实时CORBA中面向紧急通道的任务调度

Task scheduling in real-time CORBA for emergency passage

为了保障紧急通道任务在实时CORBA(通用对象请求代理体系结构)中优先执行,并且避免因状态切换而导致的任务通道优先级倒置.本文提出了面向紧急通道的实时任务调度方案和设计思路,方案考虑到任务通道的状态切换,采用了自适应动态优先级调度的方法,在连接管理和服务线程调度等方面做了相关的处理.分析表明,紧急通道任务能获得最高的优先级,出现因状态不一致而导致的低优先级通道任务阻塞高优先级通道任务的概率很小;且在一个节点上,调度算法保证紧急通道任务优先完成,不会出现紧急通道任务在节点上等待的现象,满足了应用的需求.

In order to ensure the tasks of emergency passage are scheduled first and avoid priority inversion by the switches of system states in CORBA（common object request broker architecture） system, a real-time scheduling scheme is proposed and analyzed which adopts an adaptive dynamic priority scheduling algorithm. The scheme considers the switches of system states. It also takes account of connection management and thread pool management. Analysis shows that the tasks of emergency passage can take priority over others, and the probability is negligible that inconsistent system states result in low-priority tasks blocking high-priority ones. Besides, tasks of emergency passage will never wait under this algorithm, so their execution is ensured on each node, which meets the needs of application.