| Popis: |
The problem of guaranteeing "meet row n in m" weakly hard real-time constraint is addressed in this paper. The paper first analyzes characters of /spl mu/-pattern and gives out the definition of "unsatisfied /spl mu/-pattern". Then, it enumerates and proves several properties of unsatisfied /spl mu/-pattern. According to the properties, length of unsatisfied /spl mu/-pattern can indicate whether the /spl mu/-pattern satisfies the meet row constraint, therefore, a scheduling algorithm named meet row algorithm is presented based on the properties. Meet row algorithm tries to find out the probabilities of tasks breaking constraints and increase task's priority in advance. Simulation results show that meet row algorithm is better than other scheduling algorithms for meet row constraints and can largely decrease the worst-case computation time of real-time tasks. |
