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Date: Mon, 18 Apr 2016 01:29:50 +0000
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From: "sepherosa_gmail.com (Sepherosa Ziehau)" <phabric-noreply@FreeBSD.org>
Reply-to: D5872+325+9dea0574509cdbb3@reviews.freebsd.org
Subject: [Differential] [Commented On] D5872: tcp: Don't prematurely drop
 receiving-only connections
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sepherosa_gmail.com added a comment.


  In https://reviews.freebsd.org/D5872#127063, @jtl wrote:
  
  > Doesn't tp->t_rxtshift get updated on a successful send? If not, I think that is what we should be fixing.
  >
  > Personally, I think a connection should drop if we aren't able to send any ACKs for 350 seconds.
  
  
  It's t_shift >= 12 killing the connection, since no one actually stops the timer/performs RTT update for ACK if ENOBUFS happens on a receiving only connections.  So intermittent (not continuous) failures to transmit ACK due to ENOBUFS will kill a long living receiving only connection eventually.

REVISION DETAIL
  https://reviews.freebsd.org/D5872

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To: sepherosa_gmail.com, network, glebius, lstewart, adrian, delphij, decui_microsoft.com, honzhan_microsoft.com, howard0su_gmail.com, freebsd-net-list, transport, jtl, hiren
Cc: mike-karels.net, jtl