Ran a series of dslreports with different configs and found minimal result differences between them.
Testing was done when network was not being loaded, so not real ideal test of QoS.
Bottom line not convinced any of below is statistically significant, nor am confident in dslreports testing effectiveness, nor in it being valid on less than highly loaded network.
But. For what its worth, here it is.
Am going to run the last config listed for a while and see how it goes.
I do tend to seem to have latency creep up over time and really slow responses when I know there's video streaming and other things going on, will be good to see what the results are with different loading.
Router: AC-3200
Figures below average of 3 or more runs
QoS settings tested:
157/11 bandwidth (connection is generally 180/12)
A few QoS rules I had in place prioritizing by client MAC address - but near zero network load while testing so doesn't reflect a real QoS active prioritization
Note all results run happily higher than the entered bandwidth which is odd - in previous routers with DD-WRT and QoS on, I would easily and reliably see the 'hard cap' of the QoS setting.
The Asus implementation seems to let traffic exceed the settings as long as there is no bottleneck?
Base case QoS off - default txqueue = 1000
180/12 - provider hard caps the up much more consistently than the down which seems to be able to burst, has always been this way - never see an upload test that isn't 12M
70-100ms for dslreports top list
dslreport scores B/A/A
Q0S off - txqueue = 100
178/12 perhaps tiny decline in download speed but not substantial
50-70 latencies - marginally better
Dslreports B/A+/A (up on 'quality')
Q0S on - sfq w/ default txqueue = 1000
178/12 roughly same as above
50-60 latencies - marginally better
Dslreports B/A+/A (same as above)
Q0S on - fq_codel w/ default txqueue = 1000
176/12 little slower still
45-60 latencies - marginally better
Dslreports B/A+/A (same as above)
Q0S on - fq_codel w/ txqueue = 8/40/40
179/12 faster than default txq
60-80 latencies - back down again
Dslreports B/A+/A (same as above)
Q0S on - fq_codel w/ txqueue = 100
180/11 faster than default txq
75-100 latencies - slower again
Dslreports B/A+/A (same as above)