摘要
针对数控系统的混合任务调度以及高可靠性的特点,提出一种基于软件容错模型的实时调度算法(FT-MT)。该算法在系统运行前预先分配替代版本的执行区间,使得替代版本在其截止期内尽可能地推迟执行,为主版本的完成提供了最大的可执行时间。同时,为了避免主版本的早期失败对后续任务的影响,增加了主版本的可执行规则,提高了主版本可执行性的预测精度。仿真实验表明,与同类算法相比,FT-MT算法在提高数控系统容错能力方面更为有效。
According to the characteristics of hybrid task set and high dependability of numerical control systems, a fault tolerant real time scheduling algorithm based on software fault-tolerant model was proposed to dispose of system transient faults. In order to provide the maximal execution time for the primaries, the FT-MT algorithm reserves time intervals as late as possible for all the alternates before their deadlines. At the same time, for the sake of preventing early failures in execution from giving rise to failures in the subsequent tasks, an executive rule for primaries was added into the FT-MT algorithm which improved the predictive quality of the primaries remarkably. The simulation experiments show that the FT-MT algorithm has much better fault resilience than that of the well-known algorithms so far.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2010年第15期1809-1815,共7页
China Mechanical Engineering
基金
国家科技重大专项(2009ZX04009-022
2009ZX04009-013)
关键词
数控系统
调度算法
软件容错
主版本
替代版本
numerical control system
scheduling algorithm
software fault-tolerant
primary version
alternate version
