外文翻译----文件系统虚拟化和服务网格数据管理(编辑修改稿)

外文翻译----文件系统虚拟化和服务网格数据管理(编辑修改稿)内容摘要：

fety (unreliable machines and works) that are typical in such environments. Last but not least, the management of data provisioning in a large, dynamic system also desires flexible control and automatic optimization of the remote data access, in order to deal with the plexity of providing data to many applications, to agilely adapt to the changing environments, and to deliver applicationdesired performance, security, and reliability. To address these challenges, this dissertation presents a twolevel data management system in which file system virtualization provides applicationtailored gridwide data access, and servicebased middleware enables autonomic management of the data provisioning. In particular, this system has made the following contributions: It provides ondemand, crossdomain data access transparently for unmodified applications and O/Ss based on userlevel virtualization of widely available O/Slevel distributed file systems (DFSs). It supports applicationtailored enhancements designed for gridstyle environments on several important aspects of remote data access, including performance, consistency, security, and reliability. It employs middleware services to achieve flexible and interoperable management of gridscale data provisioning, which is capable of controlling the lifecycles and configurations of dynamic data sessions based on application needs. It develops autonomic functions to automatically optimize the data management according to highlevel objectives, in order to reduce the plexity of managing data sessions and adapt them promptly to changing environments. Finally, the proposed system has been demonstrated, with thorough experimental evaluation, that it is efective and can significantly outperform conventional DFSbased approaches in gridstyle environments。 it has also been successfully deployed in a production grid system [2][3] for several years, supporting scientific tools and users from many disciplines. The data management system proposed in this dissertation is architected to address three important questions, which are discussed in the following subsections respectively. ApplicationTransparent GridWide Data Access The first question is, how to provide applicationtransparent gridwide data access? Grids difer from traditional distributed puting environments because of their distinct characteristics, ., widearea working, heterogeneous end systems, and disjoint administrative domains. These diferences bring new challenges to data management systems, and the technologies that are successful in localarea works (LAN), ., LAN file systems, cannot be directly applied in a grid environment. Instead, grid data management needs to specifically address these unique issues. Existing solutions allow applications to access grid data through the use of specialized APIs or libraries. However, the required modifications on application sources or binaries often place a burden upon the shoulders of end users and developers, and present a hurdle to applications that cannot be easily modified. Therefore, applicationtransparency is desirable to facilitate the deployment of a wide range of application。