平行有限缓冲系统时间安排:延迟反馈下的最佳决定 (Scheduling in Parallel Finite Buffer Systems: Optimal Decisions under Delayed Feedback)

Scheduling decisions in parallel queuing systems arise as a fundamental problem, underlying the dimensioning and operation of many computing and communication systems, such as job routing in data center clusters, multipath communication, and Big Data systems. In essence, the scheduler maps each arriving job to one of the possibly heterogeneous servers while aiming at an optimization goal such as load balancing, low average delay or low loss rate. One main difficulty in finding optimal scheduling decisions here is that the scheduler only partially observes the impact of its decisions, e.g., through the delayed acknowledgements of the served jobs. In this paper, we provide a partially observable (PO) model that captures the scheduling decisions in parallel queuing systems under limited information of delayed acknowledgements. We present a simulation model for this PO system to find a near-optimal scheduling policy in real-time using a scalable Monte Carlo tree search algorithm. We numerically show that the resulting policy outperforms other limited information scheduling strategies such as variants of Join-the-Most-Observations and has comparable performance to full information strategies like: Join-the-Shortest-Queue, Join-the- Shortest-Queue(d) and Shortest-Expected-Delay. Finally, we show how our approach can optimise the real-time parallel processing by using network data provided by Kaggle.

翻译：平行排队系统中的决策安排是一个根本性问题,它支撑着许多计算和通信系统,例如数据中心集群、多路径通信和大数据系统的工作路线,因此产生了一个根本性问题。实质上,排程员将每个到达的工作岗位都映射到一个可能各异的服务器上,同时力求实现优化目标,如负载平衡、低平均延迟或低损失率。这里找到最佳时间安排决定的一个主要困难是,排程员仅部分地观察其决定的影响,例如,通过延迟确认所服务的工作。在本文中,我们提供了一个部分可观测(PO)模型,在延迟确认信息的有限信息的情况下,记录平行排队列系统中的时间安排决定。我们为这个程序系统提供了一个模拟模型,以便利用一个可缩放的蒙特卡洛树搜索算法,实时找到一个接近最佳的排程政策。我们从数字上表明,由此产生的政策超越了其他有限的信息排程战略,例如合并(Mest-Oserviews)的变式,其性与全面信息战略相似,例如:联合-最短网络-最短的处理方法,我们如何使用最短-最短-最短-最短-最短-最短-最短-最短-最短-最短-最短-最短-最短-最后显示-最短-最能显示-最后显示-最后显示-显示-显示-显示-最后-我们-最能显示-最短-最后-最后-显示-最短-最短-最短-最短-最后-最后-显示-最短-显示-显示-显示-最后-显示-显示-最短-显示-最后-最后-显示-最后-最后-最后-显示-显示-最后-最后-显示-最后-显示-显示-最后-显示-显示-最后-最后-最后-最后-显示-最后-最后-显示-显示-最后-最后-最后-最后-显示-显示-显示-最后-最后-显示-最接近-最后-最后-最后-最后-最后-最接近-最接近-最后-最后-最接近-显示-最后-最后-最后-最后-最后-最后-显示-最后-最后-显示-最后-最后-最后-最后-最后-最后-最后-最后-最后-最后-最后-最后-显示-显示-模拟-最后-最后-最接近-A-