Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263922AbTFPQFp (ORCPT ); Mon, 16 Jun 2003 12:05:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263980AbTFPQFp (ORCPT ); Mon, 16 Jun 2003 12:05:45 -0400 Received: from e31.co.us.ibm.com ([32.97.110.129]:44751 "EHLO e31.co.us.ibm.com") by vger.kernel.org with ESMTP id S263922AbTFPQFo (ORCPT ); Mon, 16 Jun 2003 12:05:44 -0400 Message-ID: <3EEDEDA1.7010401@us.ibm.com> Date: Mon, 16 Jun 2003 09:17:37 -0700 From: Nivedita Singhvi User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.2.1) Gecko/20021130 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Herman Dierks CC: "David S. Miller" , ltd@cisco.com, anton@samba.org, haveblue@us.ibm.com, scott.feldman@intel.com, dwg@au1.ibm.com, linux-kernel@vger.kernel.org, Nancy J Milliner , Ricardo C Gonzalez , Brian Twichell , netdev@oss.sgi.com Subject: Re: e1000 performance hack for ppc64 (Power4) References: In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2525 Lines: 60 Herman Dierks wrote: > Look folks, we run 40 to 48 GigE adapters in a p690 32 way on AIX and > they basically all run at full speed so let me se you try that on most of > these other boxes you are talking about. Same adapter, same hardware > logic. FWIW, I think that's pretty cool. Not easy to do. :) > For larger packets, like jumbo frames or large send (TSO), the few added > DMA's is not an issue as the packets are so large the DMA soon get aligned > and are not an issue. With TSO being the default, the small packet case > becomes less important anyway. Its more an issue on 2.4 where TSO is not > provided. We also want this to run well if someone does not want to use > TSO. Slightly off-topic, but TSO being enabled and TSO being used are two different things, right? Ditto jumbo frames..How often is this the actual env in real world situations? I'm concerned that this is more typical of development testing/performance testing environments. > Its only the MTU 1500 case with non-TSO that we are discussing here so Which still is the pretty important case, I think.. > copying a few bytes is really not a big deal as the data is already in > cache from copying into kernel. If it lets the adapter run at speed, thats > what customers want and what we need. Yep. > Granted, if the HW could deal with this we would not have to, but thats not > the case today so I want to spend a few CPU cycles to get best performance. > Again, if this is not done on other platforms, I don't understand why you > care. Still would be nice to put in the best solution possible, i.e. address it for the broadest set of affected pieces and minimizing the impact.. > If we have to do this for PPC port, fine. I have not seen any of you Hope it doesn't have to come to that..It would be nice to see it in the mainline kernel. Regardless of platform, distro, etc.. these users are still people who are taking the time, the effort to adopt Linux and sometimes in environments and situations that are pretty critical. Change and innovation are difficult activities to engage in some places, and anything we can do to make this a no-brainer solution for them, and their decisions shine, thats gotta be worth something to go the extra mile for :) thanks, Nivedita - 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/