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Date: Sat, 16 Apr 2016 02:44:54 +0000
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From: "mike-karels.net (Mike Karels)" <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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mike-karels.net added a comment.


  I believe that the original code is wrong, and the change is not sufficient
  to fix it.  The retransmit timer should be running if and only if we have
  sent data into the receive window and are awaiting an ACK.  The persist
  timer should be running if and only if the retransmit timer is not running,
  and we have data to send that do not reasonably fit in the window.  If we
  get an ENOBUFS when sending data, we will already be running the retransmit
  timer.  If we drop an ACK on ENOBUFS, either we will receive more data and
  attempt another ACK, or the sender will time out and resend data.  Either
  will get the connection started again.  I believe lines 1552-1554 should
  simply be deleted.

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

EMAIL PREFERENCES
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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