Schedulability of Fault Tolerant Real Time System Based on Local Optimum Checkpoint Under Priority Mixed Strategy

Abstract

Against the defect of the real time system fault tolerant model that can only tolerate one fault, the Local optimum checkpoint (LOC) algorithm was proposed. Then according to the schedulability analysis, the worst case response time formula under the fault tolerant priority mixed strategy based on the local optimum checkpoint was deduced. Finally the Fault tolerant priority configuration search algorithm under Mixed strategy based on LOC (FTPCS-MS-LOC) was proposed. The FTPCS-MS-LOC can toleratemultiple transient faults. The algorithm can effectively reduce the search space compared to the enumeration method. The simulation shows that the FTPCS-MSLOC can significantly improve the system fault resilience than the fault tolerant priority inheritance, promotion and demotion strategy, and also the mixed strategy based on the checkpoint interval in the condition of single fault occurred.