XPS:CLCCA:LigHTS: Lagging-Hardware Tolerant Systems" in the system.

随着可扩展并行计算的到来，数以千计的设备被集中连接和管理。在这个时代，面临着一个新的挑战：性能故障；由于硬件故障、软件错误和配置错误等大规模管理问题，系统的性能经常低于预期。这个项目针对一个被忽视的性能故障原因：落后的硬件--与其规范相比其性能显著下降的硬件。许多报告表明，单个落后的硬件很容易级联，导致整个集群的性能崩溃。在这里，并行性未被开发，生产力降低，系统未得到充分利用，能源被浪费。LIGHTS项目的目标是将计算系统转变为落后的硬件容忍系统。LIGHTS项目将给社会带来许多直接的好处；来自许多领域(科学、医疗、商业、教育、军事和政府)的用户越来越多地使用大规模的存储和计算服务。在这里，可预测的性能是成功的关键，在这种背景下，落后的硬件容忍计算是一个关键因素。LIGHTS项目由三个主要目标组成。第一个目标是滞后--硬件数据分析和仪器。为了提高未来并行系统的健壮性，关键是研究现代硬件所表现出的滞后特性，并设计新的工具方法来收集部署中滞后硬件的情况。第二是滞后故障系统分析。重要的是严格分析滞后硬件(包括磁盘、网络、处理器)对当前部署的系统的影响。其结果将揭示设计缺陷，并为部署的系统应该如何发展提供有价值的重新评估。最后是LIGHTS原则、设计和实现。需要建立滞后硬件容忍计算的基本原则，并将这些原则应用于构建跨越分布式存储、计算框架、操作和运行时系统的跨层LIGHTS系统原型。

With the advent of scalable parallel computing, thousands of devices are connected and managed collectively.  This era is confronted with a new challenge: performance failure; systems often perform worse than expected due to large-scale management issues such as hardware failures, software bugs, and configuration mistakes.  This project targets one overlooked cause of performance failure: "lagging hardware" -- hardware whose performance degrades significantly compared to its specification.  Many reports indicate that a single lagging hardware can easily cascade and make the performance of a whole cluster collapse.  Here, parallelism is unexploited, productivity is reduced, the system is underutilized, and energy is wasted. The goal of the LigHTS project is to transform computing systems into Lagging-Hardware Tolerant Systems.  The LigHTS project will bring many direct benefits to the society; users from many areas (science, healthcare, business, education, military, and government) increasingly use large-scale storage and computation services.  Here, predictable performance is a key to success, and in this context lagging-hardware tolerant computing is a critical ingredient. The LigHTS project consists of three major objectives.  The first is lagging-hardware data analysis and instrumentation. To improve the robustness of future parallel systems, it is crucial to study lagging characteristics exhibited by modern hardware and to devise new instrumentation methodologies that can collect cases of lagging hardware in deployment.  The second is lagging-failure system analysis.  It is important to rigorously analyze the impact of lagging hardware (including disk, network, processor) to currently deployed systems. The results will unearth design flaws and provide valuable reevaluations of how deployed systems should evolve.  The last is LigHTS principles, design, and implementation.  There is a need to establish foundational principles of lagging-hardware tolerant computing and apply the principles in building prototypes of cross-layer LigHTS systems spanning distributed storage, computing framework, operating and runtime systems.