Re: pf and max bandwidth in nested queues (bug?)

Op 1-11-2017 om 14:22 schreef Oliver Humpage:
> Hello,
>
> I have an OpenBSD 6.2 router, set up in a test rig so there's no traffic apart from my tests. It has vmx interfaces. $int_if is a vlan on one of them.
>
> I have an issue where if a child queue has a different "max" from a parent queue, the bandwidth is throttled down to much less than either.
>
> I have the following simple queue tree (eventually it will be bigger, this is just for testing):
>
> queue inbound on $int_if bandwidth 100M
> queue inbound_all parent inbound bandwidth 30M max 30M
> queue inbound_std parent inbound_all bandwidth 20M max 30M default
> pass on $int_if
>
> This works, and an iperf test shunting data through the router from ext->int gets around 30Mb as expected.
>
> If I change the inbound_all queue's max to a slightly higher number, this shouldn't have any effect at all - after all, the inbound_std queue is still "bandwidth 20M max 30M", and neither of these numbers exceed the parent:
>
> queue inbound on $int_if bandwidth 100M
> queue inbound_all parent inbound bandwidth 30M max 40M
> ^^^^^^^
> queue inbound_std parent inbound_all bandwidth 20M max 30M default
> pass on $int_if
>
> However, when I do this, suddenly connections assigned to inbound_std only get around 2.3Mb.
>
> ``systat q'' shows all packets are going into the correct queue.
>
> As an experiment, I put a "min" level on inbound_std:
>
> queue inbound_std parent inbound_all bandwidth 20M min 10M max 30M default
>
> Then connections get that minimum bandwidth (here, iperf reported around 10Mb), so it shows the queue *can* use more than 2.3Mb, but it still sticks to the min rather than using all available bandwidth.
>
> This seems like a bug to me, although I'm hesitant to suggest it since I have a lot of respect for the OpenBSD team. Does anyone have a suggestion as to what's happening?
>
> Thanks,
>
> Oliver.
>

I might be mistaken, but doesn't queueing only work on OUTgoing traffic
since one cannot control the rate at which traffic is delivered to you,
but one can control the rate of traffic going out of an interface?

Erik