Collaborative Research: AF: Medium: Adventures in Flatland: Algorithms for Modern Memories

计算机行业正处于数据存储技术的革命之中，这迫使人们对用于在计算机中移动数据的算法进行重大重新评估。每一代新存储硬件都需要对这些算法构建块有新的理论理解。这样的理论改进对计算机科学的其他领域产生了深远的影响，包括数据库和文件系统，甚至网络、操作系统和机器学习。该项目旨在开发算法解决方案，以利用存储技术的这种地震转变。该团队考虑了新硬件技术（如非易失性存储器和增加的并行性）对算法性能的三个影响：(1)延迟和带宽之间的差距更小，(2)多核心技术在缓存上引入了共享效果，(3)内存层次结构不遵循严格嵌套的标准模型。该小组正在调查：(a)并行高速缓存分配和高带宽内存调度和分配中的算法问题；(b)由不同输入/输出成本模型引起的数据结构问题，包括计算成本和/或持久性成本因素；(c)扩展到流和半流模型，其中算法除了传统的小池随机访问内存外，还具有一定数量的顺序可访问的工作内存；(d)新的有向图I/ o高效算法。该团队正在继续致力于跨系统和算法的社区建设，包括创建、指导和/或运行两个新的会议，并组织关于非易失性存储器和存储理论的研讨会。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The computer industry is in the midst of a revolution in data-storage technology that is forcing a major reevaluation of the algorithms used for moving data through the computer. Every new generation of storage hardware has required a new theoretical understanding of these algorithmic building blocks. Such theoretical improvements have had a profound impact on other fields of computer science, including databases and file systems, and even networks, operating systems, and machine learning. This project aims to develop the algorithmic solutions needed to exploit this seismic shift in storage technology.The team considers three impacts on algorithm performance that arise from new hardware technology such as nonvolatile memories and increased parallelism: (1) there are smaller gaps between levels in latency and in bandwidth, (2) many-core technologies introduce sharing effects on caches, and (3) memory hierarchies do not adhere to a standard strictly nested model. The team is investigating: (a) algorithmic problems in parallel-cache allocation and high-bandwidth-memory scheduling and allocation; (b) data structural problems that arise from different I/O cost models, including those that factor in the computational cost and/or the cost of durability; (c) extensions to the streaming and semi-streaming models, where algorithms have some amount of sequentially accessible working memory in addition to the traditional small pool of randomly accessible memory; (d) new I/O-efficient algorithms for directed graphs. The team is continuing community-building efforts to span systems and algorithms, including founding, steering, and/or running two new conferences and organizing workshops on the theory of non-volatile memory and storage.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.