roundrobin mode traffic reduction

[mzky]

Is it normal or abnormal for the network port team roundrobin mode to bind ports that are not connected to the network cable to cause a decrease in traffic? （at libteam1.31~1.32）

for example（use iperf3）：
eth0 eth1 are connected to the network, while eth2 eth3 eth4 eth5 are not connected to the network

1. Bind Ethernet ports eth0 eth1 to the polling team
   Normal traffic
   

2. Bind Ethernet ports eth0 eth1 eth2 to the polling team
   Total traffic decreased by 20%
   

3. Bind Ethernet ports eth0 eth1 eth2 eth3 to the polling team
   Total traffic decreased by 50%
   

4. Bind Ethernet ports eth0 eth1 eth2 eth3 eth4 to the polling team
   Total traffic decreased by 30%
   

5. Bind Ethernet all ports to the polling team
   The total traffic has decreased by 50%, with the same effect as the 3 item

Thanks.