ashard real-time systems and soft real-time systems. In hard real-time systems, its resultis considered useless if an operation completes after its deadline, and it may even causethe critical failure of the whole system. On the other hand, soft real-time systems cantolerate such lateness, and may respond with decreased service quality. In schedula-bility analysis, we are concerned with hard real-time systems. Schedulability plays animportant role in real-time system design. Whether tasks can be scheduled on it de-termines its application of the system. Early real-time systems have simple functions,like Single-chip microprocessor, Single-board computer and other simple embeddedreal-time systems. Their scheduling strategy is also simple. With the increasing appli-cation of real-time systems, it is increasinly more complicated, and real-time systemstake on new characteristics, for example, the introduction of multi-core processors.In recent years model-checking methods have been successfully applied to schedu-lability analysis. Derivatives of timed automata have been expressive in time, which isan important dimension in real-time system. Among them, Task automata introducestask triggered by time, the minimum schedulable unit, into its model, such that it be-comes more expressive in the relationships between time and tasks. It's suitable formodelling real-time systems with non-uniformly recurring computation tasks. A taskautomaton is schedulable if there exists a scheduling strategy such that all possible sequences of events generated by the automaton are shcedulable in the sense that allassociated tasks can be computed within their deadlines.Scheduling strategies on real-time systems can be categorized as non-preemptiveone and preemptive one. This paper will discuss the schedulability analysis on multi-core systems based on task automaton, presenting modelling methods and analysis forboth strategies.