I attended several sessions at last week's Hot Chips, and NVIDIA's NVSwitch talk was a standout. Ashraf Eassa did a great job of covering the talk's contents in an NVIDIA blog, so I will focus on analysis here.  SuperPOD Bids Adieu to InfiniBand From a system-architecture perspective, the biggest change is extending NVLink beyond a single chassis. NVLink Network is a new protocol built on the NVLink4 link layer. It reuses 400G Ethernet cabling to enable passive-copper (DAC), active-copper (AEC), and optical links. The build its DGX H100 SuperPOD, NVIDIA designed a 1U switch system around a pair of NVSwitch chips. The pod ("scalable unit") includes a central rack with 18 NVLink Switch systems, connecting 32 DGX H100 nodes in a two-level fat-tree topology. This pod interconnect yields 460.8Tbps of bisectional bandwidth. NVLink Network replaces InfiniBand (IB) as the first level of interconnect in DGX SuperPODs. The A100 generation pod uses an IB HDR leaf/spine inte...

Just a quick note to say I'll be attending (virtually) Hot Chips  on August 21-23 and plan to be on-site for the OCP Global Summit on October 18-20. Please reach out to schedule meetings and briefings either in advance or at these events.