[lwip-users] lwip 2.0.2 tcp_output() problem

[Sergio R. Caprile]

I can think of:
- your driver
- your FreeRTOS priorities/loop (aka your port)
- your application not freeing PBUFs properly
- not enough PBUFs

TCP buffers data when you call tcp_write() and sends when you call 
tcp_output(). If you follow the code with a debugger you can get up to 
the point where data is sent to the driver. Did you ? Does your data get 
stuck inside lwIP or inside your driver ? Did you log tcp_output 
debugging output ?

I can see it looks like TCP is waiting for the ACK to send more data, 
check if you are freeing properly and have enough memory assigned for 
these pbufs. What's on your rx side ? What's your tcp_sent() ? Other 
apps starving pbufs ?
The way you handle your pcbs is a bit cumbersome for me, I can't comment 
on that nor on FreeRTOS.