I have an Asus RT-N16 with shibby firmware 1.28.0000 MIPSR2-107 K26 USB AIO.
When I transfer many data between 2 VLANs, the CPU usage rises up to 99%. About 90% is taken from the process "ksoftirqd". The data transfer rate is about 150 MBit/s and the router becomes laggy.
In the same VLAN CPU usage only rises to 10% and the data transfer rate goes up to 850 MBit/s.
Is this normal (hardware limitation?) or a bug?