Concerning buffered send mode yes, however I asked about unbuffered send mode with a large user buffer.
On Thu, 2021-10-14 at 15:13 -0600, Gregory Nutt wrote: > > Do I understand correctly, that if I use unbuffered mode with a > large > > user buffer (say 64 KB), then RFC 1122 still may pause NuttX TCP > > stack > > if an odd number of TCP segments are constructed based on the 64 KB > > buffer? Thus 0.5 second delay may occur at the end of 64 KB buffer > > during the last segment > > With large user buffers like that there may be some pauses if the IOB > buffers are exhausted. > > But no, in general nothing pauses the buffered send. It will send > data > without receiving any ACKs at all, at least until a timeout occurs > (which > it shouldn't). Otherwise, the presence or lack of ACKs has no effect > on > the data transfer. > > The only effect of the ACK is (1) to update the ACKed sequence > number, and > (2) to free the buffers holding the ACKed data. Receiving the ACKs > is > important only to prevent retransmissions and to prevent running out > of IOBs
