SHF:Small:Disciplined Approximate Programming for Energy-Efficient Computing

这项研究旨在使计算系统更节能，从而延长移动设备的电池寿命，并降低最终用户和数据中心的能源账单。关键的方法是识别和利用计算中允许近似结果或偶尔出错的部分，并利用这种灵活性来节省能源。虽然牺牲精度最初对计算机来说似乎是不可想象的，但它适用于许多应用程序的能源密集型部分，例如与多媒体、传感或随机模拟相关的程序。在允许一定的近似值的同时，仍然必须坚持只允许程序员特别注释为“近似值”的数据和代码是不精确的。此外，这项研究还将开发监控和实施“服务质量”的技术，在这种情况下，“服务质量”指的是近似对可观测输出的影响。这项研究必然跨越传统计算执行堆栈的几个层。最好的节能方式是通过新颖的硬件，由于近似性，这种硬件可以通过电压调整或更低的高速缓存刷新率等各种方法来节省能源。但只有更高级别的抽象才知道哪里适合近似，因此我们需要语言设计和语言实现来将此信息传递给硬件。此外，程序员还需要软件开发工具来调试和分析利用近似值的应用程序。这项研究的结果将包括在计算机体系结构、编程语言设计和实现以及软件工具方面的进展。

This research aims to make computing systems more energy-efficient, leading to longer battery life for mobile devices and lower energy bills for end users and data centers. The key approach is to identify and exploit portions of computations where approximate results or occasional errors are allowable and use this flexibility to save energy. While sacrificing precision may initially seem unthinkable for computers, it is appropriate for the energy-intensive portions of many applications, such as programs related to multimedia, sensing, or random simulation. While allowing some approximation, one must still insist that only data and code specifically annotated as "approximate" by the programmer is allowed to be imprecise. Moreover, this research will develop techniques for monitoring and enforcing "quality of service", which in this context means the impact that approximation has on the observable output.The research necessarily crosses several layers of the conventional computing execution stack. The best way to save energy is via novel hardware that, thanks to approximation, can save energy via various means such as voltage scaling or lower cache refresh rates. But only higher levels of abstraction know where approximation is appropriate, so we need language design and language implementation to communicate this information to the hardware. In addition, programmers need software-development tools for debugging and profiling applications that leverage approximation. The results of this research will include advances in computer architecture, programming language design and implementation, and software tools.