【摘要】 实时系统应当具有可预期的定时行为,强实时约束要求系统必须满足定时约束和时限要求.以周期性任务模型作为网络负载可以准确地描述强实时约束下的系统性能.本文以光纤通道交换网络强实时约束下的性能研究为背景,根据调度实时消息传输的加权轮转服务规程,提出了特定消息集的优化设计算法,推导并证明了采用该优化算法后系统最坏情况下的可达负载率比不采用该算法时可提高至少一倍.更多还原

【Abstract】 A real-time system is required to complete its work and deliver its sevices on a timely basis.We lays much emphasis on hard real-time characteristics of the system,because hard real-time performance is one important performance requirement of special system such as avionics network.The periodic task model is a well-known deterministic workload.With its various extensions,the model characterizes accurately many traditional hard real-time applications.Switched fabric is one of basic fibre channel topology.Fixed-length packet scheme is mainly used in fibre channel switches.Taking the study on fibre Channel switch fabric under hard real-time constraints as background,an optimization design of typical message set is proposed according to the weighted round-robin algorithm.It is derived and formally proved that the achievable utilization using the optimization design can be doubled at least.更多还原