I have made some progress. I was out-to-lunch on the accumulation of unacked packets causing the memory leak. I still don't understand were the memory leak is coming from.
in an attempt to debug the memory I enabled MEMP_SANITY_CHECK and reduced MEM_SIZE to 3200. And now for some reason this seems to fix things. I have been able to run it for more than 10 times longer than usual and there has been no memory leakage. Although I am happy to just build with MEMP_SANITY_CHECK I am sure this is a band-aid. Does anyone have any ideas why this could fix my memory leak? Mat schneiderham wrote: > > Hi, > I have a system that works very well thanks to the lwIP stack. Thanks for > all the contributors. However, I have one slight problem that is beyond > me that I would appreciate help with. > > My system streams data over TCP to a LabView application. If I send 1336 > bytes per packet every 20ms (50 packets per second) all works well. > However, If I reduce my report rate to every 200ms (5 packets per second) > there is an gradual accumulation of "unack" packets. If I stop the > streaming these packets are never acknowledged. It is my belief that the > packets are delivered to the labview application but the ack message is > missed. (I have previously looked for missing data and have not found > any) > > Here are a couple of my configurations: > MEM_ALIGNMENT 4 > MEM_SIZE 4 * 6400 > TCP_WND 8192 > TCP_MSS 3000 > TCP_SND_BUF 4 * TCP_MSS > > > An observation I found was that the sent callback routine is called 1/2 as > many times as the number of TCP_write() commands (and subsequent receives > on the labView side) were sent at the max rate of 50 packets per second. > Conversely, at 5 packets per second the number of the number of times the > sent callback routine was called equaled the number of sent and received > packets except that the the sent callback routine would gradually slide > indicating that there were missing acknowledgments. > > If anyone could suggest any reasons why I am missing acknowledgments at > reduced packet sending rates that would be helpful and appreciated. > > Mat > > -- View this message in context: http://www.nabble.com/TCP-mem-leak-with-accumalated-unacked-messages-tp25182251p25199571.html Sent from the lwip-users mailing list archive at Nabble.com. _______________________________________________ lwip-users mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/lwip-users
