I mean, in reality TCP congestion control just isn't designed for today's Internet. We live in a world of huge bandwidth-delay products and short connections, t

I mean, in reality TCP congestion control just isn't designed for today's Internet. We live in a world of huge bandwidth-delay products and short connections, the opposite of what was the case when Van Jacobsen proposed it almost 30 years ago (to be fair, it's pretty damn impressive that his basic idea has prevented congestion collapse from recurring despite decades' worth of network evolution). Google's position on window size definitely makes sense in that regard but the very existence of "magic numbers" would suggest that there's room for some fundamental improvement. I think there are some really great ideas in the RCP project [1], which basically uses some information provided by routers to allow all flows to achieve their maximum steady-state fair-share allocation within one RTT. Even if it doesn't see the light of day on the broader Internet, I think it has excellent potential for datacenter networks. That's article you linked is a really great summary of this issue; thanks for sharing that with me. [1] http://yuba.stanford.edu/rcp/ http://yuba.stanford.edu/rcp/