CSR: Small: Software Cache Memory Managements with Reconfigurable Hardware Emulators

随着多核系统成为主要的计算平台，高效的缓存管理对系统性能和功耗的影响比以前更加重要。一个有效的方法是使用软件缓存管理（SCM）和硬件支持来管理共享的最后一级缓存，因为复杂的SCM可以适应多核处理器上缓存使用的复杂场景。缺乏丰富的相关信息，使软件能够对不同配置下的缓存性能进行推理，这是配置管理中一个亟待解决的关键问题。该项目研究了使用轻量级和可重构硬件缓存模拟器（rce）来扩展SCM的功能。有了这种新的硬件支持，通过rce不断监控缓存使用情况的复杂SCM算法被开发出来。这些单片机算法旨在通过关闭未使用的缓存部分来提高缓存电源效率，优化多核处理器的缓存分区，以及改进软件控制的缓存映射以提高缓存利用率。该研究将提高系统性能，电源效率，以及使用大型共享缓存的多核处理器的笔记本电脑，台式机和服务器计算机的性能可预测性。它可能会对工业处理器设计产生影响，包括轻量级rce以及丰富的单片机算法。本课程亦会引入新的教材，让学生透过动手实验来学习多核高速缓存管理。

As multi-core systems become the major computing platform, efficient cache management is even more crucial to system performance and power efficiency than before. An effective approach is to use software cache management (SCM) with hardware supports to manage shared last-level cache, because sophisticated SCM may adapt to the complex scenarios of cache usage on multi-core processors.A critical and unsolved issue in SCM is the lack of rich and relevant information for software to reason about cache performance under different configurations. The project investigates the use of lightweight and Reconfigurable hardware Cache Emulators (RCEs) to extend the capability of SCM. With this new hardware support, sophisticated SCM algorithms that constantly monitor cache usage through RCEs are developed. Those SCM algorithms aim to improve cache power efficiency by turning off unused cache portion, optimize cache partitioning for multi-core processors, and improve software-controlled cache mapping to improve cache utilization.The research will improve system performance, power efficiency, and performance predictability for laptop, desktop and server computers using multi-core processors of large shared caches. It may make an impact on industry processor design to include lightweight RCEs as well as enrich SCM algorithms. It will also introduce new educational materials for students to study multicore cache management through hand-on experiments.