CSR: SHF: Small: Programming Language, Runtime System, and Architecture Support for Reliability in Intermittent, Energy-Harvesting Computing Devices

CSR：SHF：小型：间歇性能量收集计算设备可靠性的编程语言、运行时系统和架构支持

• 批准号: 1526342
• 负责人: Brandon Lucia
• 金额: $ 50万
• 依托单位: Carnegie-Mellon University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1526342&HistoricalAwards=false
• 关键词: CSR; SHF; Small; Programming; Language

Emerging energy-harvesting computing devices (EHDs) run on energy extracted from their environment and are poised to be the key enabler of next-generation wearables, implantable medical devices, and the Internet of Things (IoT) applications. However, software on an EHD can only execute intermittently, as energy is available. When power fails (10 to 100 times per second) the EHD turns off and reboots, requiring software on EHDs to span multiple periods of execution interrupted by power failures. Unfortunately, today's software development tools and practices do not address intermittence, and frequent interruptions cause unexpected and incorrect system behavior. Intermittence is a barrier to the widespread adoption of EHDs for many high-value applications and limits EHDs to use by experts only.This proposal addresses the fundamental challenges of intermittence by introducing the Persistent- Channel-Based (PCB) programming and execution model. PCB provides a new, simpler way to write software that is robust to intermittence. PCB also describes a new way to execute that software with high reliability, despite intermittence. By simplifying the process of writing software for EHDs and making intermittent execution reliable, PCB makes EHDs accessible to all potential system builders and developers.Just as the maturation of programming and execution models for embedded computer systems spawned industries around new embedded applications (e.g., the quantified-self project and in-home sensing), the development of the ideas in this project propels the same transformation for EHDs. PCB will enable researchers, individuals, and commercial players to create novel EHD-based applications that in the past could only be tediously purpose-built by expert researchers. The impact of this work is expected to transcend the technical outcomes of the research.The primary technical outcomes in PCB are novel approaches to writing and executing software. Programs are composed of tasks using a novel task-graph control-flow model that eliminates control-flow discontinuities due to intermittence. PCB's novel channel-based memory model together with channel access control, ensures that memory remains consistent. PCB simplifies a program?s reasoning progress because it persistently tracks the execution through the task graph and channel access control prevents a task from modifying its inputs, ensuring correctness as the task repeatedly executes to completion. PCB cuts across layers of the system stack, with language, compiler, runtime, and architecture support using a language that enables programmers to use simple expressions. The compiler maps programs to operations in PCB's runtime system which in turn implements tasks and channels, providing the guarantees relied on by the PCB language. Hardware and architecture support for channels and tasks, provides similar guarantees with novel hardware support, eliminating the overhead of the software runtime system. Encouraging preliminary findings support the idea that PCB's tasks and channels makes reasoning about intermittent computation simpler and that PCB eliminates correctness issues in several actual EHD applications.

新兴的能量收集计算设备 (EHD) 依靠从环境中提取的能量运行，有望成为下一代可穿戴设备、植入式医疗设备和物联网 (IoT) 应用的关键推动者。然而，由于能量可用，EHD 上的软件只能间歇性地执行。当断电（每秒 10 到 100 次）时，EHD 会关闭并重新启动，从而要求 EHD 上的软件能够跨越因断电而中断的多个执行周期。不幸的是，当今的软件开发工具和实践并不能解决间歇性问题，频繁的中断会导致意外和不正确的系统行为。间歇性是许多高价值应用广泛采用 EHD 的障碍，并且限制了 EHD 只能由专家使用。该提案通过引入基于持久通道 (PCB) 的编程和执行模型来解决间歇性的基本挑战。 PCB 提供了一种新的、更简单的方法来编写对间歇性具有鲁棒性的软件。 PCB 还描述了一种以高可靠性执行该软件的新方法，尽管存在间歇性。通过简化为 EHD 编写软件的过程并使间歇执行变得可靠，PCB 使所有潜在的系统构建者和开发人员都可以使用 EHD。正如嵌入式计算机系统的编程和执行模型的成熟催生了围绕新嵌​​入式应用程序（例如，量化自我项目和家庭传感），该项目中思想的发展推动了 EHD 的相同转变。 PCB 将使研究人员、个人和商业参与者能够创建基于 EHD 的新颖应用，而这些应用在过去只能由专家研究人员进行繁琐的专门构建。这项工作的影响预计将超越研究的技术成果。PCB 的主要技术成果是编写和执行软件的新颖方法。程序由使用新颖的任务图控制流模型的任务组成，该模型消除了由于间歇性而导致的控制流不连续性。 PCB 新颖的基于通道的内存模型与通道访问控制相结合，确保内存保持一致。 PCB 简化了程序的推理进度，因为它通过任务图持续跟踪执行情况，通道访问控制可防止任务修改其输入，从而确保任务重复执行完成时的正确性。 PCB 跨越系统堆栈的各层，提供语言、编译器、运行时和架构支持，使用的语言使程序员能够使用简单的表达式。编译器将程序映射到PCB运行时系统中的操作，而PCB运行时系统又实现任务和通道，提供PCB语言所依赖的保证。对通道和任务的硬件和架构支持，通过新颖的硬件支持提供类似的保证，消除了软件运行时系统的开销。令人鼓舞的初步结果支持这样的观点：PCB 的任务和通道使间歇计算的推理变得更简单，并且 PCB 消除了几个实际 EHD 应用中的正确性问题。

项目成果

A Reconfigurable Energy Storage Architecture for Energy-harvesting Devices

• DOI: 10.1145/3296957.3173210
• 发表时间: 2018-02-01
• 期刊: ACM SIGPLAN NOTICES
• 作者: Colin, Alexei;Ruppel, Emily;Lucia, Brandon
• 通讯作者: Lucia, Brandon