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Date: Wed, 28 May 2003 15:19:18 -0400 (EDT)
From: Garrett Wollman <wollman@lcs.mit.edu>
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To: Igor Sysoev <is@rambler-co.ru>
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cc: freebsd-net@freebsd.org
Subject: Re: turning off TCP_NOPUSH
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<<On Wed, 28 May 2003 22:22:14 +0400 (MSD), Igor Sysoev <is@rambler-co.ru> said:

> As I understand if the data in the send buffer is bigger than MSS it means
> that TCP stack has some reason not to send it and this reason is not
> TF_NOPUSH flag.  Am I wrong ?

If TCP is for some reason prohibited from sending (i.e., the flow
control or congestion control is closed), then tcp_output() will do
nothing (except perhaps send a window update if necessary).

If TCP is allowed to send data, then tcp_output() will send the data
immediately, which is what we want.

-GAWollman