Sqm overhead and mpu for fiber with pppoe and vlan

guys im new on openwrt and im optimizing my internet for gaming i have fiber internet with pppoe and vlan that i need to set them and my router flint 2 router and my speed is 500 download and 200 upload what overhead and mpu in sqm i should use ?

i have seen the the openwrt sqm wiki but they didnt mention the fiber with pppoe and vlan

when i use 44 overhead and 84 mpu i need to lower my download to 100 from 500 to get around 3 download bufferbload but my upload i lower it to 190 and i get 0 upload bufferbloat

and for mtu what i put in for eth1 and (eth1.10 this one for my vlan) and pppoe-wan interfaces

PPP 2 bytes
PPPoE 6 bytes
Ethernet II 14 bytes
Ethernet FCS 4 bytes

26 bytes total then add 4 bytes for VLAN tag then it is 30 bytes. Or if double tagged 34 bytes.

However, I have read that 44 bytes is a conservative value and it is what it is selected by OpenWRT via Luci when you select Ethernet + overhead in the link layer adaptation tab.

So if you have 44 bytes that is acceptable. But maybe try with 30 bytes and compare.

  • For the pppoe interface set MTU to 1492 unless your ISP uses 1500. Rest leave as 1500.
  • MPU: 64 (start with 64; if you see issues with small-packet latency, try 84 as you have).

You select the pppoe-wan interface for the SQM device.

Also I assume you did this but

SQM link rates

Set download to ~95% of measured (500 Mbps -> 475 Mbps).
Set upload to ~95% of measured (200 Mbps -> 190 Mbps).