From owner-svn-src-all@FreeBSD.ORG Mon Oct 29 13:18:15 2012 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 7317CE72 for ; Mon, 29 Oct 2012 13:18:15 +0000 (UTC) (envelope-from andre@freebsd.org) Received: from c00l3r.networx.ch (c00l3r.networx.ch [62.48.2.2]) by mx1.freebsd.org (Postfix) with ESMTP id C51178FC1B for ; Mon, 29 Oct 2012 13:18:13 +0000 (UTC) Received: (qmail 39879 invoked from network); 29 Oct 2012 14:55:08 -0000 Received: from c00l3r.networx.ch (HELO [127.0.0.1]) ([62.48.2.2]) (envelope-sender ) by c00l3r.networx.ch (qmail-ldap-1.03) with SMTP for ; 29 Oct 2012 14:55:08 -0000 Message-ID: <508E8211.5020903@freebsd.org> Date: Mon, 29 Oct 2012 14:18:09 +0100 From: Andre Oppermann User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:16.0) Gecko/20121010 Thunderbird/16.0.1 MIME-Version: 1.0 To: Andre Oppermann Subject: Re: svn commit: r242251 - head/sys/netinet References: <201210281730.q9SHUT6U062773@svn.freebsd.org> In-Reply-To: <201210281730.q9SHUT6U062773@svn.freebsd.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 29 Oct 2012 13:18:15 -0000 On 28.10.2012 18:30, Andre Oppermann wrote: > Author: andre > Date: Sun Oct 28 17:30:28 2012 > New Revision: 242251 > URL: http://svn.freebsd.org/changeset/base/242251 > > Log: > When SYN or SYN/ACK had to be retransmitted RFC5681 requires us to > reduce the initial CWND to one segment. This reduction got lost > some time ago due to a change in initialization ordering. > > Additionally in tcp_timer_rexmt() avoid entering fast recovery when > we're still in TCPS_SYN_SENT state. Oops, this was the wrong commit message for this change. Here is the correct one: Defer sending an independent window update if a delayed ACK is pending saving a packet. The window update then gets piggy-backed on the next already scheduled ACK. I've forced commit r242311 with some grammar fixes to provide this information. -- Andre > MFC after: 2 weeks > > Modified: > head/sys/netinet/tcp_output.c > > Modified: head/sys/netinet/tcp_output.c > ============================================================================== > --- head/sys/netinet/tcp_output.c Sun Oct 28 17:25:08 2012 (r242250) > +++ head/sys/netinet/tcp_output.c Sun Oct 28 17:30:28 2012 (r242251) > @@ -551,10 +551,14 @@ after_sack_rexmit: > * max size segments, or at least 50% of the maximum possible > * window, then want to send a window update to peer. > * Skip this if the connection is in T/TCP half-open state. > - * Don't send pure window updates when the peer has closed > - * the connection and won't ever send more data. > + * > + * Don't send an independent window update if a delayed > + * ACK is pending (it will get piggy-backed on it) or the > + * remote side already has done a half-close and won't send > + * more data. > */ > if (recwin > 0 && !(tp->t_flags & TF_NEEDSYN) && > + !(tp->t_flags & TF_DELACK) && > !TCPS_HAVERCVDFIN(tp->t_state)) { > /* > * "adv" is the amount we can increase the window, > >