TCP/IP Socket Connections

Sorry, correction to my last post, cannot create more than three connections, not sockets.

In my config file:

Ip.socketMaxConnections = 16;

The TeraTerm will report 'connection refused' when create 4th connections. Why?

Luke, Rongbiao,

Can you provide details of your application configurations?  What device and platforms are you using?

It looks like you are with separate organizations, but both in the same city, so I wonder if this is the same project, or different?

The default for Ip.socketMaxConnections is 8, so there should be no fixed limitation at 4.  It is a guess, but maybe you don’t have enough free RAM to support additional connections?

Scott

Hi, Scott,

we are working on the same project.

We are using LM3S9B96 with CCS Version: 5.3.0.00090 and Tirtos_1-01_00_25. I already changed the Ip.socketMaxConnections to 16. and I tried to increase the HeapMem from x5000 to x6000 but still no success.

I couldn't debug into the NDK API like accept(). So I don't know where the NDK refused the new connection.

Any suggestion welcome.

Thanks.

Rongbiao,

OK, thanks for clarifying.

I received two suggestions by internal email:

1) You might be hitting a limit due to the Telnet module configuration(?)  The default number of connections for the server is 8, but maybe that has been reduced in your configuration?  For example:

var Telnet = xdc.useModule('ti.ndk.config.Telnet');

/* add a Telnet server (IPv6) */
var telnetParams = new Telnet.Params();
telnetParams.maxCon = ???;
telnetParams.callBackFxn = '&ConsoleOpen';
var telnet = Telnet.create(telnetParams);

If you add a print statement like below to your config file you should be able to see what is configured for your application:

print(“--------> telnet max con = “ + telnetParams.maxCon);


2) You should review this wiki page regarding ways to tune memory usage by the network stack: http://processors.wiki.ti.com/index.php/TI-RTOS_Networking_Stack_Memory_Usage\


Scott

Hi, Scott,

In my project, Telnet is not enabled. We are using TCP/IP. The Ip.socketMaxConnections = 8;

I'll try to tune the memory usage soon.

Rongbiao

Hi Rongbiao,

OK, thanks.

A couple of other things to try… is the app failing at accept()?  If so, what is the return code?

If failing elsewhere, what is the failure code reported?

Also, once a connect failure happens, can you call mmCheck() and send that output?

Thanks,
Scott

Hi, Scott,

Yes. It is failed at accept(). but it doesn't return anything.

I'll try mmCheck() and see what will happen.

Thanks,

Rongbiao

Does accept() return a non-negative integer value?  Or INVALID_SOCKET?

Hi, Scott,

I'm coming back to work on this issue again.

The current situration is: the PC app. connect to MC and communicate with it. When PC app. exit, the connection broken. The PC app. restart and re-connect to MC still OK. Until PC app. re-connect to MC the 5th time, the MC crushed and report the following:

---------------------

Network Added: If-1:192.168.252.200

TCPdaemon: Creating thread clientfd = 536927860

tcpRX: start clientfd = 0x2000de74

tcpTX: start clientfd = 0x2000de74

00047.200 TCP: Retransmit Timeout

tcpRx stopped clientfd = 0x2000de74

TCPdaemon: Closing connection ...

TCPdaemon: New Socket OK

TCPdaemon: New bind OK

TCPdaemon: Listening...

TCPdaemon: Creating thread clientfd = 536928884

tcpRX: start clientfd = 0x2000e274

tcpTX: start clientfd = 0x2000e274

00079.800 TCP: Retransmit Timeout

tcpRx stopped clientfd = 0x2000e274

TCPdaemon: Closing connection ...

TCPdaemon: New Socket OK

TCPdaemon: New bind OK

TCPdaemon: Listening...

TCPdaemon: Creating thread clientfd = 536929908

tcpRX: start clientfd = 0x2000e674

tcpTX: start clientfd = 0x2000e674

00275.600 TCP: Retransmit Timeout

tcpRx stopped clientfd = 0x2000e674

TCPdaemon: Closing connection ...

TCPdaemon: New Socket OK

TCPdaemon: New bind OK

TCPdaemon: Listening...

TCPdaemon: Creating thread clientfd = 536930932

tcpRX: start clientfd = 0x2000ea74

tcpTX: start clientfd = 0x2000ea74

00303.100 TCP: Retransmit Timeout

tcpRx stopped clientfd = 0x2000ea74

TCPdaemon: Closing connection ...

TCPdaemon: New Socket OK

ti.sysbios.heaps.HeapMem: line 307: out of memory: handle=0x20015134, size=1608

00316.720 mmBulkAlloc(): could not allocate memory.

00316.720 out of memory: handle=0x20011c64, size=536943768

00316.720 SBNew: Buffer OOM

Network Removed: If-1:192.168.252.200

TCPdaemon: New bind OK

TCPdaemon: Listening...

------------------------

The LM3S9D96 tcp_echo example shows that the 6th connection will reuse the first connection handle and go on:

--------

Starting the TCP Echo example

System provider is set to SysMin. Halt the target and use ROV to view output.

Network Added: If-1:192.168.252.200

tcpHandler: Creating thread clientfd = 536909700

tcpWorker: start clientfd = 0x20009784

00014.800 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009784

tcpHandler: Creating thread clientfd = 536910212

tcpWorker: start clientfd = 0x20009984

00024.900 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009984

tcpHandler: Creating thread clientfd = 536910724

tcpWorker: start clientfd = 0x20009b84

00034.700 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009b84

tcpHandler: Creating thread clientfd = 536911236

tcpWorker: start clientfd = 0x20009d84

00042.400 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009d84

tcpHandler: Creating thread clientfd = 536911748

tcpWorker: start clientfd = 0x20009f84

00052.200 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009f84

tcpHandler: Creating thread clientfd = 536909700

tcpWorker: start clientfd = 0x20009784

00078.700 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009784

tcpHandler: Creating thread clientfd = 536910212

tcpWorker: start clientfd = 0x20009984

00089.500 TCP: Retransmit Timeout

tcpWorker stop clientfd = 0x20009984

tcpHandler: Creating thread clientfd = 536910724

tcpWorker: start clientfd = 0x20009b84

------------------

Is there anyway for me to set this magic number of connections so I can limit it to 4 or less?

Is there another way for me to wait longer until the connection release all its resourses?

Regards,

Ron

This memory issue has been solved. My code has the same beheaver like the tcp-echo does.

The Memory issue was caused by the BIOS does NOT 'delete terminated tasks' even I saw the OPTION is checked. By enable the Idle Task, The 'delete terminated tasks' will work and eliminated the memory issue.