• 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 • Timing Analysis(WCET分析)
• 实时任务类型与约束模型 – 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
What is the thread? Java语言的一个重要特性是支持多线程的程 序设计,多线程是实现并发的一种有效手段。 线程是一个能独立执行自身指令的控制流 一个程序中可以同时运行多个相对独立的线 程,这样的程序称为多线程程序。 操作系统将CPU的执行划分为非常小的时间 片,根据一定的规则在不同的线程之间切换, 使每个线程都得到执行的机会