Service Rate Control of Tandem Queues With Power Constraints
Service Rate Control of Tandem Queues With Power Constraints
复制标题
DOI：
10.1109/tac.2017.2678109
复制
发表时间：
2017-03
影响因子：
6.8
通讯作者：
L. Xia;Daniel Miller;Zhengyuan Zhou;N. Bambos
中科院分区：
文献类型：
--
作者：
L. Xia;Daniel Miller;Zhengyuan Zhou;N. Bambos
在本文中，我们研究了具有功率约束的串联队列服务率的最优控制。服务器的服务率由分配给该服务器的功率决定。系统的总功率是固定的。系统成本由两部分组成，反映队列拥塞的持有成本和反映服务器功耗的运营成本。优化目标是找到服务器之间的最优功率分配策略，以使系统平均成本最小化。我们将此问题表述为具有约束动作空间的马尔可夫决策过程。应用基于灵敏度的优化理论来研究此问题。当运营成本具有线性或凹形形式时，推导出了最优服务率的充要条件以及可行域顶点的最优性。进一步开发了一种迭代算法来找到最优服务率。即使成本函数具有一般形式，该算法也可能效果良好。还研究了对具有多个服务器的一般串联队列的扩展。最后，我们在不同的参数设置下进行了数值实验，以展示本文的主要思想。
In this paper, we study the optimal control of service rates of a tandem queue with power constraints. The service rate of a server is determined by the power allocated to that server. The total power of the system is fixed. The system cost is comprised of two parts, the holding cost reflecting the congestion of queues and the operating cost reflecting the power consumed at servers. The optimization objective is to find the optimal power allocation policy among servers, which can minimize the system average cost. We formulate this problem as a Markov decision process with a constrained action space. Sensitivity-based optimization theory is applied to study this problem. The necessary and sufficient condition of optimal service rates, and the optimality of the vertexes of the feasible domain are derived when the operating cost has a linear or concave form. An iterative algorithm is further developed to find the optimal service rates. This algorithm may work well even when the cost function has a general form. The extension to general tandem queues with many servers is also studied. Finally, we conduct numerical experiments under different parameter settings to demonstrate the main idea of this paper.