lwip-users
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [lwip-users] tcp_enqueue problem, using socket:


From: Piero 74
Subject: Re: [lwip-users] tcp_enqueue problem, using socket:
Date: Thu, 20 Mar 2008 11:12:50 +0100

here THE LAST report.
i did the test using "manual sending" on sw on serial port....

after some clicks (...means.. after some quick send operation on uart, and, from lwip to pc tcp client) the problem appears:
i saw tcp retransmission with checksum error again!!!

Piero

2008/3/20, Piero 74 <address@hidden>:
here i attached another file from wireshark.
In this test packets are sent in serial port (read previouses posts) every 200ms and the problem doesn't happen.

i saw that when the parblom happens, wireshark capture packet with incorrect checksum....
but i don't know if it is related to the problem

I hope these reports can help someone to understand

Piero


2008/3/20, Piero 74 <address@hidden>:
here i attached a wireshark file...

I didn't understand what is the problem....
Anyone can explain me??

my ip board is 192.168.0.101
pc ip is 192.169.0.1


2008/3/20, Piero 74 <address@hidden>:


2008/3/20, Piero 74 <address@hidden>:
Ok... i will try to explain my test and the problem.
After i will post a network sniffer report.

I have a simple pc application (client) which read packet from server and show in a window.

My application in board whit lwip works using two task:
- the first task get paccket from serial port, at 115200 baud; packet has the delimiter, so, at the end of packet, this task send it on queue.
- the second task has a loop with a select on data received on socket, with a timeout of 50 ms: when timeout expired, loop on queue, get the packet from queue and call socket function send, and loop again

i did the test using very small packet (max 30 bytes), sending them on uart every 100 ms

After few packets, i saw lwip blocked: in particolar, the task which manage socket is blocked, i suppose in send function.
I saw that in this case, tcpip thread (i suppose) is looping in tcp_enqueue function, and in particolar i have: queuelen = TCP_SND_QUEUELEN, so, TCP_STATS_INC(tcp.memerr) is done.

i'm seeing that code loop in after memerr label in this function... some goto memerr are called!

i have options below this post.

i'm doing other test, i will post some report.

Piero






Attachment: test3.pcap
Description: Binary data


reply via email to

[Prev in Thread] Current Thread [Next in Thread]