Ethernet Port performance M401A/RK3399(rtl)

[alcatraz-zz]

I'd like to report an unusual issue that's happened twice on armbian. I'm pretty sure they're on 6.12 and 6.1 kernels. I tried other kernels too and while the results change a little the problem remains.

I use these boxes to run xray servers. The box's ethernet connection throughput is normal for all other use cases (LAN services) but when running xray (high latency) there's a problem. The problem is that on a 100Mbit connection I get maybe 5-15Mbit throughput. The same happened on an RK3399 board running armbian with an rtl8211e nic.

Here's the odd thing. On the M401A, WHEN I connect a secondary nic like an rtl8152b usb nic, I get the full 100Mbit throughput on xray.

Although I haven't tested that on the RK3399, I think the same will happen. The primary nic is throttled to 5-15Mbit under high latency operation, the secondary nic is fine.

It's got nothing to do with the ISP as it works fine on non armbian platforms. (debian VM amd64)

I have the same settings on the debian vm as the armbian boxes. "fq" and "bbr", increased buffers sizes etc.

Any ideas? Thanks!

[alcatraz-zz]

@ophub Excuse my asking, but has anything in the firmware been changed in regards to this issue?

[ophub]

unifreq/linux-6.12.y@efcda2e
According to the update records of the upstream kernel repository, this patch recovers the previously lost 30% performance. You need to upgrade to version 6.12.21. The fix has also been applied in version 6.6.85. Try updating to the latest kernel.

[alcatraz-zz]

unifreq/linux-6.12.y@efcda2e According to the update records of the upstream kernel repository, this patch recovers the previously lost 30% performance. You need to upgrade to version 6.12.21. The fix has also been applied in version 6.6.85. Try updating to the latest kernel.

I'll try it. The performance loss I saw though was closer to 85%. Isn't it odd that a second usb nic doesn't have the issue?

I remember checking htop and the cores were not loaded at all when only seing 15% throughput (below 10% cpu). With the second nic fully loaded 100Mbit the cores got up to maybe 30-40% usage.