Alibaba's Panjiu 128 is not a true rack scale up. Panjiu 128 is made up of two 64 scale up size systems with ALink switch cartridges in the back. Alibaba's own architecture write-up says a single 128 domain would need 128-port switch chips, and the ICN Switch 1.0 is a 25.6 Tbps part sized for 64. We covered this during our Alibaba Apsara Conference takeaways note where we found that only Panjiu 144, with switches in the middle of the rack, is a true rack-scale domain which is not due until 2028. (1/2)🧵