CSR-EHS: Integrated Memory Allocation and Scheduling for Real-Time Embedded Systems

CSR-EHS：实时嵌入式系统的集成内存分配和调度

• 批准号: 0720797
• 负责人: Alexander Dean
• 金额: $ 18万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0720797&HistoricalAwards=false
• 关键词: CSR; EHS; Integrated; Memory; Allocation

Many of the conveniences of modern life are made possible by embedded computing systems. This project is developing new methods to make such systems use their limited resources more efficiently, increasing performance, reducing costs and energy requirements. Modern general-purpose computers (PCs, servers, etc.) owe most of their high processing speed to caches. These memory system components fetch data from the slow (but inexpensive) main memory for the fast processor before it even realizes it needs it. Unfortunately the performance offered by caches is very difficult to guarantee, greatly complicating the prediction of a program's worst-case performance. This prediction is essential for a broad class of embedded and control systems ? those with real-time requirements. Such systems must respond to inputs before a deadline elapses or else something will fail. Hence such systems must be over-provisioned to cover the ?margin of ignorance?, raising costs and energy requirements.This project is developing methods to provide memory accesses as fast as with a cache, but without any of the timing uncertainty, making this technology suitable for real-time systems. The research team uses a unified approach which cuts across compilers, operating systems, and computer architecture to create a much more efficient solution than possible by considering the problems separately. The fundamental insight is that by limiting preemption among threads, one can reduce the total memory required, allowing more data to be stored in fast memory. This speeds thread execution, allowing further reduction of preemptions (and hence memory requirements) leading to a repeatable, virtuous cycle.

嵌入式计算系统使现代生活的许多便利都成为可能。 该项目正在开发新的方法，以使此类系统更有效地使用其有限的资源，从而提高性能，减少成本和能源需求。现代通用计算机（PC，服务器等）的大部分高处理速度都归功于缓存。这些内存系统组件从慢速（但价格便宜）的快速处理器中获取数据，甚至在意识到它需要它之前。不幸的是，Caches提供的性能很难保证，这极大地使对程序最差的性能的预测变得复杂了。该预测对于广泛的嵌入式和控制系统至关重要？具有实时要求的人。此类系统必须在截止日期之前响应输入，否则某些事情将失败。 因此，必须过多地进行此类系统以涵盖无知的边缘，提高成本和能源需求。该项目正在开发方法以与缓存一样快速提供内存访问，但是没有任何时间不确定性，因此这项技术适合实时系统。研究团队使用一种统一的方法，该方法可以跨编译器，操作系统和计算机体系结构削减，从而通过分别考虑问题来创建比可能更有效的解决方案。 基本的见解是，通过限制线程之间的抢先，可以减少所需的总内存，从而使更多数据存储在快速内存中。这会加快线程执行的速度，从而进一步降低预先抢先（以及内存要求），从而导致可重复的，良性的周期。