Programming-Language Structures for Representing and Optimizing Operating-System Resources

用于表示和优化操作系统资源的编程语言结构

• 批准号: 9633438
• 负责人: Gerald Sussman
• 金额: $ 10万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-15 至 1998-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9633438&HistoricalAwards=false
• 关键词: Programming; Language; Structures; Representing; Optimizing

This research project seeks to demonstrate that fundamental operating system services and resources can and should be represented directly in the natural linguistic structures of advanced programming languages. A component of this effort is to develop aggressive optimisation strategies making this modelling practical and efficient. The central question underlying the research is: how can the benefits of advanced programming languages be brought to bear upon current systems-programming practice? Modern computer applications are most commonly written in C, a language well- known for its lack of support for writing modular, robust programs. C has no module system, allows dangerous "casting" of data types, violates abstraction barriers, provides no garbage- collection support for automatic storage management, has no concurrency operators, and generally exposes the details of the underlying machine to the programmer. It is not defined in terms of a mathematically sound underlying semantics. As a result, modern software is fragile, error-prone, and difficult to build, maintain or reuse. Modern programming languages, such as the ML family of languages, provide much more support to the programmer for writing large, robust programs. Unfortunately, these languages are not yet practical tools for implementing real-world systems software. In practice, programs written in these languages are slow, use large amounts of memory, and have awkward interfaces to OS services. Providing access from programs written in these languages to the machine resources, in ways that are natural to the language, should help to address these shortcomings. This research enables new optimisations and makes available new models to the programmer, allowing systems programs to be written that exploit the expressive power of advanced programming languages. A service kernel provides access to the underlying machine resources in a way that is tightly integrated, both in architecture and in implem entation, with advanced languages. The research issue is to investigate the architecture of an operating system that is symbiotic, not with C, but with a modern programming language, and to develop technologies for exploiting the tight integration of the OS and the compiler to provide efficient, high-level services. The kernel is being developed in ML, on two hardware platforms: a bare Intel PC system, and a wireless, mobile "personal digital assistant" with limited on-board resources. ***

这一研究项目试图证明，基本的操作系统服务和资源可以而且应该直接用高级编程语言的自然语言结构来表示。这项工作的一个组成部分是开发积极的优化策略，使这种模型实用而有效。这项研究的核心问题是：高级编程语言的好处如何应用于当前的系统编程实践？现代计算机应用程序最常见的是用C编写，这是一种众所周知的语言，因为它缺乏对编写模块化、健壮的程序的支持。C没有模块系统，允许危险的数据类型“强制转换”，违反了抽象障碍，没有为自动存储管理提供垃圾收集支持，没有并发操作符，并且通常向程序员公开底层机器的细节。它不是根据数学上合理的潜在语义来定义的。因此，现代软件是脆弱的、容易出错的，并且难以构建、维护或重用。现代编程语言，如ML语言系列，为程序员编写大型、健壮的程序提供了更多的支持。不幸的是，这些语言还不是实现现实世界系统软件的实用工具。在实践中，用这些语言编写的程序速度很慢，使用大量内存，并且与操作系统服务的接口很笨拙。以语言自然的方式提供从用这些语言编写的程序对机器资源的访问，应该有助于解决这些缺点。这项研究实现了新的优化，并为程序员提供了新的模型，允许编写利用高级编程语言的表达能力的系统程序。服务内核以一种与高级语言紧密集成的方式提供对底层机器资源的访问，无论是在体系结构上还是在实现上。研究问题是研究操作系统的体系结构，它不是与C语言共生的，而是与现代编程语言共生的，并开发利用操作系统和编译器的紧密集成来提供高效、高级服务的技术。内核是在两个硬件平台上用ML开发的：一个是裸露的Intel PC系统，另一个是无线的、移动的“个人数字助理”，板载资源有限。***