Will replacing the P4 program interrupt the switch when it is running?


I want to know what effect will the replacement of P4 program have on the switch when the switch is running?
I do experiments in bmv2. When the switch performs forwarding tasks, use simple_ switch_ CLI: The “load_new_config_file” and “swap_configs” commands switch the compiled P4 program. I find that there is no packet loss, and the throughput is almost unchanged. I think that replacing the data plane program should temporarily interrupt the running of the switch, but it seems that this is not the case.

If you send packets slowly enough, or there is a gap in time when the switch receives packets that is longer than the time it takes to load the new P4 program, then you will not notice any packet loss due to reloading the P4 program on the device.

If you send packets quickly enough, I believe you almost certainly will notice packet loss during the reloading of the P4 program.