NVIDIA GB200 Interconnect Architecture Analysis-NVLink, InfiniBand, and Future Trends
NVIDIA GB200 Interconnect Architecture Analysis-NVLink, InfiniBand, and Future Trends 1. NVLink Bandwidth Calculation There is a lot of confusion in NVIDIA's calculation of NVLink transmission bandwidth and the concept of SubLink/Port/Lane. Typically, the NVLink 5 bandwidth of a single GB200 is 1.8TB/s, which is calculated by bandwidth-oriented individuals in bytes per second (Byte/s). However, on NVLink Switches or IB/Ethernet switches and network cards, Mellanox's perspective calculates it in terms of network bandwidth, usually in bits per second (bit/s), based on the transmitted data bits. Here, we'll explain in detail the calculation method of NVLink. Starting from NVLink 3.0, it is composed of four differential pairs to form a "sub-link" (often referred to by NVIDIA as Port/Link, with some ambiguity in definition). These 4 pairs of differential signal lines simultaneously contain both the receiving and transmitting directions of signal lines. Typically,...