MT7603E has high wifi latency

[danafortyfour]

When running flent rrul -p all_scaled -l 60 -H netperf.bufferbloat.net -o mt76.png Or equivalent to a local server wired into the lan the wifi performance is unusable. When on the 5GHz mt7612 radio on the same Netgear r6220 device the performance is much more consistent.

See last three images in https://forum.openwrt.org/t/how-to-write-a-meaningful-mt76-lag-bug/82515/19 for a sample.

[JFtico]

Try the 21.02 branch, it seems to have significant improvements in this area. I get both high-speeds (300Mbps) and low latency (A BufferBloat grade from DSLreports) on the 5Ghz radio. Speed is lower, but latencies are still OK on the 2.4 radio as well.

[danafortyfour]

I still have the same problem with the recently released 21.02. Maybe the bug needs to specify under load? Maybe it is related to my home environment with ~50 smart devices? I'm testing with an Intel 9560 in my laptop on today's latest drivers.

@JFtico are you able to try flent to reproduce? flent rrul -p all_scaled -l 60 -H netperf.bufferbloat.net -o mt76.png

I get these cut up results.

With 19.07 5GHz I was able to get a nice graph like this:

[trailblazergt]

I can still confirm the same issue on 2.4Ghz with Archer C50 V3 and OpenWrt version 22.03.0-rc1.