Have tested with iperf, after ~30min it stops:
./iperf3 -c 192.168.1.1 -t 86400
[ 4] 1683.00-1684.00 sec 2.44 KBytes 20.0 Kbits/sec
[ 4] 1684.00-1685.00 sec 6.96 KBytes 57.0 Kbits/sec
[ 4] 1685.00-1686.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1686.00-1687.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1687.00-1688.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1688.00-1689.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1689.00-1690.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1690.00-1691.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1691.00-1692.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1692.00-1693.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1693.00-1694.00 sec 0.00 Bytes 0.00 bits/sec
[ 4] 1694.00-1695.00 sec 0.00 Bytes 0.00 bits/sec
Neither KRACK or Low ACK works for me as well, have both enable on 2.4 (20MHz) and 5G (80MHz).
I didn't any firmware mod/replace, as I find it doesn't work as well, see posts below:
https://forum.openwrt.org/t/archer-c7-v2-massive-problems/
https://forum.openwrt.org/t/archer-c7-2-4-ghz-wireless-dies-in-24-48-hours/
Any clue ?