On Mon, Feb 22, 2021 at 08:51:32PM -0500, Steven Shockley wrote: > I have OpenBSD 6.8 running on a Dell R210-II acting as a firewall/router. > To combat bufferbloat I tried implementing FQ-CoDel queueing. The WAN > bandwidth is advertised as 940 Mbit/sec down and 840 Mbit/sec up. > > I've tried adding one or the other of these lines to my pf.conf: > > queue outq on $ext_if flows 1024 bandwidth 1024M max 1024M qlimit 1024 > default > or > queue outq on $ext_if flows 1024 qlimit 1024 default > > In both cases, upload speeds drop from ~800 Mbit/sec to < 100 Mbit/sec. > Changing the 1024M to other values makes little or no difference. To be > fair, bufferbloat does improve, but that's quite a hit. I'm measuring using > the dslreports.com speed test via wired ethernet through a Cisco 3750x. > > One possible complexity is that the internal interface is tagged VLANs, but > if it were an MTU issue I'd expect it to affect performance across the > board. > > Any suggestions? I'm happy to post dmesg/pf.conf/diagrams if they'd help. > Thanks.
I've noticed a similar effect on a slower link (VDSL with 50 down/ 10 up). In this case the VDSL modem presents an Ethernet switch, so there is no pppoe or vlan involved in the box that runs pf. As soon as I enable this example given in pf.conf(5): queue outq on em0 bandwidth 9M max 9M flows 1024 qlimit 1024 \ default I see only about 2 or 3 Mbit/s max upload during tcpbench. Which is indeed quite a hit compared to 10M. Without the queue tcpbench goes up to 9 Mbit/s. It varies a lot between 5 and 9, which I thought might be a reason for my issue with queueing enabled. Currently, I am simply running this setup without any queueing.