【正文】 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 ?exible 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。因此，本論文提出了一種新的基于服務(wù)的數(shù)據(jù)管理辦法，自主管理和自動優(yōu)化配置的數(shù)據(jù)按照這樣高層次的目標。 服務(wù)為基礎(chǔ)的管理自主數(shù)據(jù) 第三個問題是，如何管理數(shù)據(jù)在網(wǎng)格尺度系統(tǒng)配置與動態(tài)變化的環(huán)境？ GVFS中方法的基礎(chǔ)上，數(shù)據(jù)會話可以啟動需求和獨立定制的應(yīng)用程序。為了提供所需的性能，安全性和可靠性，一個網(wǎng)格，數(shù)據(jù)供應(yīng)需求要按照優(yōu)化應(yīng)用程序的行為和需要。 本論文提出了一個用戶級 DFS的虛擬化，即網(wǎng)格虛擬文件系統(tǒng)（ GVFS中），為應(yīng)用程序透明的網(wǎng)格數(shù)據(jù)訪問。 ?最后，建議的制度已經(jīng)證明，以徹底的實驗評價，認為它是有效的，能顯著優(yōu)于常規(guī) 。 首先，應(yīng)用程序和數(shù)據(jù)資源的多樣性促使供應(yīng)解決方案，可以透明地部署，無需改變現(xiàn)有的經(jīng)營 系統(tǒng)（海外 / SS）和修改應(yīng)用程序源代碼或二進制代碼。這些資源通常有不同的硬件配置（例如， CPU速度和結(jié)構(gòu)，內(nèi)存大小，磁盤帶寬和容量）和軟件設(shè)置（例如，操 作系統(tǒng)和圖書館），而應(yīng)用程序也有不同的特性（如數(shù)據(jù)訪問模式）和需要（如需要的數(shù)據(jù)訪問性能，安全性和可靠性）。在這些系統(tǒng)中常見的是，應(yīng)用程序和數(shù)據(jù)都分布在資源跨行政區(qū)劃和廣域網(wǎng)。 他們分布在不同的機構(gòu)和廣域連接網(wǎng)絡(luò)，提供的計算能力和存儲能力，支持處決許多應(yīng)用程序。 ?它支持網(wǎng)格式環(huán)境設(shè)計的應(yīng)用程序定制的增強幾個重要方面，遠程數(shù)據(jù)訪問，包括性能，一致性，安全性和可靠性?，F(xiàn)有 的解決方案通過專門的使用 Grid數(shù)據(jù) API 或庫 ， 允許應(yīng)用程序訪問。 總之，這種方法提供建議 GVFS中回答了第一個問題 ，即 透明網(wǎng)寬未修改的應(yīng)用和 O /不銹鋼通過數(shù)據(jù)訪問用戶級別的 DFS的虛擬化。特別是，增強設(shè)計網(wǎng)格式的環(huán)境是虛擬化層時提供 GVFS中，這包括可定制的磁盤高速緩存的高性能數(shù)據(jù)和多線程接入，應(yīng)用程序所需的數(shù)據(jù)一致性協(xié)議的一 致性效率，強并網(wǎng)兼容的安全保障網(wǎng)范圍內(nèi)的數(shù)據(jù)訪問和可靠性協(xié)議支持應(yīng)用程序透明的故障檢測和恢復(fù)。這些要求往往超出了最終用戶和系統(tǒng)的能力，甚至管理員。這種自主管理是適用于幾個重要的方面，包括數(shù)據(jù)會話緩存配置，數(shù)據(jù)復(fù)制和會話重定向。 from a resource provider39。 FILE SYSTEM VIRTUALIZATION AND SERVICE FOR GRID DATA MANAGEMENT 1. INTRODUCTION Computations are being increasingly larger scale, in terms of both size and geographical and administration distribution. Examples include scientific grids [1] which harness resources among several institutions for coordinated problem solving, and enterprise information systems that aggregate eforts from multiple sites for collaborative development. Common in these systems is that applications and data are distributed on resources across administrative boundaries and widearea works. Such envir