[Cake] Long-RTT broken again

[Toke Høiland-Jørgensen]

Jonathan Morton <chromatix99 at gmail.com> writes:

> So, again - what’s going on?  Are there any clues in packet traces
> with sequence analysis?

So, reran and took traces. Data and packet dumps at:
https://kau.toke.dk/experiments/cake/longrtt/

There's two runs: the first one is what's in git now, the second one
patches the byte accounting to use the packet length rather than the
truesize, which helps a bit but is still inadequate.

The packet dumps and cake stats output agree: cake is running out of
buffer size. ECN is enabled on this test, and there's not a single mark
performed, but several thousand drops.

So something is definitely wrong with the buffer sizing.

-Toke