arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2006.09864cs.DC
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随机调度中执行时间的概率模型

Probabilistic Models for the Execution Time in Stochastic Scheduling

Matheus Henrique Junqueira Saldanha

摘要:

程序的执行时间是计算机科学的许多领域中的关键元素,主要是那些实现良好性能的领域(例如,云计算中的调度)或可预测的调度(例如,满足嵌入式系统中的最后期限)是目标。尽管是随机变量,但在文献中,执行时间通常被视为确定性的,很少有作品利用其随机性;即使在这些作品中,底层分布也被假定为正态或均匀,没有特别的原因。在这项工作中,我们调查这些分布在各种机器和算法。一个数学问题出现时,处理样本的人口最低是未知的,所以很大一部分,这专着是专门为这样的问题。我们提出了几种不同的有效或计算成本低的方法来克服这个问题,这也适用于执行时间。这些方法进行了实验测试,结果表明,我们提出的推理方法的优越性。我们证明了存在长尾的执行时间分布,并得出结论,两个特定的概率分布是最适合所有的执行时间建模。虽然我们不讨论随机调度的直接应用,但我们希望促进概率执行时间的使用,以产生更好的结果,例如,任务调度。

英文摘要:

The execution time of programs is a key element in many areas of computer science, mainly those where achieving good performance (e.g., scheduling in cloud computing) or a predictable one (e.g., meeting deadlines in embedded systems) is the objective. Despite being random variables, execution times are most often treated as deterministic in the literature, with few works taking advantage of their randomness; even in those, the underlying distributions are assumed as being normal or uniform for no particular reason. In this work we investigate these distributions in various machines and algorithms. A mathematical problem arises when dealing with samples whose populational minimum is unknown, so a significant portion of this monograph is dedicated to such problem. We propose several different effective or computationally cheap ways to overcome the problem, which also apply to execution times. These methods are tested experimentally, and results point to the superiority of our proposed inference methods. We demonstrate the existence of execution time distributions with long tails, and also conclude that two particular probability distributions were the most suitable for modelling all execution times. While we do not discuss direct applications to stochastic scheduling, we hope to promote the usage of probabilistic execution times to yield better results in, for example, task scheduling.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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