SQM QoS for bufferbloat really limits downstream bandwidth

So, if you have time and dedication to invest in debugging this, I would like you to post the following information:

  1. disable sqm and run a dslreports speedtest (see https://forum.openwrt.org/t/sqm-qos-recommended-settings-for-the-dslreports-speedtest-bufferbloat-testing/2803 for recommendations how to configure that test and how to link in the results)

  2. enable sqm (with download set to 0 and upload set to 12720) and post the output of:

a) cat /etc/config/sqm
b) tc -s qdisc
c) SQM_DEBUG=1 SQM_VERBOSITY_MAX=8 /etc/init.d/sqm stop ; SQM_DEBUG=1 SQM_VERBOSITY_MAX=8 /etc/init.d/sqm start

  1. run a deslreports speedtest and post the result and post the output of:
    a) tc -s qdisc

This is first to try to understand the situation with the download shaper set to 0, we might need to repeat the same thing for a realistic upload shaper value later.

I agree with @el-guapin that knowing whether you tested over wifi or wired is interesting, and for this set of tests I would like to ask you to test over a wire connection.

Since this seems to be a cable link I would also like to see the output from the "Share Your Results" box of https://www.speedguide.net/analyzer.php to rule out ds-lite and also the output of
ifstatus wan
since this is a bit verbose please only copy the following three fields (your values will be different, I just left mine in for reference)
"l3_device": "pppoe-wan",
"proto": "pppoe",
"device": "eth1.7",

Good luck!

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