[HN Gopher] Next-Gen Broadcom PCIe Switches to Support AMD Infin...
       ___________________________________________________________________
        
       Next-Gen Broadcom PCIe Switches to Support AMD Infinity Fabric XGMI
        
       Author : jauntywundrkind
       Score  : 4 points
       Date   : 2023-12-11 22:02 UTC (59 minutes ago)
        
 (HTM) web link (www.servethehome.com)
 (TXT) w3m dump (www.servethehome.com)
        
       | jauntywundrkind wrote:
       | Super interesting possibilities here.
       | 
       | I'm curious how much of a role Infinity Fabric has to play
       | though, as it seems like CXL has a number of the same upsides.
       | For example:
       | 
       | > _We also heard another nugget at the show. Imagine not just the
       | CPU and GPU communication happening over XGMI / Infinity Fabric.
       | Instead, imagine a world with XGMI-connected NICs where the NIC
       | was on the same coherent fabric. If AMD intends to extend its AI
       | training clusters via Ultra Ethernet, then instead of having to
       | go CPU/ GPU to PCIe with RDMA transfers over the PCIe Ethernet
       | NIC, imagine having the XGMI NIC sitting on the Broadcom XGMI
       | switch with the CPU and multiple GPUs. That is a fascinating
       | concept._
       | 
       | CXL 3.1 was released two weeks ago, and it has support for p2p
       | DMA, where one device transfers directly to another device. That
       | would enable that same host-less transfer from NIC to GPU as
       | hypothesized here. https://news.ycombinator.com/item?id=38497690
       | https://www.servethehome.com/cxl-3-1-specification-aims-for-...
       | 
       | CXL 3.1 also specified host-to-host connections. I don't know if
       | it has anywhere near the coherency semantics Infinity Fabric has,
       | but this is another example of the open standard having lots of
       | overlapping capabilities with Infinity Fabric, and shows a
       | general convergence in capabilities of these fabrics.
        
       ___________________________________________________________________
       (page generated 2023-12-11 23:01 UTC)