Application-Specific Memory System Optimizations using Programmable Memory Controllers

片外存储器子系统是现代计算机系统中一个重要的性能和功耗瓶颈，需要一个存储器控制器，它可以通过精心编排处理器和主存储器之间的数据移动来克服存储器时间和资源限制。该项目的目标是通过使用可编程主存储器控制器实现特定于应用程序的存储器系统优化，从而提高未来计算机系统的性能、能源效率和服务质量，从而解决这一需求。为了实现可编程主存储器控制器的这一愿景，该项目解决了从可编程处理单元的硬件设计到新型存储器管理算法的固件实现的所有挑战。采用自动机器学习和搜索技术来快速达到针对不同应用程序和单个应用程序的不同阶段定制的高性能控制算法。开发了特定于应用程序的内存管理算法，范围从地址映射、命令调度、DRAM电源管理到纠错码和内存压缩。由此产生的特定于应用程序的存储系统的灵活性预计将对未来计算机系统的性能和能源效率产生直接影响，并对科学、技术和整个社会产生巨大的积极影响。架构和软件创新通过发表的论文以及在主要会议上关于可编程控制器和特定应用程序的内存控制器算法的教程传播到更广泛的研究社区。该项目的教育部分包括(1)对研究生和本科生进行计算机体系结构方面的培训，(2)将可编程内存控制器和下一代内存系统集成到教学大纲中的内存系统课程，以及(3)为本科生提供内存控制器设计经验，作为现有计算机体系结构课程的一部分。

The off-chip memory subsystem is a significant performance and power bottleneck in modern computer systems, necessitating a memory controller that can overcome memory timing and resource constraints by carefully orchestrating data movement between the processor and main memory. The goal of this project is to address this need by enabling application-specific memory system optimizations using a programmable main memory controller, thereby improving the performance, energy-efficiency, and quality-of-service of future computer systems. To realize this vision of programmable main memory controllers, the project addresses challenges all the way from the hardware design of programmable processing units to the firmware implementation of novel memory management algorithms. Automated machine learning and search techniques are employed to quickly arrive at high-performance control algorithms customized to different applications, and to different phases of a single application. Application-specific memory management algorithms ranging from address mapping, command scheduling, and DRAM power management to error-correcting codes and memory compression are developed.The flexibility of the resulting application-specific memory systems is expected to have a direct impact on the performance and energy-efficiency of future computer systems, with tremendous positive fallout to science, technology, and society as a whole. Architecture and software innovations are disseminated to the broader research community through published papers, as well as tutorials on programmable controllers and application-specific memory controller algorithms at major conferences. The educational component of the project involves (1) training both graduate and undergraduate students in computer architecture, (2) a memory systems course that integrates programmable memory controllers and next-generation memory systems into the syllabus, and (3) a memory controller design experience for undergraduates as part of the existing computer architecture curriculum.