® 实时调度 李曦 llxx@ustc.edu.cn 计算机系计算机应用研究室
实时调度 李曦 llxx@ustc.edu.cn 计算机系计算机应用研究室
内容提要 ·实时任务约束模型 -Assumptions about task timing,interaction,。。。 。人 任务调度算法Scheduling Algorithm Scheduling mode and selection function ·Timeliness:deadline,worst response time,。。。 Efficiency:average response time,makespan -Prioritized goals Temporal predictability first,performance second 。 可调度分析Schedulability Test Prediction of worst-case behavior 基于CPU利用率(workload analysis) for preemptive and strictly periodic tasks? -WCRT(Response time analysis) ·for preemptively feasible task sets with D≤T ·多处理器调度：优先级贪心调度，Pfair调度 ·Timing Analysis(WCET分析)
内容提要 • 实时任务约束模型 – Assumptions about task timing，interaction，。。。 • 任务调度算法Scheduling Algorithm – Scheduling mode and selection function • Timeliness：deadline，worst response time，。。。 • Efficiency：average response time，makespan – Prioritized goals • Temporal predictability first，performance second • 可调度分析Schedulability Test – Prediction of worst-case behavior – 基于CPU利用率(workload analysis) • for preemptive and strictly periodic tasks？ – WCRT(Response time analysis) • for preemptively feasible task sets with D ≤ T • 多处理器调度：优先级贪心调度，Pfair调度 • Timing Analysis(WCET分析)
参考文献 USTC 各a 《嵌入式系统设计·嵌入式CPS系统基础》， 嵌入式系统设计一横入式 信息物理系基础 第2版，2011 -Peter Marwedel(TU Dortmund教授)。译错多⑧ Giorgio C Buttazzo,RETIS Lab,TeCIP Insitute, Pisa,Italy Hard Real-Time Computing Systems:Predictable GergChinsoo Hard Real-Time Scheduling Algorithms and Applications,第三版， Computing Systems 2011 Multiprocessor Scheduling for Real-Time Systems,2015 REAL-TIE SYSTBI6 Multiprocessor Scheduling for Real-Time Systems 0.5. 种e 3/100
参考文献 • 《嵌入式系统设计·嵌入式CPS系统基础》， 第2版，2011 – Peter Marwedel（TU Dortmund教授）。译错多 • Giorgio C Buttazzo，RETIS Lab, TeCIP Insitute， Pisa, Italy – Hard Real-Time Computing Systems: Predictable 3/100 – Hard Real-Time Computing Systems: Predictable Scheduling Algorithms and Applications，第三版， 2011 – Multiprocessor Scheduling for Real-Time Systems，2015
Multiprocessor/distributed Multiprocessors systems is a set of autonomous processors which have software to coordinate them self and share resources Share the same clock - Share the same main memory o Distributed systems is a set of autonomous processors that are connected by a network and which have software to coordinate themself or share resources -No shared memory.Message passing communication. -A clock for each processor
Multiprocessor/distributed • Multiprocessors systems – is a set of autonomous processors which have software to coordinate them self and share resources – Share the same clock – Share the same main memory • Distributed systems – is a set of autonomous processors that are connected by a network and which have software to coordinate themself or share resources – No shared memory. Message passing communication. – A clock for each processor
Multiprocessors/MultiCore Arch. 》 homogeneous processors processors have the same computing capability and run task at the same rate heterogeneous processors PE PE PE PE ● Cluster Heterogeneous MPSoCs Shared -ARM的big.LITTLE架构 Shared Shared Cortex-A15 MPCore+Cortex-A7 气月9。tur年可 ReGourco ·理论上可以使电池的使用寿命延长高达70%
Multiprocessors/MultiCore Arch. • homogeneous processors – processors have the same computing capability and run task at the same rate • heterogeneous processors • Cluster Heterogeneous MPSoCs – ARM的big.LITTLE架构 • Cortex-A15 MPCore+Cortex-A7 • 理论上可以使电池的使用寿命延长高达70%