CSR: Small: Accelerated ParalleX (APX) for Enhanced Scaling AMR based Science

智力优势：这个项目解决了Exascale并行计算机体系结构上应用程序的可伸缩性问题。可伸缩性的战略挑战之一是识别和利用新的并行形式，以及减少有效的细粒度并行执行的开销。该项目名为“Accelerated Parallex(APX)for Enhanced Scaling”，旨在将新的计算模型与传统多核平台中的FPGA硬件支持相结合，以实现显著的可伸缩性。这种方法特别适用于一类重要的基于自适应网格细化的中子星碰撞和伽马射线暴应用。NSF之前的资金支持了Parallex实验原型的开发。这个新的研究项目采用了这个模型。该框架提取了结构元数据中隐含的内在并行性，消除了大部分全局障碍，并释放了自适应控制以重叠多个计算阶段和中间通信，以实现延迟隐藏和避开竞争热点。研究了利用基于现场可编程门阵列的硬件技术来加速系统软件，以显著减少执行中的关键时间路径开销，并直接增强可伸缩性。实验设计包括同步原子、线程调度和队列以及主动消息驱动操作。此外，对于这类科学问题，更高精度的浮点运算对于解决尽可能小的黑洞等科学问题变得越来越重要。因此，FPGA技术将加速多精度浮点运算。这项研究如果成功，将推动数值相对论这一特定科学领域的发展，更广泛地说，将推动那些依赖AMR和强标度的科学和工程学科。它将通过将可用现场可编程门阵列技术创新地应用于一般计算科学和未来长期可扩展的系统设计，来推动近期的计算机系统科学。为此目的导出的性能模型可能被证明对于在复杂的多方面权衡空间中建立界限和敏感性的扩展的初步探索性调查是有价值的。更广泛的影响：APX的研究成果和资源将应用于向其他国家和国际校园现场分发的远程学习课程，以在短期内扩大其内容和高级主题部分，同时鼓励明年围绕其主题领域举办一门新的研究生级别的研讨会课程。路易斯安那州立大学将为人数不足的本科生和高中生设立暑期实习机会，贝奥武夫训练营将扩大到更多高中生。

Intellectual Merit:This project addresses scalability of applications on Exascale parallel computer architectures. Among the strategic challenges to scalability is identifying and exploiting new forms of parallelism as well as reducing overhead for effective fine grained parallelism execution. The project, "Accelerated ParalleX (APX) for Enhanced Scaling" project investigates combining a new model of computation with FPGA hardware support, in otherwise conventional multicore platforms, to realize significant gains in scalability. This approach is particularly applicable to the important class of adaptive mesh refinement based applications for colliding neutron stars and gamma ray bursts. Prior NSF funding supported the development of an experimental ParalleX prototype. That model is employed in this new research project. This framework extracts inherent parallelism implicit in structure meta-data, eliminates most global barriers, and releases adaptive control to overlap multiple phases of computation and intermediate communication for latency hiding and circumvention of contention hot spots. The research investigates the use of FPGA based hardware technology for accelerating system software to significantly reduce critical time path overhead in execution and directly enhance scalability. The experimental designs include synchronization atomics, thread scheduling and queues, and active message driven operations. In addition, for this class of science problems, higher precision floating-point arithmetic is becoming more important for such science questions as resolving the smallest possible black holes. FPGA technology will therefore accelerate multi-precision floating point arithmetic. This research, if successful, will advance the specific science domain of numerical relativity and, more broadly, those science and engineering disciplines relying on both AMR and strong scaling. It will advance near-term computer system science through an innovative application of available FPGA technology to general computational science and long-term future scalable system design. The performance model derived for this purpose may prove valuable for extended preliminary exploratory investigation for establishing bounds and sensitivities in a complex multi-faceted trade-off space. Broader Impact: The APX research results and resources will be applied to the distance-learning course distributed live to other national and international campuses to expand its content and extend its advanced topics section, in the short term, while motivating a new graduate level seminar course next year around its topic areas. Summer internships for under-represented undergraduate and high school students will be created at LSU and the Beowulf Bootcamp will be expanded for more high school students.