Error-tolerant Stream Processing System Design (ESP-SD)

未来CMOS集成中的能量耗散和故障率预计将要求放弃传统的系统可靠性，转而采用跨应用程序、运行时支持和系统架构控制错误的方法。流处理应用程序的商业利益相关者，如多媒体分析和检索以及网页排名系统，已经感受到在不断增长的用户需求下系统级扩展和鲁棒性不足的压力。虽然这样的应用程序可以容忍一定的不精确性（错误）在他们的计算，这方面是目前不用于系统的可扩展性和resilience.The ESP-SD项目将推导出理论，方法，和一套原型工具的可扩展调整的计算和错误传播的流处理应用程序运行在一个故障生成的计算环境。这将通过以下创新来实现：* 多媒体和链接数据分析算法中的容错随机模型（用于音频/视频匹配、语义多媒体检索、网页排名系统等）;* ESP-SD的目标是与传统处理相比（在同一平台下），吞吐量和能量扩展高达两个数量级，应用结果在随机意义上是可靠的。也就是说，ESP-SD中的所有加速、节能和可靠性机制都是为了最大限度地减少应用中的“预期”误差，而不是最坏情况下的误差。该项目将产生实际的设计，以展示其影响，在“影响摘要”和“影响途径”中提供了关于JES的例子。

The energy dissipation and fault rates in future CMOS integration are expected to require the abandonment of traditional system reliability in favour of approaches that control errors across the application, runtime support, and system architecture. Commercial stakeholders of stream processing applications, such as multimedia analysis & retrieval and webpage ranking systems, already feel the strain of inadequate system-level scaling and robustness under increasing user demand. While such applications can tolerate certain imprecision (errors) in their calculations, this aspect is currently not used for system scalability and resilience.The ESP-SD project will derive theory, methods, and a prototype set of tools for scalable adjustment of computation and error-propagation in stream processing applications operating under a fault-generating computing environment. This will be achieved via the following innovations: * stochastic models of error tolerance in algorithms for multimedia and linked-data analytics (used in audio/video matching, semantic multimedia retrieval, webpage ranking systems, etc.);* new forms of accelerated error-tolerant computation within numerical stream processing libraries;* opportunistic designs for compiler and runtime support offering graceful resilience to runtime errors.ESP-SD aims for up to two orders of magnitude of throughput and energy scaling against conventional processing (under the same platform), with application results that are reliable in a stochastic sense. That is, all mechanisms for acceleration, energy saving and reliability in ESP-SD are geared towards minimizing the "expected" error in applications, and not the worst-case error. The project will derive practical designs demonstrating its impact, examples of which are provided in the "Impact Summary" and the "Pathways to Impact" on JeS.