From owner-freebsd-stable@FreeBSD.ORG Fri Nov 30 07:48:06 2007 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B986416A417 for ; Fri, 30 Nov 2007 07:48:06 +0000 (UTC) (envelope-from vnovy@vnovy.net) Received: from slimak.dkm.cz (smtp.dkm.cz [62.24.64.34]) by mx1.freebsd.org (Postfix) with SMTP id 000BA13C4F4 for ; Fri, 30 Nov 2007 07:48:05 +0000 (UTC) (envelope-from vnovy@vnovy.net) Received: (qmail 43209 invoked by uid 0); 30 Nov 2007 07:21:25 -0000 Received: from r5o16.net.upc.cz (HELO vn.chello.upc.cz) (86.49.14.16) by smtp.dkm.cz with SMTP; 30 Nov 2007 07:21:24 -0000 Message-ID: <474FB9E5.9090208@vnovy.net> Date: Fri, 30 Nov 2007 08:21:09 +0100 From: Vitezslav Novy User-Agent: Thunderbird 2.0.0.6 (X11/20070924) MIME-Version: 1.0 To: freebsd-stable@freebsd.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: 7.0 BETA3 - slow TCP upload (TSO related?) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Nov 2007 07:48:06 -0000 Hello, my configuration is kernel GENERIC em0: flags=8843 metric 0 mtu 1500 options=18b ether 00:19:d1:0f:1c:18 inet 86.49.14.16 netmask 0xffffff00 broadcast 86.49.14.255 media: Ethernet autoselect (100baseTX ) status: active and standard "open" ipfw firewall and natd -u -s -m -d -dynamic -n em0 I experience very slow TCP upload from this host - cca 50kbps. I have some debug prints in kernel (mostly in ip_output and ipfw log) and I see: 1/ outgoing packet appears in ip_output with ip_len 2924 and m->pkthdr.csum_flags=1 2/ is diverted by firewall 3/ Packet appears immediately again in ip_output with ip_len 2924 and m->pkthdr.csum_flags=1 4/ Packet is accepted by firewall and dropped by ip_output with error 40 EMSGSIZE 5/ After cca 0.4s (tcp retransmit timeout?) new packet appears in ip_output with ip_len 1488 and m->pkthdr.csum_flags=1 6/ is successfully diverted and accepted by ipfw and sent to wire. 7/ after tcp ack is received new packet appears in ip_output with ip_len 2924 and everything repeats Packets are not changed by natd, beacause have src address of em0. nat Upload has normal speed (512kbps) if I unset TSO on interface OR set net.inet.tcp.tso=0 OR (strange thing) delete ipfw divert rule If necessary I will collect and send more info. vita