QOS features cutting speeds and making no difference in bufferbloat?

[Yowie]

I have XFINITY gigabit, ASUS RT-BE86U, Merlin firmware, hard wired to PC, Download speeds are 1200mbps and 40mbps upload.

Whenever I pick a QOS option, they all halve my internet speeds to around 500mbps download on speed tests? I've even tried Cake with default and cable docsis selected and the bufferbloat tests don't even improve, I get a C rating from https://www.waveform.com/tools/bufferbloat with the settings in the image. I see the download speed peak at 1200mbps for 1-2 seconds, then it immediately drops to 500mbps, but I still get a C rating with ping spiking to 500ms, like the QOS is delayed in kicking in.

I tried a basic bandwidth limiter across the entire DHCP ip range, same issue.

Is it because QOS disables hardware NAT and I'm forced to 500mbps max? Can I fix bufferbloat without 50% cost of my speed?

 

[dave14305]

You’re screwed. Only Adaptive QoS keeps HW acceleration enabled, but Adaptive QoS is believed to be broken by Asus on BE routers.

 

[Yowie]

You’re screwed. Only Adaptive QoS keeps HW acceleration enabled, but Adaptive QoS is believed to be broken by Asus on BE routers.

Which routers does it work on? I can still return this router. Does it work properly on RT-AX86U?

 

[dave14305]

Which routers does it work on? I can still return this router. Does it work properly on RT-AX86U?

If you want reliable QoS/SQM for gigabit, you should instead look for an x86-based machine to be the router (e.g. running OpenWrt with SQM), and use a wireless router as an access point only.

Asus lost their way with QoS some time ago. You really only need QoS for your asymmetric upload speed.