Missing network traffic

[yanshay]

I'm working on an application that uses ESP32S3 with Embassy. I'm running all wifi on the 2nd core, and have two tasks, one to send UDP packets and another to receive. Very little packet parsing is done on that 2nd core so it mostly doing the wifi work so it's not busy.

The packets received are either triggered by an external system or are responses to packets my app sent.

All in all its working, however I miss incoming packets from time to time. I noticed that when I miss packets these are responses to my sent packets, as if the application isn't able to get the packets fast enough after it sends its own packets.

I assume that if it takes time for embassy to switch from the send task to the receive task, in the mean time I'd expect packets received to be stored in the driver for when I try_receive them, but it seems packets are lost. There isn't that much traffic so I don't see a reason for packets to be lost because of the amount of traffic, I mean 10 UDP packets (and not large) a second would be an extreme case.

I noticed there are quite a few parameters that can be tuned in esp-wifi but they aren't documented well also in espressif docs. Any ideas on what parameters I should try to tune to resolve these issues or maybe other things I should look for to resolve these missing traffic issues?

[bjoernQ]

Running the esp-wifi on the second core is not much tested, yet. I could imagine this https://github.com/esp-rs/esp-wifi/blob/d200a167237f03cf63edce721a5f85fd65d2db84/esp-wifi/src/wifi/os_adapter_esp32s3.rs#L28-L39 could create issues.

Especially intr_matrix_set(0, intr_source, intr_num); - the zero here is the core. Do things get better if you temporarily set it to 1? If that helps, we should probably change it to check / use the current core