Possible to apply QoS only to upload?

[MariaPhilips]

I have an RT-AX58U running the latest stable version of Asuswrt-Merlin. My connection is 1000M download, 50M upload.

With no QoS my real speeds are about 920M download, 39M upload. I'm happy with the download, but the upload is suffering because I'm constantly hitting my ISP's policer. So I want to shape the upload so I can get closer to the 50M I'm paying for.

Seems I can only apply QoS to both download and upload at the same time though. My upload speeds are improved to close to 50M, but my download speeds are reduced significantly to about 350M because QoS disables hardware acceleration.

So does anyone know if it's possible to apply QoS/queueing only to the upload? If so, how?
Many Thanks!

 

[ColinTaylor]

... but my download speeds are reduced significantly to about 350M because QoS disables hardware acceleration.

I didn't think that was the case on that model. Are you using Adaptive QoS?

 

[MariaPhilips]

I was using QoS Type "Traditional QoS". This results in 350 Mbps download speeds and "HW acceleration: Runner: Disabled (QoS) - Flow Cache: Disabled (QoS)". Same goes for QoS Type "Bandwidth Limiter".

Changing to QoS Type "Adaptive QoS" results in 700 Mbps download speeds and "HW acceleration: Runner: Disabled (QoS) - Flow Cache: Enabled". Better, but still not great.

QoS disabled gives me 930 Mbps download speeds and "HW acceleration: Runner: Enabled - Flow Cache: Enabled".

Ideally I'd like to have QoS enabled only for outbound traffic but not affect inbound traffic at all. Is that impossible?

 

[ColinTaylor]

Is that impossible?

Yes. You cannot enable QoS in only one direction.

Maybe you can use FlexQoS to improve the throughput.

 

[MariaPhilips]

Thanks for confirming.

That's disappointing. I had hoped it may be possible, as it was on my previous Mikrotik and OpenWRT routers.

 

[ColinTaylor]

See my edit above regarding FlexQoS. I don't know whether it will help (perhaps by removing all the download QoS rules) as I've never used it myself.

 

[dave14305]

The AX58U has some issues in the ASUS code used in 384.19 that isn't limiting upload, IIRC. FlexQoS can't do anything to overcome this since it relies on the same underlying mechanisms as Adaptive QoS.

So unfortunately, Colin won't collect his referral fee this time.

I've been spending a lot of time on the OpenWRT forums lately, and the consensus is that if you want to do traffic shaping with gigabit connections, you really need x86-based hardware, or even a Raspberry Pi 4 running OpenWRT can handle this kind of bandwidth. I'm going to try this over the Christmas holiday while the kids are out of school, even though I don't have Gigabit speeds.

 

[MariaPhilips]

the consensus is that if you want to do traffic shaping with gigabit connections, you really need x86-based hardware, or even a Raspberry Pi 4 running OpenWRT can handle this kind of bandwidth.

I'd tend to agree. However I'm only trying to shape 50 Mbps egress. The 1 Gbps ingress shouldn't be touched at all. Guess it's impossible on Asus.

 

[MariaPhilips]

Here's an update. It was actually incredibly easy to do from the command line. QoS is turned off in the Asuswrt-Merlin GUI.

tc qdisc replace dev eth4 root handle 1: htb default 1
tc class add dev eth4 parent 1: classid 1:1 htb rate 50mbit quantum 1514

End result: 939 Mbps download, 48 Mbps upload

 

[dave14305]

Isn’t the issue though that with hardware acceleration enabled (to get your full bandwidth), not all your packets will be visible to the kernel for shaping?

 

[MariaPhilips]

Can't say for sure as I don't know the ins and outs of tc. It definitely works though.

Speedtest: https://www.speedtest.net/my-result/d/c72f1859-e07f-4316-a8b3-9c9ac51d9127

 

[MariaPhilips]

Okay, I just noticed that CPU1 hits 100% when downloading, so I guess hardware acceleration is indeed disabled with the above commands.

Maybe the RT-AX58U's CPU is just powerful enough to hit 930 Mbps with a simple two-line tc configuration.