Real-time fault-tolerant scheduling algorithm for distributed computing systems

This article proposes a Distributed Realtime Fault-tolerant model, priority Real-time Fault-tolerant algorithm and computational architecture of Distributed Real-time Fault-tolerant. According to this model, the problem of how to schedule a weighted Directed Acyclic Graph (DAG) in Distributed computing system for high reliability can be solved in the presence of multiprocessors faults. When some tasks in a DAG have dependence on each other, a task must be scheduled to make sure that maximum communication efficiency and high reliability can be guaranteed due to a processor failure. Firstly, this paper propose task model, communication model and reliability model for evaluating fault-tolerant performance of the system, and define the priority of a task so that a critical task is defined as one with the highest priority. To add some constrained conditions that do not influence the earliest start time of its successors in the process of scheduling task, The Distributed Realtime Fault-tolerant Scheduling Algorithm (DRFACS) targets maximizing reliability to dynamically schedule dependent, non-preemptive, non-periodic real-time tasks to improve the quality of service through scheduling in the case of arising massive resource failures. Finally, Experimental results demonstrate the feasibility of the proposed algorithm.