单选

在实时系统中,响应时间是衡量系统性能的最重要因素。任务调度的目的是缩短系统平均响应时间,提高系统资源利用率。以下关于嵌入式系统实时调度技术说法错误的是(28)。

  • A.抢占式调度具有实时性好,调度算法较简单,可保证高优先级任务的时间约束,上下文切换少等优点
  • B.非抢占式调度是指不允许任务在执行期间被中断,任务一旦占用嵌入式微处理器就必须执行完毕或自愿放弃
  • C.静态表驱动策略是一种离线调度策略,运行时刻表一旦生成后就不再发生变化
  • D.在任务运行过程中,采用静态优先级调度的任务优先级不会发生变化
参考答案
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