I've tried many different settings for SQM to get rid of bufferbloat.
Device: Xiaomi mi a4 gigabit using OpenWRT 21.02.3(Released couple days ago)
Wireguard always on (wireguard client).
MTU is left as wireguard's default 1420 on Wireguard interface.
ISP DL speed 50 mbps - Upload 5 mbps
I guess I have some kind of fiber connection(?), got a very small ONT device connected to my router. It's PPPOE.
Normally I have 100 ms latency to the wireguard server. 130-150 ms to websites.
My latency skyrockets +500 +1-2k under load.
Things I tried for SQM Setup
Download speed (kbit/s) (ingress): 40k, 42,5k
Upload speed (kbit/s) (egress): 4k, 4,25k
piece of cake
Link Layer Adaptation: None
Link Layer Adaptation: Ethernet with overhead
Per Packet Overhead: 44, 84, 104, 124 (also some other values)
Advanced strings (for both ingress and egress): nat, ack-filter, oceanic, satellite, mpu 64, mpu 84
Nothing I did yielded me any better results than keeping SQM off. What gives!?
a full sized packet around 1500+ (here 1538 for ethernet) bytes will take: 1000*(1538*8)/(5*1000^2) = 2.46 ms when being received 1000*(1538*8)/(0.5*1000^2) = 24.6 ms when being sent.
this is not completely terrible, but that is low enough that you need to manage your expectations, sorry.
So the standard approach would be to try figuring out:
a) what exactly you tried to configure (when using cake the easiest is to run tc -s qdisc and copy and paste the output)
b) what did you do to assess latency under load and from what host (e.g. wired computer, or wireless device connected via WiFi)
these will configure a larger target and interval which wil result in more latency under load.... you really only need those if your experenced RTTs are significantly above the 100ms that cake/fq_codel default to. Increasing this will at best give you a bit more throughput, but certainly increase the "residual bufferbloat".
Yes of course. I only use it to prevent my ISP throttling me. It seems I should really be using a VPS (although I don't understand if that would give the same performance vs NordVPN). I see no appreciable latency/bandwidth difference between not using VPN and using VPN (setting aside the ISP throttling on ports 80 and 443). But then my LTE connection is circa 45ms RTT to first hop and bandwidth between 10Mbit/s and 70Mbit/s.
Is your bandwidth even through VPN and ping to say 18.104.22.168 stable?