The high demand for memory capacity in modern datacenters has led to multiple lines of innovation in memory expansion and disaggregation. One such effort is Compute eXpress Link (CXL)-based memory expansion, which has gained significant attention. To better leverage CXL memory, researchers have built several emulation and experimental platforms to study its behavior and characteristics. However, due to the lack of commercial hardware supporting CXL memory, the full picture of its capabilities may still be unclear to the community. In this work, we explore CXL memory's performance characterization on a state-of-the-art experimental platform. First, we study the basic performance characteristics of CXL memory using our proposed microbenchmark. Based on our observations and comparisons to standard DRAM connected to local and remote NUMA nodes, we also study the impact of CXL memory on end-to-end applications with different offloading and interleaving policies. Finally, we provide several guidelines for future programmers to realized the full potential of CXL memory

翻译：现代数据中心对内存容量的高需求推动了内存扩展与解耦技术的多线创新，其中基于Compute eXpress Link（CXL）的内存扩展技术备受关注。为更好地利用CXL内存，研究者构建了多种仿真与实验平台来研究其行为特征。然而，由于缺乏支持CXL内存的商业硬件，其完整能力图景可能仍不为学界所清晰认知。本文在最先进的实验平台上探索CXL内存的性能表征：首先，通过提出的微基准测试研究CXL内存的基本性能特征；其次，基于对本地与远程NUMA节点标准DRAM的观察与对比，进一步研究CXL内存在不同卸载与交错策略下对端到端应用的影响；最后，为未来开发者充分发挥CXL内存潜力提供若干指导准则。