先进控制理论在软实时系统反馈调度中的应用研究
文献类型：学位论文
| 作者 | 魏立峰 |
| 学位类别 | 博士 |
| 答辩日期 | 2004-02-06 |
| 授予单位 | 中国科学院沈阳自动化研究所 |
| 授予地点 | 中国科学院沈阳自动化研究所 |
| 导师 | 于海斌 |
| 关键词 | 软实时系统 实时调度 先进控制 QoS 多媒体通信 |
| 其他题名 | Research on Feedback Control Scheduling in Soft Real-time System Based on Advanced Control Theory |
| 学位专业 | 机械电子工程 |
| 中文摘要 | 控制理论应用于软实时系统的调度问题，基本停留在经典控制技术应用水平。由于软实时系统模型的复杂性如非线性、参数时变、积分时变时滞等特性，采用经典反馈控制技术存在较大的局限性。本文主要以软实时系统中的典型对象客户-服务器作为研究背景，对实时CPU资源调度和实时多媒体流控的模型及反馈控制算法进行研究，将先进控制理论中的一些思想方法运用到反馈调度算法中，克服了经典反馈控制技术的局限性，提高了反馈控制理论在软实时系统中应用的实效性，为控制理论在复杂软件系统中的进一步应用拓展了空间。本文的主要工作和贡献有： 1.在CPU资源反馈调度中，深入研究了CPU利用率 的饱和区与任务丢失率 的饱和区互斥特性，提出了一种基于混合控制的反馈控制实时调度算法，有效地解决了实时系统的非线性问题，实现了全局线性化反馈。该调度算法提高了系统的利用率并降低系统的丢失率，获得了令人满意的系统性能。 2.针对CPU资源实时调度模型的时变参数特点，本文提出了一种基于自适应反馈控制结构的软实时调度算法，改善了实时系统的稳态和动态响应特性，同时对系统模型的参数时变具有较好的鲁棒性，提高了资源的利用率。 3.以CPU资源调度为典型应用背景展开研究，研究和分析了采样周期对反馈控制实时调度和一般数字控制系统性能影响的差异，对选用传统硬实时系统中周期性任务的宏周期作为采样周期的可行性进行了研究，并通过仿真实验得出采样周期的选择对反馈控制实时调度性能影响规律，提出了具有普遍意义的采样周期选择方法。 4.完善了实时多媒体反馈控制框架中负载行规和性能评价指标体系，为评价各种反馈控制算法的综合性能度量提供了依据。 5.将“流程”工业中物料平衡控制中的先进控制技术映射到实时多媒体流控的反馈控制算法设计中，在实时多媒体流控的反馈控制算法中采用模型预测方法与优化技术相结合，设计了基于缓冲区长度的模型预测最优均匀控制算法，并通过仿真实验验证了该方法的有效性。 6.考虑到网络传输过程中的各种延迟，缓冲区长度与速率模型可归结为积分时滞过程，采用先进的内模控制和模型预测最优均匀控制理论进行了控制结构和算法设计。仿真实验表明这些算法在克服积分时滞及积分时变时滞问题方面，是非常有效的解决方法。 7.提出了实时CPU资源调度与基于缓冲区长度的速率反馈控制协同设计思想，为全面提高CPU资源利用率、网络带宽利用率及QoS保证提供了理论和方法的指导。 |
| 索取号 | TP273/W55/2003 |
| 英文摘要 | It is heavily limited that only the conventional control approaches are mainly adopted to resolve soft real-time system scheduling problems, because of the complexity of the soft real-time system model such as non-linear, time-varied parameters and integral delay etc. This paper takes the client-server models as the applied background, and researches deeply on the scheduling problems about real-time CPU resources and real-time multi-media traffic control. The advanced control ideas are applied to the feedback control scheduling algorithms, which overcome the limitation of the conventional control technology, and enhance the effect of feedback control theory applied in the soft real-time system. The areas of the application of control theory to complex software systems are enlarged. The main work and contribution of this paper are as follows: 1.In the feedback scheduling of CPU resource, a novel hybrid feedback-control scheduling algorithm is presented in this paper, which solves non-linear of real-time system effectively. The general linear feedback control is realized. The high utilization and low miss-ratio are obtained. 2.A soft real-time scheduling algorithm based on the adaptive feedback control architecture is presented in the paper. The robust is demonstrated when the system parameter is varied. The steady and dynamic response performances are improved. The utilization of resource is increased. 3.The general method of sampling period choice is also presented in this paper. For task sets whose average execution time is difficult to predict, an effective method of variant sampling period is presented. 4.The load profile and performance specifications in the real-time multi-media feedback- control frame is perfected, which support the integrated evaluation of performance to different feedback control algorithms. 5.The model prediction and optimal technology are combined together to design the model predictive optimal averaging level control algorithm based on the buffer occupancy, which verifies the validity of the method through the simulation experiments. 6.The internal model control and model predictive optimal averaging level control are adopted to design the control structure and algorithm. The simulation experiment demonstrates that these algorithms are very effective solutions to overcoming the integral delay and integral time-varying delay. 7.The co-design idea of real-time CPU resource feedback control scheduling and traffic feedback control based on buffer occupancy is proposed. It is the author’s expectation that this idea will supply a methodology to improve overall CPU resource utilization, network width utilization and service of quality. |
| 语种 | 中文 |
| 公开日期 | 2012-08-29 |
| 产权排序 | 1 |
| 分类号 | TP273 |
| 源URL | [http://ir.sia.ac.cn/handle/173321/9478]  |
| 专题 | 沈阳自动化研究所_工业信息学研究室_工业控制系统研究室 |
| 推荐引用方式 GB/T 7714 | 魏立峰. 先进控制理论在软实时系统反馈调度中的应用研究[D]. 中国科学院沈阳自动化研究所. 中国科学院沈阳自动化研究所. 2004. |
入库方式： OAI收割
来源：沈阳自动化研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。