Current public SOTA seems to be “no congestion control”

> We proceeded without DCQCN for our 400G deployments. At this time, we have had over a year of experience with just PFC for flow control, without any other transport-level congestion control. We have observed stable performance and lack of persistent congestion for training collectives.

https://engineering.fb.com/2024/08/05/data-center-engineerin...