PPPoE and high usage CPU with HW NAT on MT7621A

I have a problem with the high usage of CPU when I'm using PPPoE.
I'm using OpenWRT 20.3.2 on the router.
Also on iperf3 I can't achieve 1Gbit/s the score is around 500-600 Mbit/s on one connection.
I think the HW NAT is not working, and I don't know why it is not working with PPPoE?
CPU usage when I'm running Speed Test. I have 600 Mbit/s PPPoE from ISP and on ZBT WG-3526 1 Gbit/s connection speed is around 400-550 Mbit/s with high CPU usage.


RC2 is out

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That seems to be very reasonable numbers, you can't offload all processing of network traffic and from what I recall 500mbit seems about what one core can handle which is pretty impressive given the overall performance of a very old 1004Kc MIPS core :wink:

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22.03 rc1 does not have this commit:
kernel: fix flow offload issues with pppoe
So you may want to try either a current snapshot, or 22.03 rc2 and see if it improves things.

If you are not using it already, you might also give irqbalance a try.

My ISP connection was not PPPoE, but when I used an ER-X (also MT7621) as my gateway router, a Speedtest Download could max out my ~450 Mbps ISP service with essentially no CPU usage if hardware NAT was enabled using a then current (~ 6 months ago) snapshot.

MT7621 can handle a Gigabit connection with its hardware NAT, but that is all it can handle - no SQM or any other services that needs to put everything through the CPU. And I do recall reading PPPoE slows things down, but I can't tell you how much - I've no experience with that.

I downgraded the router to 19.07.10 the main MT7621A router with PPPoE mwan3 interface as the main connection, and 4G LTE Failover with MiniPCI-E card.
NAT on the second router works fine on 21.02.3 with an ethernet connection that is bridged. I will try to upgrade to the newest branch.
Now I see a problem with higher CPU usage when I'm running iperf3 over a 5G WiFi network, and Speed Test.
Is MT7623 support HW NAT?
I'm searching powerful OpenWRT router with a MiniPCI-E slot for LTE Quectel EP-06 failover connection?

Pcengine APUx boards or anything based on the same hardware (cpu AMD GX-412TC)

did something happen to rc2? the link dosent work

looks like they removed it, like RC3 btw

so i need to wait for 22.x.x stable release if im using pppoe and want to reach my full internet speed?

You can use snapshot from here:

can i just upgrade from stable to snapshot without reinstalling luci?

All your custom packages are needed to be reinstalled manually, Luci in a snapshot is absent. You can install it manually.

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yes you can, if you create a custom snapshot image by adding luci in the snapshot from here :

can i upgrade from stable using luci with the sysupgrade file i made with luci?