Nope. It's all 100GbE throughout as far as I know. And people do work really hard to be able to saturate that bandwidth as it is by no means a trivial task to saturate it through the usual, naive means without the use of RDMA and Verbs. Years ago when I was there it was (IIRC) 40Gbps to each node straight up.

It's a necessity really. All storage at Google has been remote and distributed for at least the past decade. That puts serious demands on network throughput if you want your CPUs to actually do work and not just sit there and wait for data.

Here's some detail as of 2012: https://storage.googleapis.com/pub-tools-public-publication-.... Note that host speed is 40Gbps. And here's FB talking about migrating from 40Gbps to 100Gbps in 2016: https://code.fb.com/data-center-engineering/introducing-back...