pfSense

There's something very odd going on with this. I can reproduce the problem, but only if I set the pipe bandwidth sufficiently high.

At 10Mbps the traffic (mostly) matches the configured weights. At 100Mbps it does not, there it's closer to 60/40 Mbit/s.
At 10Mbps with 5 and 100 weights I see mostly ~460Kbit/s and 9.2Mbit/s, with regular (once every 10 seconds or so) excursions to 9Mbit/s and 2Mbit/s (so almost the inverse of what's expected).

Taken together I suspect there's a scaling or number overflow issue in the scheduling code.

Does it help to increase the queue length there? Normally we recommend setting it to >= 1000 for 100Mbit/s and even higher for faster links.

The bandwidth limits I have are 140 up 9 down and the issue persists there even with a queue length of 1400/90.

Increasing the queue lengths of the individual queues appears to help. I tested with a queue of 5000 at 100Mbps. Increasing the queue length on the scheduler itself does not affect things, but is required for the GUI to set net.inet.ip.dummynet.pipe_slot_limit.

That is, I think there's a minor issue in the GUI, because it's possible to set a queue size of 5000 on the (child) queue without setting that on the scheduler, and then the dummynet configuration will fail to load, without visible indication of this on the GUI. WF2Q itself appears to work as expected.

Setting the queue length on the child queue AND parent scheduler worked! (also have to keep this bug in mind #13158)