Re: [lwip-users] Acknowledge Problem

[Sergio R. Caprile]

>> Did you check that with a known-good application ?
> *Not yet.*

Well..., you should. Did I say 'should' ? You _must_

>> What version of lwIP are you using ?
> *We used lwip 1.4.1 and also
> source from git.savannah.gnu.org (commit #70f3e5e). In both versions
> the problem exists.*

I would say that "you experience this behaviour when running either 
version", I wouldn't blame lwIP for it, not yet.

>> Do you use an OS ? NO_SYS=?
> *FreeRTOS*

>> What API are you using ?
> *I have to check this.*

>> Do you honor the threading rules ?
> *I have to check this.*

Well, if you don't honor threading rules, you will experience all kind 
of strange and faulty behaviour, and that won't be lwIP's fault, so... 
you should start here.

>> Do you know there are web servers in the contrib tree ?
> *Yes, we are using netcon*


You are running a port over FreeRTOS, you should(must) have NO_SYS=0, 
basic functions must run on one thread, I mean, no rx interrupts and 
lwIP core on a thread. Netconn apps may run on a separate thread (but 
I'm not versed in netconn)
The delay you describe has been observed in some ports that poll the rx 
driver and forget to remove all frames from it (ST?)
The delays I observe are consistent with this, the server seems to 
answer "one frame off", and then in frame 57, an XID comes in and stacks 
one extra frame in the Eth controller memory, probably causing a frame 
loss, and later there ARP requests, what makes this even worse. I may be 
wrong, but...

You say you are using the 'netcon' webserver (do you mean 'netconn' ?)
However, your capture file shows the server responds with "Server: 
lwIP/1.3.1 (http://savannah.nongnu.org/projects/lwip)", and that belongs 
to fsdata.c, which is from the RAW API webserver. Besides, the netconn 
web server does not serve files.
You should know what you are using, in order to use it properly.

If you are indeed using the RAW API webserver, that server runs quite 
more than OK. If you are running 'a' netconn server, that server is not 
lwIP code.

Your problem, then, I bet, lies on a faulty port, please check what I 
already suggested you should check (and you did not).
If, after that, you still have problems, please open a new thread and 
include your API, RTOS and port provider description in the subject.