Bad latency and jitter with SQM on ArcherC7v2

Installing and Using OpenWrt Network and Wireless Configuration
2

Try:

config queue 'sqmqueue1'
	option ingress_ecn 'ECN'
	option egress_ecn 'NOECN'
	option itarget 'auto'
	option etarget 'auto'
	option verbosity '5'
	option qdisc 'cake'
	option script 'layer_cake.qos'
	option qdisc_advanced '1'
	option squash_dscp '1'
	option squash_ingress '1'
	option qdisc_really_really_advanced '1'
	option eqdisc_opts 'nat dual-srchost ack-filter'
	option linklayer 'ethernet'
	option linklayer_advanced '1'
	option tcMTU '2047'
	option tcTSIZE '128'
	option linklayer_adaptation_mechanism 'default'
	option debug_logging '1'
	option enabled '1'
	option iqdisc_opts 'nat dual-dsthost ingress'
	option interface 'eth0'
	option download '16000'
	option upload '2000'
	option overhead '18'
	option tcMPU '64'

Also, the tc output does not indicate long delays inside cake...

Could you also post the type of your docsis-modem and the output of ifstatus wan please to confirm that eth0 is the correct wan interface.