4 facts filed under Host interfaces and protocols: 1 read in the original source and 3 reported by a second source. Each was checked against the source’s own words, so its figures appear there, and each names where it comes from. The idea is taught in Part 10, The Future of Flash.
Primary sources
The CXL 4.0 specification doubles bandwidth from 64GT/s to 128GT/s.
Secondary sources
ServeTheHome says AMD EPYC Genoa arrived in 2022 with CXL support for Type-3 memory expansion devices.
ServeTheHome says Intel’s official CXL support did not come until 5th Gen Intel Xeon Processors (Emerald Rapids).
CXL 2.0 allowed a single layer of switching; CXL 3.0 adds multi-tiered switching, which enables switch fabrics (Rambus).
Sources
Primary is the original paper, standard or datasheet. Secondary is a review, a vendor summary or a news report. Measured is my own test data.
Show all 4 sources, 1 primary
- SecondaryCXL is finally coming in 2025ServeTheHome
- SecondaryCXL is Finally Coming in 2025 (ServeTheHome)ServeTheHome
- PrimaryCXL Consortium Releases the Compute Express Link 4.0 SpecificationCXL Consortium, 2025
- SecondaryCXL 3.0 Turns Up Scalability to 11Rambus, 2022