Abstract: In the era of big data, applications in various data centers, such as AI and cloud comput- ing, have increasingly urgent needs for storing and computing large-scale data, while the access overhead of massive data has become a major bottleneck limiting system performance. In addition, existing data center architectures suffer from issues of low memory utilization and limited memory expansion capabilities. Memory pool systems based on new memory semantic interconnect protocols offer a range of characteristics, including high bandwidth, low energy consumption, large capacity, and scalability, providing new insights into addressing these issues and exerting a significant impact on future data center architectures. This paper discusses and compares the features and operating modes of five new memory semantic interconnect protocols: OpenCAPI, Gen-Z, CCIX, NVLink, and CXL. It analyzes their roles in constructing memory pool systems and further explores their application research. Both in industry and academia, CXL currently attracts the highest attention and holds the best development prospects among memory semantic interconnect technologies. Therefore, we specifically emphasize the characteristics, advantages, and research status of CXL. Finally, we analyze the challenges still faced by memory pool systems based on new memory semantic interconnect protocols and offer prospects for future research in this direction.

Key words: data center architecture, memory-semantic interconnect, memory pool, compute express link