[Cake] Upstream submission of dual-mode fairness patch

[Pete Heist]

> On Mar 3, 2019, at 1:13 PM, Jonathan Morton <chromatix99 at gmail.com> wrote:
> 
> So I'm not entirely sure what's happening here, but at least the asymmetry isn't too bad; it's achieving significantly better host-fairness than a pure flow-fair system would.

Yeah, it’s not a big problem, and IMO it’s in the preferable direction where the 1-flow IP “wins” over the N-flow IP. It’s just a matter of either flushing out or explaining the asymmetry, if possible.

Does it say anything to you that enabling ECN makes the asymmetry go away?