From owner-freebsd-net Fri Sep 20 20:17:11 2002 Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DD5C437B401 for ; Fri, 20 Sep 2002 20:17:09 -0700 (PDT) Received: from out1.mx.nwbl.wi.voyager.net (out1.mx.nwbl.wi.voyager.net [169.207.3.119]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8989E43E42 for ; Fri, 20 Sep 2002 20:17:09 -0700 (PDT) (envelope-from silby@silby.com) Received: from pop1.nwbl.wi.voyager.net (pop1.nwbl.wi.voyager.net [169.207.2.115]) by out1.mx.nwbl.wi.voyager.net (Postfix) with ESMTP id 2C970E2926; Fri, 20 Sep 2002 22:17:09 -0500 (CDT) Received: from [10.1.1.6] (d177.as9.nwbl0.wi.voyager.net [169.207.133.243]) by pop1.nwbl.wi.voyager.net (8.10.2/8.10.2) with ESMTP id g8L3H8U86898; Fri, 20 Sep 2002 22:17:08 -0500 (CDT) Date: Fri, 20 Sep 2002 22:21:02 -0500 (CDT) From: Mike Silbersack To: Julian Elischer Cc: net@freebsd.org Subject: Re: Tcp question. In-Reply-To: Message-ID: <20020920221735.Q6684-100000@patrocles.silby.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Fri, 20 Sep 2002, Julian Elischer wrote: > 000221 C.ssh > B.916: . [tcp sum ok] ack 66194 win 24624 > nop,nop,timestamp 259781842 16260556> (DF) > (ttl 64, id 18252, len 52) > **why wait here**? > 003030 C.ssh > B.916: . [tcp sum ok] ack 68930 win 24624 > nop,nop,timestamp 259781842 16260556> (DF) > (ttl 64, id 18253, len 52) Ok, I now have a more constructive reply. (Having reread with an understanding of the timestamps... I hadn't used -ttt before.) tcp_output.c rev 1.53 sounds like it may be applicable to this case: Add a flag TF_LASTIDLE, that forces a previously idle connection to send all its data, especially when the data is less than one MSS. This fixes an issue where the stack was delaying the sending of data, eventhough there was enough window to send all the data and the sending of data was emptying the socket buffer. Problem found by Yoshihiro Tsuchiya (tsuchiya@flab.fujitsu.co.jp) Submitted by: Jayanth Vijayaraghavan Apply that to host B and see if it helps. Mike "Silby" Silbersack To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message