Bandwidth Management for Time-critical Applications in Multi-tenant Data Centers

• Main Authors: Jiann-Min Ho, 何鍵民
• Other Authors: Ming-Syan Chen
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/tvp6e7

博士 === 國立臺灣大學 === 電機工程學研究所 === 105 === Modern Internet services, like web search, online banking, social networks and various recommendations, rely on cloud or production data centers to process large-scale and ever-growing data distributed in a large number of compute and storage nodes. Many of these services are time-critical implying that the corresponding applications running in the data centers are subject to meet service-level objectives (SLOs), e.g., deadlines. In the distributed environments, network performance is a leading factor for the time-critical applications meeting SLOs. As these data centers are often shared amongst multiple tenants (running diverse applications), the share nature implies that each tenant could receive variable network performance, leading to deviating SLOs. Bandwidth management in multi-tenant datacenters is challenging. At one end, tenants need predictable underlying network performance; at the other end, providers (or operators) need high efficiency, e.g., for paying off immense investments in building datacenters. Furthermore, inter-tenant fairness could be another desirable property in the public cloud for instance. In this dissertation, we study how to improve inter-tenant and intra-tenant efficiency subject to predictability and fairness for time-critical applications in multi-tenant data centers. We first consider inter-tenant efficiency. As bandwidth isolation leads to predictability, we focus on a popular use case where tenants and providers adopt the resource descriptive interface of virtual cluster, which guarantees bandwidth isolation. Based on observations on existing reservation systems, we propose an approach to improve the efficiency of data centers while servicing multiple tenants in an online fashion. However, spare bandwidth resources left in the reservation systems lead to inefficiency. To this end, we further propose a market-clearing mechanism to further improve the inter-tenant efficiency while achieving the desired fairness among tenants. Then, we consider the impact of efficient inter-tenant bandwidth allocation on the intra-tenant efficiency. More specifically, we observe suboptimal application throughput of existing deadline-aware flow schedulers under efficient inter-tenant bandwidth allocation schemes. Accordingly, we propose a new deadline flow scheduling scheme for a tenant running its time-critical applications under efficient inter-tenant bandwidth allocation. For evaluating our proposed approaches, we conduct extensive simulations based on synthetic and real-world traces. The results show that inter-tenant efficiency can be improved over existing reservation systems and tenants'' application throughput is increased under efficient inter-tenant bandwidth allocation.