From owner-freebsd-current@FreeBSD.ORG Sat Nov 17 23:23:38 2007 Return-Path: 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 8AB5816A419; Sat, 17 Nov 2007 23:23:38 +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 4399F13C481; Sat, 17 Nov 2007 23:23:38 +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 BDFBB1E3378; Sat, 17 Nov 2007 18:23:30 -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 uVnhZXnIjoqC; Sat, 17 Nov 2007 18:23:29 -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 18:23:29 -0500 (EST) Date: Sat, 17 Nov 2007 18:23:29 -0500 (EST) From: Mike Andrews X-X-Sender: mandrews@mindcrime.int.bit0.com To: Kip Macy In-Reply-To: Message-ID: <20071117182232.T59492@mindcrime.int.bit0.com> References: <20071117003504.R31357@mindcrime.int.bit0.com> <20071117213316.499be43b@vlink.ru> <20071117170537.F59492@mindcrime.int.bit0.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: Denis Shaposhnikov , Mike Silbersack , Andre Oppermann , 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 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 17 Nov 2007 23:23:38 -0000 On Sat, 17 Nov 2007, Kip Macy wrote: > On Nov 17, 2007 2:33 PM, Mike Andrews wrote: >> On Sat, 17 Nov 2007, Kip Macy wrote: >> >>> On Nov 17, 2007 10:33 AM, Denis Shaposhnikov wrote: >>>> On Sat, 17 Nov 2007 00:42:54 -0500 (EST) >>>> Mike Andrews 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... > > Mike - > Denis' tcpdump output doesn't show oversized segments, something else > appears to be happening there. Can you post your tcpdump output > somewhere? URL sent off-list.