GEMSCLAIM: GreenEr Mobile Systems by Cross LAyer Integrated energy Management

个人计算目前面临着从台式机向通过平板电脑、智能手机和类似终端设备访问的移动的服务的快速趋势。在计算能力方面，今天的手持设备类似于20世纪80年代的Cray-2超级计算机。由于更高的计算负载（例如，经由多媒体应用）和各种无线电接口（诸如WiFi、3G和LTE），现代终端变得越来越耗能。例如，在当今的智能电话上的单个UMTS上传或视频记录过程可能消耗多达1. 5瓦，即最大设备功率的大约50%。在不久的将来，更高的数据速率和流量，先进的媒体编解码器和图形应用程序将要求更多的能量比电池可以提供。与此同时，功率密度限制可能会导致22 nm CMOS及以下的“暗硅”占据相当大的份额。显然，需要突破性的能源优化，远远超出传统技术，如DVFS（动态电压和频率缩放）和暂时未使用的组件的省电。GEMSCLAIM项目旨在引入新的方法来减少这种“对能源的贪婪”，从而改善用户体验并为移动的计算带来新的机会。重点是三种新颖的方法：（1）跨层能量优化，范围从操作系统上的编译器向下到目标HW平台，（2）基于能量感知服务水平协议（SLA）和能量敏感的可调参数对能量优化的异构多核平台的有效编程支持，以及（3）将能量感知引入到虚拟平台中，以便动态地定制用于能量优化和在线能量监视和计费的HW架构。GEMSCLAIM将在这些领域提供新的方法和工具，并将通过基准和硬件平台原型量化潜在的能源节约。

Personal computing currently faces a rapid trend from desktop machines towards mobile services, accessed via tablets, smartphones and similar terminal devices. With respect to computing power, today 's handheld devices are similar to Cray-2 supercomputers from the 1980s. Due to higher computational load (e.g. via multimedia apps) and the variety of radio interfaces (such as WiFi, 3G, and LTE), modern terminals are getting increasingly energy hungry. For instance, a single UMTS upload or a video recording process on today 's smartphones may consume as much as 1.5 Watts, i.e. roughly 50% of the maximal device power. In the near future, higher data rates and traffic, advanced media codecs, and graphics applications will ask for even more energy than the battery can deliver. At the same time, the power density limit might lead to a significant share of "Dark Silicon" at 22nm CMOS and below. Obviously, disruptive energy optimizations are required that go well beyond traditional technologies like DVFS (dynamic voltage and frequency scaling) and power-down of temporarily unused components. The GEMSCLAIM project aims at introducing novel approaches for reducing this "greed for energy", thereby improving the user experience and enabling new opportunities for mobile computing. The focus is on three novel approaches: (1) cross layer energy optimization, ranging from the compiler over the operating system down to the target HW platform, (2) efficient programming support for energy-optimized heterogeneous Multicore platforms based on energy-aware service level agreements (SLAs) and energy-sensitive tunable parameters, and (3) introducing energy awareness into Virtual Platforms for the purpose of dynamically customizing the HW architecture for energy optimization and online energy monitoring and accounting. GEMSCLAIM will provide new methodologies and tools in these domains and will quantify the potential energy savings via benchmarks and a HW platform prototype.