Schedulability of rollback recovery fault-tolerant real-time system based on priority mixed strategy
Wanfu Ding · Journal of Jilin University · 2012
A real-time system must guarantee the stringent requirements of real-time response and reliability.Taking account of the effects of errors,an investigation of the schedulability of fault-tolerant real-time systems was conducted based on the rollback recovery fault-tolerant model.A priority mixed strategy of fault-tolerance was proposed,and the computing formula of worst-case response time of a task under the new strategy is deduced.The new strategy allows the faulty task to execute at higher or lower priority levels.According to the schedulability analysis,an efficient priority assignment search algorithm(FTPCS_MS) was proposed.The algorithm reduces the search space of optimal fault-tolerant priority mixed assignment from O(nn) to O(n2).The simulation shows that the mixed strategy can improve system fault resilience efficiently.