From owner-freebsd-current@FreeBSD.ORG  Sat Nov 17 22:33:25 2007
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 8739516A418
	for <freebsd-current@freebsd.org>; Sat, 17 Nov 2007 22:33:25 +0000 (UTC)
	(envelope-from mandrews@bit0.com)
Received: from mindcrime.bit0.com (bit0.com [207.246.88.211])
	by mx1.freebsd.org (Postfix) with ESMTP id 4922B13C4D9
	for <freebsd-current@freebsd.org>; Sat, 17 Nov 2007 22:33:24 +0000 (UTC)
	(envelope-from mandrews@bit0.com)
Received: from localhost (localhost.bit0.com [127.0.0.1])
	by mindcrime.bit0.com (Postfix) with ESMTP id B24E81E3379;
	Sat, 17 Nov 2007 17:33:15 -0500 (EST)
X-Virus-Scanned: amavisd-new at bit0.com
Received: from mindcrime.bit0.com ([127.0.0.1])
	by localhost (mindcrime.int.bit0.com [127.0.0.1]) (amavisd-new,
	port 10024)
	with ESMTP id i1irSgkbd7Kv; Sat, 17 Nov 2007 17:33:14 -0500 (EST)
Received: from localhost (localhost.bit0.com [127.0.0.1])
	(using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
	(No client certificate requested)
	by mindcrime.bit0.com (Postfix) with ESMTP;
	Sat, 17 Nov 2007 17:33:14 -0500 (EST)
Date: Sat, 17 Nov 2007 17:33:14 -0500 (EST)
From: Mike Andrews <mandrews@bit0.com>
X-X-Sender: mandrews@mindcrime.int.bit0.com
To: Kip Macy <kip.macy@gmail.com>
In-Reply-To: <b1fa29170711171308x62a6371dnbb939748c5c59ae2@mail.gmail.com>
Message-ID: <20071117170537.F59492@mindcrime.int.bit0.com>
References: <20071117003504.R31357@mindcrime.int.bit0.com>
	<20071117213316.499be43b@vlink.ru>
	<b1fa29170711171308x62a6371dnbb939748c5c59ae2@mail.gmail.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
Cc: Denis Shaposhnikov <dsh@vlink.ru>, Mike Silbersack <silby@freebsd.org>,
	Andre Oppermann <andre@freebsd.org>, freebsd-current@freebsd.org
Subject: Re: bizarre em + TSO + MSS issue in RELENG_7
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 17 Nov 2007 22:33:25 -0000

On Sat, 17 Nov 2007, Kip Macy wrote:

> On Nov 17, 2007 10:33 AM, Denis Shaposhnikov <dsh@vlink.ru> wrote:
>> On Sat, 17 Nov 2007 00:42:54 -0500 (EST)
>> Mike Andrews <mandrews@bit0.com> wrote:
>>
>>> Has anyone run into problems with MSS not being respected when using
>>> TSO, specifically on em cards?
>>
>> Yes, I wrote about this problem on the beginning of 2007, see
>>
>>     http://tinyurl.com/3e5ak5
>>
>
> if_em.c:3502
>        /*
>         * Payload size per packet w/o any headers.
>         * Length of all headers up to payload.
>         */
>        TXD->tcp_seg_setup.fields.mss = htole16(mp->m_pkthdr.tso_segsz);
>        TXD->tcp_seg_setup.fields.hdr_len = hdr_len;
>
>
> Please print out the value of tso_segsz here. It appears to be being
> set correctly. The only thing I can think of is that t_maxopd is not
> correct. As tso_segsz is correct here:


It repeatedly prints 1368 during a 1 meg file transfer over a connection 
with a 1380 MSS.  Any other printf's I can add?  I'm working on a web page 
with tcpdump / firewall log output illustrating the issue...