Re: [lwip-users] [raw] configure lwip tcp tx pbuf

[D.C. van Moolenbroek]

On 2/28/2017 19:07, François Thierry wrote:
> - #define PBUF_POOL_SIZE 256
> - #define PBUF_POOL_BUFSIZE 1700
[..]
> - The following line indicates me that the pbuf will be placed in RAM
> tcp_pbuf_prealloc(layer, length, mx, os, pcb, api, fst) 
> pbuf_alloc((layer), (length), PBUF_RAM)

Just to add to Simon's post: please be aware that PBUF_RAM allocations 
never draw from the PBUF POOL that you've defined above. If you want 
that to happen, define a custom pool instead, and (if relevant) avoid 
PBUF_POOL allocations in your own code. Otherwise you'll need a heap (ie 
MEM_SIZE).

As far as I can tell, although I'd love to be corrected, there is no way 
to have a statically sized pool that is used for both PBUF_RAM and 
PBUF_POOL allocations.

David