Linksys WRT1900AC V1 (throughput) is broken after DSA migration (OpenWrt 21/22/23)

The Linksys WRT1900AC&throughput is very poor after upgraded to OpenWrt 21, 22 and 23 where DSA replaced swconfig. With OpenWrt 19, the Linksys WRT1900AC V1 can handle Gigabit (940Mbps) WAN to LAN throughput. However, it only does 350/800 Mbps with OpenWrt 21/22/23 (PPPoE). WAN to LAN throughput better for DHCP (780/660 Mbps), but still far away from the expected throughput. For now, the only solution I have to improve the performance is downgrading the WRT1900AC to OpenWrt 19 where swconfig is being used. If you have any idea how to get a better throughput/performance with OpenWrt 21/22/23, please share in the comment section. Video timeframe: 00:00 - Intro & Story 01:15 - WRT1900AC V1 Throughput with OpenWrt 22 (DSA) 02:32 - Failed to Downgrade from OpenWrt 22 to OpenWrt 19 using LuCI 03:16 - Revert / Return Linksys WRT1900AC V1 to stock firmware 03:51 - Install OpenWrt 19 from Linksys Stock Firmware 04:20 - Configure PPPoE with VLAN tagging 04:54 - PPPoE throughput - SW Offloading Disabled 05:12 - PPPoE throughput - SW Offloading Enabled 05:46 - Configure PPPoE with no VLAN tagging & throughput 06:23 - Final words That is all. Thanks for watching and see you in the next video!