Default qdisc is not fq_codel on OpenWrt 22.03.3

I am confused with your comment. Should I select eth0 for SQM interface. I want to give about how I had configured SQM-cake with details.

I had set SQM interface to wan. I have 50Mbps/5Mbps cable (Docsis 3.0) plan and I get 48.8Mbps/4,85Mbps upload from iperf test without SQM.

SQM configuration is:

root@RB750Gr3:~# cat /etc/config/sqm 

config queue 'eth1'
    option qdisc 'cake'
    option script 'piece_of_cake.qos'
    option interface 'wan'
    option debug_logging '0'
    option verbosity '5'
    option qdisc_advanced '1'
    option ingress_ecn 'ECN'
    option egress_ecn 'NOECN'
    option linklayer 'ethernet'
    option overhead '22'
    option linklayer_advanced '1'
    option tcMTU '2047'
    option tcTSIZE '128'
    option tcMPU '64'
    option linklayer_adaptation_mechanism 'default'
    option qdisc_really_really_advanced '1'
    option iqdisc_opts 'nat dual-dsthost'
    option eqdisc_opts 'nat dual-srchost ack-filter'
    option upload '4320'
    option squash_dscp '0'
    option download '40000'
    option squash_ingress '1'
    option enabled '1'

Some times web page loading had stuck or waiting for a long time. After searching forum, I had found @moeller0's advice on this post. There was large packets on wan and ifb4wan interfaces ( max_len on Cake statistics) too. I had installed ethtool and run theese commands.

ethtool -K wan tso off gso off gro off
ethtool -K lan2 tso off gso off gro off
ethtool -K lan3 tso off gso off gro off
ethtool -K lan4 tso off gso off gro off
ethtool -K lan5 tso off gso off gro off

After some iperf test which run for upload and download same time, I got these results.

root@RB750Gr3:~# tc -s qdisc show dev wan
qdisc cake 8005: root refcnt 2 bandwidth 4320Kbit besteffort dual-srchost nat nowash ack-filter split-gso rtt 100ms noatm overhead 22 mpu 64 
 Sent 118261315 bytes 898179 pkt (dropped 96706, overlimits 572255 requeues 0) 
 backlog 0b 0p requeues 0
 memory used: 251424b of 4Mb
 capacity estimate: 4320Kbit
 min/max network layer size:           28 /    1500
 min/max overhead-adjusted size:       64 /    1522
 average network hdr offset:           14

                  Tin 0
  thresh       4320Kbit
  target            5ms
  interval        100ms
  pk_delay       1.19ms
  av_delay        188us
  sp_delay         18us
  backlog            0b
  pkts           994885
  bytes       126404190
  way_inds         3495
  way_miss        13225
  way_cols            0
  drops             259
  marks               0
  ack_drop        96447
  sp_flows            1
  bk_flows            1
  un_flows            0
  max_len          1514
  quantum           300

qdisc ingress ffff: parent ffff:fff1 ---------------- 
 Sent 1778232547 bytes 1378731 pkt (dropped 0, overlimits 0 requeues 0) 
 backlog 0b 0p requeues 0

 root@RB750Gr3:~# tc -s qdisc show dev ifb4wan
qdisc cake 8006: root refcnt 2 bandwidth 40Mbit besteffort dual-dsthost nat nowash no-ack-filter split-gso rtt 100ms noatm overhead 22 mpu 64 
 Sent 1786967097 bytes 1371699 pkt (dropped 7039, overlimits 1068899 requeues 0) 
 backlog 0b 0p requeues 0
 memory used: 1073088b of 4Mb
 capacity estimate: 40Mbit
 min/max network layer size:           46 /    1500
 min/max overhead-adjusted size:       68 /    1522
 average network hdr offset:           14

                  Tin 0
  thresh         40Mbit
  target            5ms
  interval        100ms
  pk_delay       6.61ms
  av_delay        4.1ms
  sp_delay         16us
  backlog            0b
  pkts          1378738
  bytes      1797535372
  way_inds        11860
  way_miss        11770
  way_cols            0
  drops            7039
  marks               5
  ack_drop            0
  sp_flows            2
  bk_flows            1
  un_flows            0
  max_len          1514
  quantum          1220

After activate SQM on wan :

root@RB750Gr3:~# tc qdisc show
qdisc noqueue 0: dev lo root refcnt 2 
qdisc fq_codel 0: dev eth0 root refcnt 2 limit 10240p flows 1024 quantum 1518 target 5ms interval 100ms memory_limit 4Mb ecn drop_batch 64 
qdisc cake 8005: dev wan root refcnt 2 bandwidth 4320Kbit besteffort dual-srchost nat nowash ack-filter split-gso rtt 100ms noatm overhead 22 mpu 64 
qdisc ingress ffff: dev wan parent ffff:fff1 ---------------- 
qdisc noqueue 0: dev lan2 root refcnt 2 
qdisc noqueue 0: dev lan3 root refcnt 2 
qdisc noqueue 0: dev lan4 root refcnt 2 
qdisc noqueue 0: dev lan5 root refcnt 2 
qdisc noqueue 0: dev br-lan root refcnt 2 
qdisc cake 8006: dev ifb4wan root refcnt 2 bandwidth 40Mbit besteffort dual-dsthost nat nowash no-ack-filter split-gso rtt 100ms noatm overhead 22 mpu 64

Is this configuration wright. Would you help me to make wright configuration of SQM.