US Patent 9639490 Ring protocol for low latency interconnect switch

Methods, systems, and apparatus for implementing low latency interconnect switches between CPU's and associated protocols. CPU's are configured to be installed on a main board including multiple CPU sockets linked in communication via CPU socket-to-socket interconnect links forming a CPU socket-to-socket ring interconnect. The CPU's are also configured to transfer data between one another by sending data via the CPU socket-to-socket interconnects. Data may be transferred using a packetized protocol, such as QPI, and the CPU's may also be configured to support coherent memory transactions across CPU's.