CSR:Small:Parallelism and Concurrency in Scripting Languages

在过去的十年中，人们对所谓的“动态”或“脚本”编程语言的兴趣激增，这些语言强调程序员的生产力，但可能会牺牲运行时性能。 在其他应用程序中，脚本语言是许多基于Web和移动的计算的核心。 随着使用的增加，以及多核处理器的激增，通过并行执行来提高这些语言的性能将是不可避免的压力。 不幸的是，并行脚本的最新技术水平并没有跟上并行体系结构的发展。 虽然许多脚本语言支持异步处理来自外部世界的事件，但以程序员为中心的功能，如动态类型，使得事件处理程序和主程序--或者主程序的多个方面--在现代处理器的不同内核上高效地同时执行。这个项目的目标是建立一个详细的理解脚本语言设计和并行执行的性能。 这个目标是通过两个主要任务来实现的：（1）最小化在并行执行时保护语言实现所需的开销，以及（2）量化不同数据共享和内存一致性模型的边际成本。 大部分工作都是用Ruby脚本语言完成的，Ruby脚本语言广泛用于Internet服务器开发。 该方法将利用事务存储器、多读同步和高性能数据结构的最新发展，该项目将直接有助于研究生和本科生的培训，并有助于高级和入门课程的课程设置。 更广泛地说，在主流脚本语言中对并行性的有效支持可以预期在政府、工业、科学、艺术和娱乐的所有计算机应用中产生生产力的显著提高。

The past decade has seen an explosion of interest in so-called "dynamic" or "scripting" programming languages, which emphasize programmer productivity at the possible expense of run-time performance. Among other applications, scripting languages are central to much web-based and mobile computing. With increasing use, and with the proliferation of multicore processors, there will be inevitable pressure to improve the performance of these languages through parallel execution. Unfortunately, the state of the art in parallel scripting has not kept pace with parallel architecture developments. While many scripting languages support asynchronous handling of events from the external world, programmer-centric features, like dynamic typing, make it very difficult for event handlers and the main program-- or multiple aspects of the main program -- to execute efficiently and simultaneously on separate cores of a modern processor.The goal of this project is to build a detailed understanding of the tradeoffs between scripting language design and the performance of parallel execution. This goal is accomplished through two main tasks: (1) minimizing the overhead necessary to safeguard the language implementation in the face of parallel execution, and (2) quantifying the marginal cost of different models of data sharing and memory consistency. The bulk of the work takes place in the Ruby scripting language, widely used for Internet server development. This approach will leverage recent developments in transactional memory, read-mostly synchronization, and high-performance data structures.This project will contribute directly to the training of students at both the graduate and undergraduate level, and to curricula for courses at both the advanced and introductory level. More broadly, effective support for parallelism in mainstream scripting languages can be expected to produce significant improvements in productivity across the full range of computer applications, in government, industry, science, the arts, and entertainment.