摘要
在集群系统中,为有安全需求的实时应用提供安全保障得到了广泛关注,但将实时应用的安全需求与调度算法相结合的研究并不多.文中提出了一种异构集群系统中安全关键实时应用的2阶段调度策略——TPSS.该策略综合考虑了任务的安全需求与时间限制.在TPSS的第1阶段,提出了一种自适应调度算法DSRF,当系统负载较重时,DSRF算法能在保证任务安全需求的基础上,通过降低新到任务和等待队列中任务的安全级别来提高任务的调度成功率.相反,当系统负载较轻时,DSRF算法能在保证系统具有较高调度成功率的基础上充分利用任务在截止期前的空闲时间提高新任务的安全级别.在TPSS的第2阶段,提出了一种新的算法FMSL,用来为所接收任务提供较为公平的安全服务,同时进一步提高了任务的整体安全级别.文中通过大量的模拟实验对TPSS策略与DSRF算法、SAEDF算法和RF算法进行了比较.实验结果表明,TPSS策略优于其它方法,使系统具有较强的安全性与灵活性.
Increasing attention has been directed towards the issue of security service for real-time applications with security requirements on clusters.In this paper,we propose a novel two-phase scheduling strategy TPSS which takes timing constraints and security needs of tasks into consideration.In the first phase,the authors propose a novel algorithm DSRF to schedule real-time tasks.When the system is in heavy burden,DSRF is able to degrade the security levels of new tasks and tasks waiting in local queues so as to enhance schedulability.On the contrary,when the system is in light burden,DSRF is capable of employing slack time to adequately improve the security qualities of new tasks.In the second phase,a new algorithm FMSL is proposed to minimize the difference of security levels of accepted tasks and further improve the security levels of these tasks on the whole,which degrades the probability of the applications being attacked.The authors compare TPSS,DSRF,SAEDF and RF by extensive simulation experiments.The experimental results indicate that TPSS significantly outperforms other algorithms and improves the security and flexibility of the cluster systems.
出处
《计算机学报》
EI
CSCD
北大核心
2010年第12期2364-2377,共14页
Chinese Journal of Computers
基金
国家"八六三"高技术研究发展计划项目基金(2008AA7070412)
国家自然科学基金(60673082)
教育部全国优秀博士学位论文作者专项基金(200084)资助~~
关键词
调度
异构集群
实时
安全关键
截止期
scheduling
heterogeneous clusters
real-time
security-critical
deadline
