SHF: Small: Managing Non-Determinism in Multithreaded Software and Hardware

SHF：小：管理多线程软件和硬件中的非确定性

• 批准号: 0916725
• 负责人: Mark Hill
• 金额: $ 50万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0916725&HistoricalAwards=false
• 关键词: SHF; Small; Managing; Non; Determinism

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."In the 21st century, the dominant computing platform has shifted to multicore chips that implement cache-coherent shared memory and run multi-threaded applications. Unfortunately, these chips do not provide a deterministic model to either software or hardware developers. Reasoning about and testing for multiple possible executions is much harder than reasoning about and testing for a single correct sequential execution, as was possible under the von Neumann model that dominated in the 20th century. Easing the burden of programming multicore chips is critical to provide society with the rapid, cost-effective performance gains that we have all come to expect. Moreover, broad impact requires practical solutions that do not ask industry to discard or rewrite billions of lines of existing general-purpose thread-based software.To this end, research under this proposal will develop solutions for managing non-determinism with alterative implementation approaches that provide complementary benefits and opportunities. (1) Work will expand techniques of recording executions for deterministic replay to improve replay parallelism and extend the scope of record/replay to hardware debugging and fault-tolerance. (2) Work will develop and advance a deterministic coherence model that eliminates a major source of non-determinism in shared-memory multiprocessor systems: memory races. (3) Work will develop both all-software and hardware-accelerated implementations of deterministic coherence, in part, through extensions to the Wisconsin GEMS simulation infrastructure. (4) Finally, work will explore rebuilding coherence upon a formal deterministic foundation. Broader impacts will include embodying the proposed work in public software releases (e.g., GEMS) as well as dissemination to students and through courses, talks, industrial affiliates, and commercial influence.

“该奖项是根据 2009 年美国复苏和再投资法案（公法 111-5）提供资金的。” 在 21 世纪，占主导地位的计算平台已转向实现缓存一致性共享内存并运行多线程应用程序的多核芯片。不幸的是，这些芯片没有为软件或硬件开发人员提供确定性模型。推理和测试多个可能的执行比推理和测试单个正确的顺序执行要困难得多，这在 20 世纪占主导地位的冯诺依曼模型下是可能的。减轻多核芯片编程的负担对于为社会提供我们所期望的快速、经济高效的性能提升至关重要。此外，广泛的影响需要实用的解决方案，而不是要求业界丢弃或重写现有的数十亿行基于通用线程的软件。为此，本提案下的研究将开发通过替代实施方法来管理非确定性的解决方案，从而提供互补的利益和机会。 (1) 工作将扩展确定性重放的记录执行技术，以提高重放并行性，并将记录/重放的范围扩展到硬件调试和容错。 (2) 工作将开发和推进确定性一致性模型，消除共享内存多处理器系统中非确定性的主要来源：内存竞争。 (3) 工作将部分通过威斯康星州 GEMS 模拟基础设施的扩展来开发确定性一致性的全软件和硬件加速实现。 (4) 最后，工作将探索在正式的确定性基础上重建一致性。更广泛的影响将包括在公共软件版本（例如 GEMS）中体现拟议的工作，以及通过课程、讲座、行业附属机构和商业影响力向学生传播。