While using today's master ( 10/09/2024 ) I noticed that if I have a slow device connected to a bridged port the download speed for all ports will be capped at the slow device speed.
Example:
br-lan is stock with lan1,lan2,lan3 and eth2 bridged.
connect two of the lan ports with gigabit lan card computers, for instance lan1 and lan2
connect the third lan port with a 10mbits/s lan card computer, for instance lan3
test speed between openwrt and the gigabit devices with iperf3. upload will be ok ( ~992mbits/sec ) downloads will be capped at around 10mbits/sec ( iperf3 -R to test the download )
disconnect the 10mbits/sec device, speeds will be ok of both upload and download.
this has happened to other users with different hardware: