CXL

While it’s technically still the new kid on the block, the Compute Express Link (CXL) standard for host-to-device connectivity has quickly taken hold in the server market. Designed to offer a rich I/O feature set built on top of the existing PCI-Express standards – most notably cache-coherency between devices – CXL is being prepared for use in everything from better connecting CPUs to accelerators in servers, to being able to attach DRAM and non-volatile storage over what’s physically still a PCIe interface. It’s an ambitious and yet widely-backed roadmap that in three short years has made CXL the de facto advanced device interconnect standard, leading to rivals standards Gen-Z, CCIX, and as of yesterday, OpenCAPI, all dropping out of the race. And while the CXL...