Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 3 Sep 2002 02:54:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 3 Sep 2002 02:54:57 -0400 Received: from pizda.ninka.net ([216.101.162.242]:62161 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id ; Tue, 3 Sep 2002 02:54:56 -0400 Date: Mon, 02 Sep 2002 23:52:44 -0700 (PDT) Message-Id: <20020902.235244.64832172.davem@redhat.com> To: jros@ece.uci.edu Cc: scott.feldman@intel.com, linux-kernel@vger.kernel.org, linux-net@vger.kernel.org, haveblue@us.ibm.com, Manand@us.ibm.com, kuznet@ms2.inr.ac.ru, christopher.leech@intel.com Subject: Re: TCP Segmentation Offloading (TSO) From: "David S. Miller" In-Reply-To: References: <288F9BF66CD9D5118DF400508B68C4460283E564@orsmsx113.jf.intel.com> X-Mailer: Mew version 2.1 on Emacs 21.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 833 Lines: 19 From: "Jordi Ros" Date: Mon, 2 Sep 2002 21:58:32 -0700 i assume the mtu is ethernet 1500 Bytes, right? and that mss should be something much bigger than mtu, which gives the performance improvement shown in the numbers. The performance improvement comes from the fact that the card is given huge 64K packets, then the card (using the given ip/tcp headers as a template) spits out 1500 byte mtu sized packets. Less data DMA'd to the device per normal-mtu packet and less per-packet data structure work by the cpu is where the improvement comes from. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/