The Key Technology Research Ofgreen Desktop Cloud

With the concern of the market for green computing and IT management cost, desktop virtualization has become the focus of attention of both academia and indestry, which following the server virtualizatiion and cloud computing field, is another new technological innovations. As the highest degree of maturity of virtualization computing model, desktop virtualization is the highest energy efficiency, a new computatioal model of the most energy-feeicient. The leading market research firm, the Gartner forecast, as a first strategic technology, global desktop virtualization market size in2012will reach$2.5billion; will reach$10billion by2014. According to the white paper "estimates of cloud computing in china", the desktop virtualization market in2014will reach5billion yuan and an annual growth rate of30%.Traditionally, industry or academia view desktop virtualization as an extension of a server virtualization that can provide a desktop service by increasing connecting agent, desktop management, destop host server and other components on the top of server virtualization layer. The supply of desktop by calling the interface of the underlying server virtualization API. The Citrix Xendesktop and the VMWare View are this kind of technology. The biggest feature of this type of technology is the new to support depends on the underlying server virtualization platform. Deployment of such technology and product platform is suitable for large data centers; it requires high-speed network support, expensive shared storage components to achieve high availability, dynamic provisioning and other advanced features. There is some problems1) Server virtualization for the CPU-intensive applications; the desktop loads are IO-intensive applications. Server virtualization based structure can not improve the efficiency of desktop virtualization applications;2)Requiring higher configuare of network, storage and hardware that are equel to the server virtualization deployment;3) Very high procurement costs, management costs and maintenance costs, is eight times the cost of traditional PC.4) Very complex management and need professional knolwdge and skills.This research finds an optimal balance point as the basic staring point from desktop virtualization’s four aspects-performace, cost, accessibility and complexity. Technology and performance indicators include:1) Rapid dynamic desktop delivery features;2) based on the high feasibility of the low-cost hardware;3) Supporting on-demand linear scaling mechanism; the cost of virtual desktop is close to or even lower normal PC.4) Can be deployed in existing network environment and hardware resources, without the need for re-planning infrastructure. In response to above problems to be solved, a new desktop management strategy and desktop image life cycle was proposed in the third chapter by analysising traditional windows desktop deployment, management, life cycle, combined with virtual environment features. As a basis of the study of the image management mechanism in the virtual environment and virtual desktop refresh strategy, batch updates patches in a short time, greatly reducing the time and effort in the maintenance of desktops can be achieved through proposed mechanisms and strategies.In order to achieve the rapid cloning and instantiate desktops, the four chapter introduces the remote memory access mechanism for desktop system. On the beginning of this chapter, the user desktop data access behavior was tracked for one week and access patterns was analysised. According to access patterns, Lazing-caching mechanism was proposed in this chapter that can effectively sperate user data from operating system. Experimenets show that this mechamism can help images increase the flexibility, and great savings storage space.Dynamic perception of the virtual desktop resources is prerequisites of accurate, on-demand delivery. System in chapter five descrives the strategies and models of resource-dependend perception in virtual environments, and the three key resources for the virtual machin server.Chapter six proposed a distributed virtual file system based on cheap storage devices DAS, which accelerate desktop image transmission in low-speed storage devides by using a proxy based on the NFS. Through this file system, normal DAS storage system can provide high-speed, reliable, on-demand desktop images services via Ethernet. Chapter seven introduces the whole system design and implementation. This chapter focuses on the eomponents and the principle of Desktop Grid, Desktop Plant, and Desktop Aagent.