[lwip-users] losing input packets and repeated acks

[Carl D. Blake]

I'm having a problem with the input side of TCP.  I am receiving a
fairly large amount of data (approximately 1 megabyte).  Periodically,
(about every 50,000 to 160,000 bytes) the transfer hangs.  The
transmitter is waiting for an ack from my lwip device and keeps retrying
a packet.  Several seconds later my lwip device suddenly responds with
several acks of a packet that has already been acked.  I've seen the
system do this for up to 15 seconds before my lwip device finally acks
the packet that is being retried.  After that the transmission proceeds
normally for another 50,000 to 160,000 bytes and then it happens again.

I've attached my lwipopts.h file and a tcpdump trace.

lwipopts.h
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mptst
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