Emerging hybrid memory systems that comprise technologies such as Intel's Optane DC Persistent Memory, exhibit disparities in the access speeds and capacity ratios of their heterogeneous memory components. This breaks many assumptions and heuristics designed for traditional DRAM-only platforms. High application performance is feasible via dynamic data movement across memory units, which maximizes the capacity use of DRAM while ensuring efficient use of the aggregate system resources. Newly proposed solutions use performance models and machine intelligence to optimize which and how much data to move dynamically; however, the decision of when to move this data is based on empirical selection of time intervals, or left to the applications. Our experimental evaluation shows that failure to properly configure the data movement frequency can lead to 10%-100% slowdown for a given data movement policy; yet, there is no established methodology on how to properly configure this value for a given workload, platform and policy. We propose Cori, a system-level tuning solution that identifies and extracts the necessary application-level data reuse information, and guides the selection of data movement frequency to deliver gains in application performance and system resource efficiency. Experimental evaluation shows that Cori configures data movement frequencies that provide application performance within 3% of the optimal one, and that it can achieve this up to 5x more quickly than random or brute-force approaches. System-level validation of Cori on a platform with DRAM and Intel's Optane DC PMEM confirms its practicality and tuning efficiency.
翻译:包含 Intel 的 Optane DC 持久性记忆等技术的新兴混合内存系统, 显示不同内存组成部分的存取速度和能力比率的差异。 这打破了为传统 DRAM 平台设计的许多假设和能力比率。 高应用性能通过记忆单位动态数据移动是可行的。 高应用性能是可行的, 使DRAM的能力最大化, 同时确保高效使用综合系统资源。 新的拟议解决方案使用性能模型和机器智能, 优化哪些和多少数据动态移动; 然而, 何时移动这些数据的决定, 取决于对时间间隔的实验性选择, 或是否留待应用。 我们的实验性评估表明, 正确配置数据移动频率可能导致特定数据移动政策减速10%- 100%; 然而, 在如何为特定的工作量、 平台和政策适当配置这一价值时, 没有既定的方法。 我们建议Cori, 系统级调调解解决方案, 确定和提取必要的应用级数据再利用信息, 指导数据移动频率的选择, 以在应用性能和系统资源效率方面实现增益。 实验性评估显示, Cori 配置数据移动速度比 级的频率在标准级别上, 3 级上, 级, Corrial- 级的频率可以实现最优化, 水平上, 。