Jon Even Corneliussen

Interniche Lite buffer problem

Discussion created by Jon Even Corneliussen on Apr 19, 2011
Latest reply on Nov 20, 2012 by Jonathan Lawry

Hi,

 

Im using the Interniche Lite stack from 2006(?). It came with the MCF52235 EVB. I'm having problems with

what seems to be packet buffers not getting freed.

 

After system startup i have 9 bigbufs and 5 small bufs free. Every minute or so i print the number of free buffers.

After some time, let's say 30 mins of traffic on the ethernet, the number of free bigbuffer goes down to 8 or 7.

Some time later (lets say another 30 mins) it goes down by one or two buffers more. Ultimaltily, I have no big buffers left for packet transmission,  which results in an udp_alloc error cant allocate a buffer for the packet to be sent. So, I'm thinking there must be a bug somewhere that causes this problem.

 

The system can run forever if the mcf52235 is simply receiving broadcasts (No need for PC server updating ARP table?).

But, when the system is running with packets directed directly to the uC IP address, the problem starts.

My theory is that when the top side computer must send directly to the board it needs to occationaly send an ARP request

to the board, and that this ARP sometimes causes a problem with the buffers/ buffer descriptors not getting freed.

 

Im not sure that it really is ARP related though. It may be something completely different, but I just wanted to know if anybody else has had similar problems?

 

 

Jon Even

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