From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Huang Subject: Re: LRO restructuring? Date: Wed, 18 Feb 2009 19:25:49 +0000 (UTC) Message-ID: References: <20080811.175434.215224347.davem@davemloft.net> <20080812010004.GD18547@gondor.apana.org.au> <48A0E7A3.6030200@hp.com> <20080811.183913.09225669.davem@davemloft.net> <20080812015321.GA19011@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from main.gmane.org ([80.91.229.2]:41724 "EHLO ciao.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752097AbZBRTaJ (ORCPT ); Wed, 18 Feb 2009 14:30:09 -0500 Received: from root by ciao.gmane.org with local (Exim 4.43) id 1LZs7O-0000Ux-9o for netdev@vger.kernel.org; Wed, 18 Feb 2009 19:30:02 +0000 Received: from 66.151.55.131 ([66.151.55.131]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 18 Feb 2009 19:30:02 +0000 Received: from jamesclhuang by 66.151.55.131 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 18 Feb 2009 19:30:02 +0000 Sender: netdev-owner@vger.kernel.org List-ID: Hi Herbert, Any idea when this LRO restructuring work will be done? Making LRO available even when ip forwarding is enabled will significantly improve performace of network appliances in the data path. I have some questions on this: (1) Based on the emails in this thread, I suppose you are going to keep the original length of each segment you coalesced into the big packet and use that info to segment the big packet on the output path. In case the packet was modified by an appliance in the path and the total length is changed (e.g. NAT on ftp control packets), should the corresponding segment length info also get updated? This same question also applies to the checksums. (2) Do you make sure all of the segments to be coalesced have the same DF bit? (3) I think bridged packets should not be LROed. Whether a packet is bridged or not can be based on the L2 MAC destination address. Is this how it is done? (4) Does LRO work only for IPv4? Any plan to extend it to support IPv6? Thanks, James Huang