RE: [lwip-devel] New buffer management code (fwd)

[lukem . lwip]

On Thu, 4 Dec 2003, Zschocke, Florian wrote:
> I didn't fully understand what exactly our changes do but I'll have to say
> that it does sound promising. In our case we don't use lwIP "standalone" but
> integrated into a larger system which already has it's own buffer
> management. So we had to create a mapping between lwIP buffers and our
> buffers, not using the lwIP buffer space at all and mostly rewriting the
> pbuf_ functions. I haven't investigated in how far your changes would apply
> to our system but I'm sure that people could benefit from a buffer system
> which allowed to easily integrate into an external buffer management in some
> way.

We had previously hacked in a new pbuf type specific to our system, but it
tended to be ugly, and also added extra overheads to the other pbuf types
by requiring that we stored extra data for each structure.

The reason I've re-written this stuff is so that we want to be able to
build our system against a generic lwIP source tree, with all our platform
specific stuff in a separate source tree. These new modifications should
make this posssible, which will save much hassle in keeping lwIP
up-to-date.

I guess the next question I have is how to contribute this code? CVS
access would be the easiest probably, but I can send patches instead if
required.

I also have some code in the pipeline to remove some of the nasty
linear searches performed in lwIP, which profiling here has shown really
hurt performance for large numbers of connections (you spend all the time
looking for the connection's pcb). This is working with an old version of
lwIP, but like the pbuf changes, tends to touch large amounts of the
source tree.

--
Luke