分布式实时系统请求接收单元优先级的研究

Research on Receiving Priority in Distributed Real-Time System

基于固定优先级调度的分布式实时系统中,服务方对请求的处理分为两个阶段,请求接收阶段和请求执行阶段。其中请求的接收一般是由接收单元统一负责,而接收单元并不知道请求的优先级,只有在解码后才能知道请求的优先级并按照优先级进行相应的处理。那么接收单元本身的优先级如何确定呢?该文针对这一问题进行了深入的研究。在对系统进行建模并取得模拟结果后得出了重要结论,在基于固定优先级调度的分布式实时系统中,服务方接收单元的优先级要小于最高优先级,大于其他优先级。

In the distributed real-time systems based on fixed priority schedule,the server firstly receives the request message,then executes the message.In the first stage,we do not know the priority of the request till unmarshal the message.So the priority of the receiving unit is very important to the whole system and is hard to set.We built the model of the server and simulated the source.After analyzing the result,we drew a very important conclusion,the priority of the receiving unit must be lower than the max priority of requests and higher than other priorities.