[lwip-users] MEMP_NUM_TCP_PCB effect on TLS and HTTPD

[Mário Luzeiro]

Hello all,

I have a HTTPD via mbedTLS all is going OK except I have issues with multiple 
connections from browser requests (browsers send multiple connection at same 
time to faster load the website). Sometimes it cannot make the connection and 
cannot load all external files in the webpage.

I was playing with MEMP_NUM_TCP_PCB and I got some behavior I cannot explain 
and looking for your help.

MEMP_NUM_TCP_PCB 5
https://i.imgur.com/6oNwz15.png
File loads in 27s

MEMP_NUM_TCP_PCB 12
https://i.imgur.com/c449wIz.png
note: TTFB means Time To First Byte
File loads in 420ms

So if I set an higher MEMP_NUM_TCP_PCB value it all times will take that slow 
400ms

does anyone could explain what could MEMP_NUM_TCP_PCB influence in this case?

Mario Luzeiro