分级调度实时架构中处理器资源预设值的预借性

Resource Borrowing Mechanism Based on Hierarchical Scheduling Real-Time Framework

分层多级自适应调度(AdHierSched)架构是Linux操作系统中的虚拟实时架构,在系统运行时,它通过监测各子系统对处理器资源的需求动态调整资源分配。本文在分级调度架构中提出了处理器资源预借机制(BBM),通过服务器间资源的动态分配达到处理器资源在各个实时系统中优化配置的目的,并针对AdHierSched架构中资源预设值的预借性进行设计和实现,通过静态任务和动态任务对该资源预设值预借控制器进行实验评估。实验结果表明:当AdHierSched架构伴随着处理器预借机制和资源调整机制同时运行时,内部运行任务整体的截止期限超出率减小。此外,资源预借性机制的添加导致的系统额外开销相比系统总的开销很小,表明该方案适合在实际分级调度实时系统内推广使用。

Multi-level adaptive hierarchical scheduling(AdHierSched)framework is a virtualized realtime framework in Linux operating system,which dynamically schedules the CPU partition sizes by monitoring the demand of every subsystem during running process.This paper presents a Budget Borrowing Mechanism(BBM)in hierarchical scheduling framework.The proposed BBM can dynamically assign the CPU resource between servers in real-time systems.Moreover,in AdHierSched framework,the proposed BBM is designed and implemented for dynamical adaptation the resource parameters.Both static and dynamic tasks are utilized to evaluate the budget borrowing controller.Experiment results show that while different tasks execute in the framework with the proposed BBM,the task's deadline miss ratio is lower than those without using this mechanism.Compared with the total overhead of system,the extra overhead from budget borrowing calculation is very small.Hence,the proposed mechanism is suitable in actual applications.