[lwip-devel] [bug #50476] active open, ssthresh is really low with auto-tuning receiver

[Joel Cunningham]

Follow-up Comment #13, bug #50476 (project lwip):

I studied test_tcp_fast_rexmit_wraparound and it is making assumptions about
how many segments are transmitted upon ACKing the first segment when multiple
segments are queued for output (waiting on the in-flight data to decrease). 
It's not clear to me whether the test relied on tcp_alloc() to keep ssthresh
at 0 (enforcing congestion avoidance) or if it was working by accident until
my changes.

The attached patch enforces congestion avoidance for this test by setting
pcb->ssthresh to pcb->cwnd. The test passes now.

I also looked at the other tests and did not see the same assumption, but some
have the txcount checks commented out (see test_tcp_fast_retx_recover) so it's
not clear.  The others passed without any modification



(file #39955)
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Additional Item Attachment:

File name: 0001-Fix-unit-test-with-assumed-congestion-avoidance.patch Size:1
KB


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