Highest frequency of ESPNOW data transfer

[trustmiao]

while we are testing the highest fps of sending one byte through ESPNOW. We could n't even stably sending at 30fps. Worst will be around 7-9 fps, happen once couple second. The master will show this message once in couple second:

Send Status: Success
Sending: 124
E (16662) wifi: esf_buf: t=3 l=40 max:8, alloc:8 no eb
Send Status: ESP_ERR_ESPNOW_NO_MEM
Last Packet Sent to: 30:ae:a4:84:03:89
Last Packet Send Status: Delivery Success

though send status is success, the message wasn't delivered.

here are the questions
1. Is this the real limit of espnow?
2. how can we get failure flag like "E (16662)...." so that we could resend
3. what is the best way to send high frequency data, such as 60 fps.

[littlesky]

1. Is this the real limit of espnow?
—— ESPNOW data is carried in action frame and the physical rate and memory for action frame is limited. So the throughput of ESPNOW data is limited.
2. how can we get failure flag like "E (16662)...." so that we could resend
—— The log represents lack of memory to send ESPNOW data. "ESP_ERR_ESPNOW_NO_MEM" is the failure flag.
3. what is the best way to send high frequency data, such as 60 fps.
—— For the physical rate and memory for ESPNOW data is limited, the throughput of ESPNOW data is not high. But we can improve it.