CAREER: Cooperative Virtual Machines: Mechanisms and Policies for Application-Aware Runtime Services

现代托管编程语言，从Java和C#到Java和Ruby，提供了一组令人信服的软件工程优势，而不是传统的C和C++语言。不幸的是，继续受到一系列有充分记录的性能问题的困扰。它们对内存的低效使用尤其会造成重大惩罚，对用这些语言构建的关键服务器软件的质量和容量造成严重影响。尽管进行了密集的研究和开发，但这些问题仍然顽固地没有解决。因此，程序员面临着一个困难的两难境地：选择一种安全可靠的托管语言，但又会遭受重大的性能损失，或者继续冒险使用C和C++。这个项目探索了一种新的方法，称为协作虚拟机，它通过改善程序员和托管语言运行时系统(虚拟机)之间的沟通和合作来解决这个问题。关键的想法是，有了额外的信息，虚拟机可以提供更高效的服务，因为它们是根据每个应用程序的需求进行定制的。该项目包括构建用于探索和量化内存性能的新工具，为大型服务器应用程序设计可配置的垃圾收集器，以及开发让程序员对数据结构的低级表示和管理进行更多控制的技术。内存利用率和性能的显著提高将使现有的计算基础设施(硬件和软件)能够向更多用户提供更高质量的服务。该项目的一个重要组成部分是改进的教学工具和技术，以帮助新程序员对这些复杂系统的性能进行推理。

Modern managed programming languages, from Java and C# to Javascript and Ruby, provide a compelling set of software engineering advantages over traditional languages like C and C++. Unfortunately, the continue to suffer from a range of well-documented performance problems. Their inefficient use of memory, in particular, imposes a significant penalty, with debilitating consequences for the quality and capacity of critical server software built in these languages. In spite of intensive research and development, these problems have remained stubbornly unsolved. As a result programmers face a difficult dilemma: choose a safe and secure managed language, but take a major performance hit, or continue taking their chances with C and C++.This project explores a new approach, called cooperative virtual machines, which attacks the problem by improving communication and cooperation between the programmer and the managed language runtime system (the virtual machine). The key idea is that with extra information, virtual machines can provide much more efficient services because they are customized to each application's needs. The project involves building new tools for exploring and quantifying memory performance, designing a configurable garbage collector for large server applications, and developing techniques to give programmersmore control over the low-level representation and management of data structures. Significant improvements in memory utilization and performance will allow existing computing infrastructure (hardware and software) to deliver higher quality services to more users. A crucial component of this project is improved pedagogical tools and techniques to help new programmers reason about the performance of these complex systems.