HCC: Medium: Hardware and Software Architectures for Next-Generation Mobile Platforms

在1991年发表的《21世纪的计算机》（The Computer for the 21st世纪）一文中，马克·韦瑟（Mark Weiser）描述了一个人们与智能信息设备互动的世界，在这个世界里，每个房间通常会有超过一百台这样的设备。他还描述了实现这一愿景所需的一些关键技术，包括“一个小电池将提供数天连续使用”的设备。从那时起，威瑟对无处不在的计算的到来的许多预测已经成为现实或被超越。现代计算系统在容量和性能方面的能力已经远远超出了Weiser的设想。然而，真正的无处不在的计算仍然远离我们，因为不断增长的能源需求和（相对）缓慢的电池技术进步限制了电池供电设备的寿命。本项目的目标是创建硬件和软件解决方案，以实现长寿命的移动的信息设备。非易失性存储器技术（例如磁性随机存取存储器）和双稳态显示器（例如电子墨水）的出现，通过使主存储器和显示器的静态功率接近零，大大改变了移动的设备的能量特征。该项目改变了微处理器的能量特征，通过调整其性能和能量来满足信息家电背景下典型用户交互模式的要求。这些模式包括查看/阅读显示屏（无计算）、与显示屏交互（最小计算）以及请求需要大量计算的任务，例如渲染新屏幕。处理器架构在具有类似于现代嵌入式处理器的能量特征的高性能模式、具有类似于微控制器的能量特征的低性能模式以及具有在不同模式之间的极快切换时间的超低功率空闲模式下操作，以便提供单个高性能处理器的假象。该项目创建了利用新微处理器的低功耗特性所需的软件接口，从而简化了低功耗信息设备的应用开发。该项目的最终目标是在电子书阅读器原型中展示新概念，该阅读器也是评估移动的信息设备能源需求的硬件测试平台，该项目将为开发电池寿命可按月而不是按天计量的移动的计算设备创造有利技术。该项目的成果将通过研究出版物传播，向研究界提供原型移动的平台，并对本科生和研究生进行设计和使用节能移动的设备的培训。移动的平台的能源需求的显著降低可导致世界信息技术基础设施的能源消耗的减少。不需要每天充电的移动的设备将帮助我们真正实现Mark Weiser的无处不在计算的愿景。

In his visionary 1991 article "The Computer for the 21st Century", Mark Weiser described a world in which people interact with smart information appliances, and where one would routinely have over a hundred such devices per room. He also described some of the key technologies needed to realize this vision, including devices where "a small battery will provide several days of continuous use." Since then, many of Weiser's predictions about the advent of ubiquitous computing have come to pass or have been exceeded. The capabilities of modern computing systems have far exceeded the requirements for Weiser's vision in terms of capacity and performance.However, truly ubiquitous computing still eludes us because the combination of increasing energy requirements and (relatively) slow progress in battery technology limits the lifetime of battery-powered devices. The goal of this project is to create hardware and software solutions to enable long-lifetime mobile information appliances.The emergence of non-volatile memory technologies (e.g. magnetic random access memory) and bi-stable displays (e.g. e-Ink) significantly alter the energy signature of mobile devices by enabling near-zero quiescent power for the main memory and display. This project alters the energy signature for the microprocessor by tailoring its performance and energy to the requirements of typical user interaction patterns in the information appliance context. These patterns include viewing/reading the display (no computation), interacting with the display (minimal computation), and requesting a task that requires significant computation such as rendering a new screen. The processor architecture operates in high-performance mode with an energy signature resembling a modern embedded processor, low performance mode with an energy signature resembling a microcontroller, and ultra low power idle mode with extremely fast switching times between the different modes so as to provide the illusion of a single high-performance processor. This project creates the software interfaces necessary to exploit the low power properties of the new microprocessor thus simplifying application development for low power information appliances. The final goal of the project is to demonstrate the new concepts in a prototype e-book reader that is also a hardware testbed for the evaluation of the energy requirements of mobile information appliances.This project will create enabling technologies for the development of mobile computing devices whose battery life can be measured in months, rather than days. The results of this project will be disseminated via research publications, by making a prototype mobile platform available to the research community, and by training undergraduate and graduate students in the design and implementation of energy-efficient mobile appliances.Given the billions of mobile devices currently in use worldwide, a significant reduction in the energy requirements for mobile platforms could lead to a reduction in the energy consumed by the world's information technology infrastructure. Mobile devices that do not need to be re-charged on a daily basis would help us truly realize Mark Weiser's vision of ubiquitous computing.