虚拟环境下Web服务器集群技术研究与实现

发布时间：2018-04-19 21:50

本文选题：虚拟化 + Web服务器集群　；参考：《国防科学技术大学》2014年硕士论文

【摘要】：随着互联网特别是移动互联网的不断普及,网络用户规模急剧上升,各类网络应用的可靠性和可用性面临极大挑战。为适应挑战,虚拟化等相关技术得到飞速发展和广泛应用。越来越多的企业将Web应用迁移到虚拟机上,借此提高资源利用率、提升系统可靠性、改善灵活性以及降低管理成本。在虚拟环境中搭建Web服务器集群系统来满足性能不断扩展的需要,是目前比较普遍的解决方案。但如果简单的将传统Web服务器集群搬至虚拟机,既无法充分展现虚拟化技术的优势,也很难克服传统Web服务器集群调度器性能瓶颈的缺点。论文从概念上和功能上将虚拟化技术与Web服务器集群技术相结合,提出了一种虚拟化环境下的集群综合性能管理模型XCluster。该模型采用分布式结构实现集群的负载监测、节点控制、任务调度和负载均衡。理论分析和实验结果表明,使用XCluster既能根据用户访问请求的总量以及宿主机的空闲资源来调度虚拟机,使得虚拟机在宿主机层按管理员定制的策略进行分布,又能根据各后端节点的负载状态分发用户请求实现虚拟机层的负载均衡。基于XCluster模型的Web服务器集群系统只需占用很少的网络通信量就能完成信息收集和命令下达。与使用Nginx作为调度器的集群相比,在高可用性方面,产生的请求失败数更少,系统可靠性更高,在负载均衡性能方面,活动节点负载随时间趋于一致,均衡效果较好,能适应大规模并发请求,而且集群规模随负载变化而动态调整,在一定程度上更加节约系统资源。
[Abstract]:With the increasing popularity of the Internet, especially the mobile Internet, the scale of network users has risen sharply, and the reliability and availability of various network applications are facing great challenges. In order to adapt to the challenges, virtualization and other related technologies have been rapidly developed and widely used. More and more enterprises migrate Web applications to virtual machines to improve resource utilization, improve system reliability, improve flexibility and reduce management costs. It is a common solution to build Web server cluster system in virtual environment to meet the need of continuous expansion of performance. However, if we simply move the traditional Web server cluster to virtual machine, we can not fully show the advantages of virtualization technology, and it is difficult to overcome the shortcomings of traditional Web server cluster scheduler performance bottleneck. In this paper, we combine virtualization technology with Web server cluster technology conceptually and functionally, and propose a cluster integrated performance management model XClusterin virtualization environment. The model uses distributed structure to realize load monitoring, node control, task scheduling and load balancing. Theoretical analysis and experimental results show that using XCluster can not only schedule virtual machines according to the total number of user access requests and the idle resources of the host, but also make the virtual machines distribute in the host layer according to the strategy customized by the administrator. Furthermore, the load balancing of virtual machine layer can be realized by distributing user requests according to the load state of each back-end node. The Web server cluster system based on XCluster model can complete the information collection and command delivery with only a small amount of network traffic. Compared with the cluster which uses Nginx as scheduler, in high availability, the number of request failures is less, the system reliability is higher, and the load of active node tends to be consistent with time in load balancing performance, and the balance effect is better. It can adapt to large scale concurrent requests, and the cluster size is adjusted dynamically with the change of load, which saves system resources to a certain extent.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP393.09

【参考文献】