Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262918AbUKRT2t (ORCPT ); Thu, 18 Nov 2004 14:28:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262917AbUKRTOo (ORCPT ); Thu, 18 Nov 2004 14:14:44 -0500 Received: from fmr12.intel.com ([134.134.136.15]:40064 "EHLO orsfmr001.jf.intel.com") by vger.kernel.org with ESMTP id S262905AbUKRTJD convert rfc822-to-8bit (ORCPT ); Thu, 18 Nov 2004 14:09:03 -0500 X-MimeOLE: Produced By Microsoft Exchange V6.5.7226.0 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 8BIT Subject: RE: [Bonding-devel][PATCH]Zero Copy Transmit Support (Update) Date: Thu, 18 Nov 2004 11:02:12 -0800 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [Bonding-devel][PATCH]Zero Copy Transmit Support (Update) Thread-Index: AcTITHNPBHIfGinGQ8GOOQILPIIIqQFUYiww From: "Godse, Radheka" To: "David S. Miller" Cc: , , , X-OriginalArrivalTime: 18 Nov 2004 19:02:14.0292 (UTC) FILETIME=[1D948D40:01C4CDA1] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3632 Lines: 91 > - > + > + /* We let the bond device publish all hardware > + * acceleration features possible. This is OK, > + * since if an skb is passed from the bond to > + * a slave that doesn't support one of those > + * features, everything is fixed in the > + * dev_queue_xmit() function (e.g. calculate > + * check sum, linearize the skb, etc.). > + */ This is very inefficient if the bond slaves don't support these features. I believe you when you say you saw improvement in the case where the slaves do support TSO, but if you test a non-TSO slave case I bet you'll see a marked decrease in system utilization at least. ... Note: 2.6.2 patch enables Zero Copy Transmit support by default while registering the bond device... but, I continue to see better CPU utilization (~50% improvement) when this patch was tested in various scenarios(see data below). Test results are from a dual Itanium 2 1.4GHz system but I saw a similar trend on a PIII Xeon 550MHz x 8 system. bond-patch-2.6.1 and 82546EB Copper NICs with hardware acceleration support, Test results with TSO on and off ETH1 ETH2 Throughput/Performance System Utilization on off 1870 35 % on on 1870 35 % off off 1871 34 % bond-patch-2.6.2 and 82546EB Copper NICs with hardware acceleration support, Test results with TSO on and off ETH1 ETH2 Throughput/Performance System Utilization on off 1879 14 % on on 1880 14.08 % off off 1879 13 % ------------------------------------------------------------------ bond-patch-2.6.1 and 82543GC NICs without hardware support for TSO ETH1 ETH2 Throughput/Performance System Utilization off off 1815 36.85 % bond-patch-2.6.2 and 82543GC NICs without hardware support for TSO ETH1 ETH2 Throughput/Performance System Utilization off off 1848 11.85 % ------------------------------------------------------------------ bond-patch-2.6.1, and one 82546EB NIC with & one 82543GC NIC without hardware support for TSO ETH1 ETH2 Throughput/Performance System Utilization on off 1817 30.69 % bond-patch-2.6.2, and one 82546EB NIC with & one 82543GC NIC without hardware support for TSO ETH1 ETH2 Throughput/Performance System Utilization on off 1836 24.54 % ------------------------------------------------------------------ bond-patch-2.6.1 and 82543GC NICs Test results with all HW acceleration bits on for 1 NIC and turned off for the other NIC ETH1 ETH2 Throughput/Performance System Utilization on off 1851 35 % bond-patch-2.6.2 and 82543GC NICs Test results with all HW acceleration bits on for 1 NIC and turned off for the other NIC ETH1 ETH2 Throughput/Performance System Utilization on off 1822 17 % ------------------------------------------------------------------ bond-patch-2.6.1 and 82543GC NICs Test results with all HW acceleration bits turned off for both NICs ETH1 ETH2 Throughput/Performance System Utilization off off 1816 35 % bond-patch-2.6.2 and 82543GC NICs Test results with all HW acceleration bits turned off for both NICs ETH1 ETH2 Throughput/Performance System Utilization off off 1604 16.23 % - 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/