ST-CRTS: A Coordinated Performance-Directed Attack on Underperformance

背景现代高性能系统长期未得到充分利用，不是因为它们的作业队列很短，而是因为每个任务只使用每个节点上可用电力的一小部分。编译的代码根本无法实现可用性能的合理部分，尽管学术界和旨在改善这种情况的研究实验室进行了多年的工作。部分性能差距是由于体系结构和设计造成的；然而，部分性能差距直接归因于优化编译器的设计。标准的优化技术无法发现和修复此类问题，部分原因是它们在过程级粒度进行操作，部分原因是补救方法要求编译器更改其优化该部分代码的方法，以使用另一种顺序或另一种转换方案。智力优势在这个项目中，PI将开发一种反馈驱动的自适应汇编工具，专门针对表现不佳的小区域的改进。为了使地区性方案发挥作用，他的团队将加强和重新制定两个强大的优化方案，即重新物化和重新关联，并重新确定其他方案的范围，以便它们在区域范围内而不是在全球范围内运作。积极的研究成果将在莱斯关于这一主题的研究生课程中讲授；由于该课程的教材在其他机构使用，因此材料将接触到广泛的受众。这个项目的工作将增加莱斯大学研究编译器的代码库，该代码库以源代码的形式免费分发给学术界和工业界的其他人。PI将利用当地资金和指导的研究项目的组合，直接将本科生纳入这项工作。

BackgroundModern high-performance systems are chronically underutilized not because their job queuesare short, but because each task uses just a small fraction of the power available on each node.Compiled code simply does not achieve a reasonable fraction of the available performance, despiteyears of work in academia and in research labs that aimed to improve the situation. Some of theperformance gap is due to architecture and design; however, a portion of it is directly attributableto the design of optimizing compilers. Standard optimization techniques fail to discover and fix such problems, in part because they operate at a procedure-level granularity and in part because the remedy requires the compiler to change its approach to optimizing that part of the code to use another order or another transformation scheme. Intellectual Merit In this project, the PI will develop a feedback-driven adaptive compilation harnessthat specifically targets improvements in small regions of underperformance. To make the regionalscheme work, his team will enhance and reformulate two powerful optimizations, rematerialization andreassociation, and re-scope others so that they operate on a regional rather than a global scope.Broader ImpactThis project will directly support graduate education at Rice. The positive researchresults will be taught in a Rice graduate course on the subject; the material will reach a broadaudience because the teaching materials for the course are used at other institutions. The work inthis project will add to the code base for the Rice University research compiler, which is distributed free ofcharge in source-code form to others in both academia and industry. The PI will use a combination oflocal funds and directed research projects to include undergraduates directly in this work.