CAREER: Fine-Grained Operating System Components for Storage

现代计算机操作系统由数百万行性能关键代码组成，其中大部分代码与硬件紧密耦合，其中大多数错误都可能扩展为安全漏洞，其行为从根本上影响其托管的每个应用程序。因此，操作系统本身就很难编程，而正确使用操作系统又非常重要，这就减缓了操作系统研发的步伐。新的编程方法可以帮助打破这种僵局，使系统更容易教授、理解、编程和正确使用。本研究计划发展一种新的基于元件的文件系统与磁碟储存设计。它特别关注文件系统一致性，即确保磁盘以正确格式包含正确信息的过程。所有文件系统组件都使用变更描述符数据结构进行通信，这是一种软件更新的泛化，允许独立的文件系统和磁盘结构表达依赖关系。更改描述符被导出到应用程序，允许它们实现以前无法表达的一致性策略。最终的设计将通过分解公共代码使文件系统更容易开发，通过一流的一致性支持提高存储系统的健壮性，并导致对系统崩溃更具弹性的新应用程序设计。该项目将产生一个文件系统组件支持库和一系列组件，以及几个示例应用程序，包括一些为课堂使用而设计的应用程序。所有的代码都是免费和广泛分发的。

A modern computer operating system comprises millions of lines of performance-critical code, much of it tightly coupled to the hardware, where most any error can be expanded into a security vulnerability, and whose behavior fundamentally impacts every application it hosts. Thus, perating systems are both inherently hard to program and critically important to get right, which has slowed the pace of operating systems research and development. New programming methodologies can help break this impasse, leading to systems that are easier to teach, understand, program, and get right. This research program develops a new component-based design for file systems and disk storage. Its particular focus is file system consistency, the process that ensures that disks contain correct information in the correct format. All file system components communicate using change descriptor data structures, a generalization of soft updates that allows independent file systems and disk structures to express dependencies. Change descriptors are exported to applications, allowing them to implement previously-inexpressible consistency policies. The resulting design will make file systems easier to develop by factoring out common code, improve storage system robustness through first-class consistency support, and lead to new application designs that are far more resilient to system crashes. The project will produce a file system component support library and an array of components, as well as several sample applications, including some designed for classroom use. All of the code will be freely and widely distributed.