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.
