Re: [lwip-users] LwIP 1.3.2 -> 1.4.0: Huge RAM increase for PPP use

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Marco Jakobs wrote:
> updating a project from LwIP 1.3.2 to 1.4.0 without the use of PPP did a
> minor increase of the used RAM of a few hundret bytes, which is no
> problem on my limited microcontroller environment.
>
> But a project which is using PPP (PPPoS) with LwIP did a jump up of
> around 3kByte and more by the update from LwIP 1.4.0 to 1.3.2. This
> really killed my free memory.

Which compiler are you using? Can you provide some kind of map file for 
the 4 compiled versions (1.3.2 vs. 1.4.0; PPP vs. no PPP) so I can 
compare them? That would be the fastest way to see why RAM usage 
increased and what we can do about it.

Just to confirm Paul: I'm not aware of any major increase in RAM usage, 
too. But then again, in the targets where RAM is an issue, I only 
compile a very small subset of the complete code. Plus my MAP analyser 
for MSVC (which is what I use to develop/test lwIP) is not too good...

> What are the changes which uses this huge amount of memory in LwIP 1.4.0
> while using PPP?

This seems to be unknown, but I'm willing to dig into this and work on 
it to reduce RAM usage, if there's no downside.

Simon