Infinity Fabric

Infinity Fabric is a high-performance interconnected system of communication paths that uses sensors embedded in each die to route the signals around to the major components of an integrated circuit (IC) to scale control and data transmission across all linked components from die to socket to board-level.

Infinity Fabric can be used across various processors as an interconnection for communication between Graphics Processing Units (GPUs) and Central Processing Units (CPUs) while scaling up cores in a CPU or a GPU and maintaining cache coherency across multiple external processors (limited by the bandwidth of the transport). It allows processor designs to be scaled up or down within a matter of hours in a cost-effective way.  Infinity Fabric is a superset of HyperTransport; a socket-to-socket interconnected architecture that is used by various ICs to connect and interact with each other, as a point-to-point connection. Infinity Fabric is implemented at the transistor level physical hardware in AMD’s Zen CPUs and Vega GPUs.

SDF and SCF

Infinity Scalable Data Fabric (SDF) and Infinity Scalable Control Fabric (SCF) are the two main components of Infinity Fabric. SDF enables coherent communications among caches and between caches and memory, both from and to the cores, various local and non-local memory access in multiprocessing, and the other peripherals circuits. SDF enables scalability in terms of cores, CPUs, dies or sockets, among others. On the other hand, SCF connects computer elements. Each SCF has a dedicated IC for high-speed communication between serial and parallel interfaces that allows the SCFs of multiple chips within a system to talk to each other. The SCF also extends to the dies on a second socket in multi-way multiprocessing configurations. It handles the transmission of various system control signals used for thermal and power management, tests, security, and other third-party circuitry.