基於軟體定義網路的雲端資料中心上 網路效能和能源消耗最佳化研究

Abstract

近年來，隨著雲端運算(Cloud Computing)的快速發展，資料中心扮演了越來越重要的角色提供大量的計算與服務。對雲端供應者而言，如何減少資料中心的能源消耗以及如何增加資料中心網路效能成為重要的課題用來節省開銷並得到最大利益。在這篇論文中，我們討論有關於節能以及提高網路效能的議題，提出「動態即時的流量和虛擬機器搬遷演算法」，在節能的條件下有效率的增加網路效能。

在本文，我們提出的「動態即時的流量和虛擬機器搬遷演算法」由兩個主要的概念所構成：(1) 藉由快速流量搬遷機制 (Traffic-aware Flow Migration, TA-FM) 及 (2) 考量節能及網路拓撲的虛擬機器搬遷機制 (Energy-and-Topology aware VM Migration, ETA-VMM)，前者在軟體定義網路裡提供了更快速的流量繞徑控制；後者則是在原本節能的虛擬機器搬遷演算法裡加入網路的考量。本文也結合兩個模擬器NS2和CloudSim的模擬數據來驗證我們提出的正確性及優越性。

Minimizing energy consumption and improving performance in datacenters are critical to cost-saving for cloud operators, but traditionally, these two optimization objectives are treated separately. VM migration policies are frequently provided by the cloud controller for energy saving, while routing algorithm is adopted to improve network performance by the network controller. However, the interaction between cloud controller and network controller is not considered. Therefore, this paper presents an unified solution combining two strategies, flow migration and VM migration, to maximize throughput and minimize energy, simultaneously. Traffic-aware flow migration (FM) is first incorporated in dynamic reroute (DENDIST), evolving into DENDIST-FM, in a software-defined network (SDN) for improving throughput and avoiding congestion. Second, given energy and topology information, VM migration (ETA-VMM) can help reduce traffic loads and meanwhile save energy. Our experimental result indicates that compared to previous works, the proposed method can improve throughput by 50.0% on average with only 3.2% energy overhead. Accordingly, the unified flow-and-VM migration solution has been proven effective for optimizing throughput and energy in SDN-based cloud datacenters.