Re: Antw: Re: [lwip-users] TCP retransmissions and some general questions

[Matthias Weisser]

>>> Kieran Mansley <address@hidden> schrieb am 20.06.2007 um 13:41:
> On Wed, 2007-06-20 at 13:06 +0200, Matthias Weisser wrote:
>> >>> Kieran Mansley <address@hidden> schrieb am 20.06.2007 um 12:14:
>> > Were there any ACKs from the other side between the sending of the
>> > packet and its retransmission?  If so, it could be fast retransmission
>> 
>> No. There where no ACKs from the PC side.
>> BTW:
>> Its a simple echo server.
>> 
>> > and not a problem.  If not, it does seem a bit early.  Perhaps you could
>> > send a wireshark/ethereal capture file to illustrate the problem?
>> 
>> Attached to this mail you find a pcap file. 210 is the PC (echo
>> client) and 34 is the lwIP device running the echo server on port
>> 6666.
> 
> Hmm, I'd agree with you that it looks like something is wrong.  My first
> guess would be something to do with how the TCP timers are being called
> in your port, as it is that that controls the timing of retransmissions.

You are right. A had a quick look into the timer function calls in api/tcpip.c 
and they get called way to fast. What can be the case for that? In 
sys_arch_timeouts() I return a pointer to a sys_timeouts structure on a per 
thread basis (using something like thread local storage) and thats all. I also 
looked into the code where the actual waiting is done to realize the timeouts 
but I couldn't find it.

Another point is: Maybe I still call the wrong init functions of lwIP. Here is 
my init code:

    sys_init();
    mem_init();    
    memp_init();
    pbuf_init(); 
    netif_init();
    tcpip_init(NULL, NULL);
    lwip_socket_init();

    netif_add(&nif, &ipaddr, &netmask, &gw, NULL, ethernetif_init, 
tcpip_input);  
    netif_set_default(&nif);
    netif_set_up(&nif);

Is there anything missing? Or do I have to wait for tcpip_init to be done 
before calling any other functions of lwIP?

Matthias