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

Mark Weiser在他1991年发表的富有远见的文章《21世纪的计算机》中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，每个房间通常都会有100多台这样的设备。他还描述了实现这一愿景所需的一些关键技术，包括“一块小电池就能连续使用几天”的设备。从那时起，威瑟关于无处不在计算到来的许多预测都变成了现实，或者已经被超越。现代计算系统的能力在容量和性能方面已经远远超出了威瑟的愿景的要求。然而，真正的普适计算仍然无法实现，因为不断增加的能源需求和(相对)缓慢的电池技术进步限制了电池供电设备的寿命。该项目的目标是创建硬件和软件解决方案，以实现长寿命移动信息设备。非易失性存储器技术(如磁随机存取存储器)和双稳态显示器(如e-Ink)的出现显著改变了移动设备的能量特征，使主存储器和显示器能够实现近零静态功率。该项目通过调整微处理器的性能和能量来改变微处理器的能量特征，以满足信息家电环境中典型用户交互模式的要求。这些模式包括查看/读取显示器(无计算)、与显示器交互(最小计算)以及请求需要大量计算的任务，例如渲染新屏幕。处理器体系结构在高性能模式下操作，具有类似于现代嵌入式处理器的能量签名；低性能模式，具有类似微控制器的能量签名；以及超低功率空闲模式，具有在不同模式之间的极快切换时间，从而提供单个高性能处理器的错觉。该项目创建了开发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家电的应用程序开发。该项目的最终目标是在原型电子书阅读器中演示新概念，该原型电子书阅读器也是评估移动信息设备能源需求的硬件试验台。该项目将为移动计算设备的开发创造使能技术，其电池寿命可以用几个月而不是几天来衡量。该项目的成果将通过研究出版物传播，通过向研究界提供移动平台原型，并通过培训本科生和研究生设计和实施节能移动设备来传播。鉴于目前全球正在使用的数十亿台移动设备，移动平台能源需求的显著减少可能会导致世界信息技术基础设施的能源消耗减少。不需要每天充电的移动设备将帮助我们真正实现Mark Weiser关于无所不在计算的愿景。

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.