[Bloat] cake + ipv6

[Jonathan Morton]

> On 23 Sep, 2020, at 8:36 pm, Daniel Sterling <sterling.daniel at gmail.com> wrote:
> 
> I ran some updates on the xbox and watched iftop. I found that the
> xbox does the following:
> 
> * uses up to four http (TCP port 80) connections at once to download data
> * connects (seemingly randomly) to both ipv4 and ipv6 update hosts
> 
> That means at any given time, the xbox could be downloading solely via
> ipv4, solely via ipv6, or a with mix of the two.
> 
> I believe this means when it's using both v4 and v6, it's getting
> double its "share" of the bandwidth since cake can't tell that the v4
> and v6 traffic is coming from the same LAN host -- is that correct?

It fits my mental model, yes, though obviously the ideal would be to recognise that the xbox is a singular machine.  Are you seeing a larger disparity than that?  If so, is it even larger than four connections would justify without host-fairness?

> I'm using the default "triple-isolate" parameter. I can try switching
> to dual-src/dest host or even plain srchost / dsthost isolation. In
> theory that should limit traffic more per download host, even if cake
> can't determine the LAN host that's doing the downloading, right?

Triple-isolate is designed to function reasonably well when the user can't be sure which side of the network is the LAN!  The "dual" modes provide Cake with that information explicitly, so may be more reliable in corner cases.

For your topology, eth0 (LAN egress) should get dual-dsthost, and eth1 (WAN egress) should get dual-srchost.

 - Jonathan Morton