Thanks for the nudge... I just tested this on the original one-armed router setup I encountered it on (3.16.7, routing from eth0 to eth0.3300). The patch makes a big improvement over the original (which was around 10/80):

IP 1, 1 up: 47.0 Mbit
IP 2, 8 up: 47.0 Mbit
IP 1, 8 down: 46.7 Mbit
IP 2, 1 down: 46.6 Mbit

Curiously, if my one-armed router has cake applied on egress and ingress of eth0.3300, instead of egress of eth0 and egress of eth0.3300 as above, some reduction in fairness occurs, but only for the downstream flows. This increases with the number of flows:

IP 1, 1 up: 47.2 Mbit
IP 2, 8 up: 47.2 Mbit
IP 1, 8 down: 44.5 Mbit
IP 2, 1 down: 48.7 Mbit

IP 1, 1 up: 47.0 Mbit
IP 2, 16 up: 47.0 Mbit
IP 1, 16 down: 42.6 Mbit
IP 2, 1 down: 50.3 Mbit

IP 1, 1 up: 47.2 Mbit
IP 2, 32 up: 47.0 Mbit
IP 1, 32 down: 41.4 Mbit
IP 2, 1 down: 51.3 Mbit

It still happens when ether-vlan is used on the leaf qdiscs with vlan traffic.

That said, unless there’s an obvious reason for this that’s fixable, I’m fine with how it is, considering the improvement. :)

> On Feb 28, 2019, at 12:17 PM, Toke Høiland-Jørgensen via Cake <cake@lists.bufferbloat.net> wrote:
> 
> 
> From: Toke Høiland-Jørgensen <toke@toke.dk>
> Subject: Upstream submission of dual-mode fairness patch
> Date: February 28, 2019 at 12:17:39 PM GMT+1
> To: cake@lists.bufferbloat.net
> 
> 
> Hey everyone
> 
> The dual-mode fairness patch has been in the github repo for a few weeks
> now, and no one has complained. If no one continues to complain, I'll
> submit it upstream tomorrow along with Kevin's fwmark patch.
> 
> So if anyone else wants to test, now would be a good time to do so :)
> 
> -Toke
> 
> 
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