Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757647AbXFZPwq (ORCPT ); Tue, 26 Jun 2007 11:52:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754138AbXFZPwh (ORCPT ); Tue, 26 Jun 2007 11:52:37 -0400 Received: from mga09.intel.com ([134.134.136.24]:37175 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754748AbXFZPwh (ORCPT ); Tue, 26 Jun 2007 11:52:37 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.16,464,1175497200"; d="scan'208";a="100296018" Date: Tue, 26 Jun 2007 08:48:04 -0700 From: "Keshavamurthy, Anil S" To: Muli Ben-Yehuda Cc: Arjan van de Ven , Andi Kleen , Andrew Morton , "Keshavamurthy, Anil S" , linux-kernel@vger.kernel.org, gregkh@suse.de, suresh.b.siddha@intel.com, ashok.raj@intel.com, davem@davemloft.net, clameter@sgi.com Subject: Re: [Intel IOMMU 00/10] Intel IOMMU support, take #2 Message-ID: <20070626154803.GA3374@linux-os.sc.intel.com> Reply-To: "Keshavamurthy, Anil S" References: <20070619213701.219910000@askeshav-devel.jf.intel.com> <20070625234550.058635cb.akpm@linux-foundation.org> <200706260912.45838.ak@suse.de> <20070626111324.GB4320@rhun.ibm.com> <46812ADF.3060609@linux.intel.com> <20070626151125.GD8274@rhun.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070626151125.GD8274@rhun.ibm.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1299 Lines: 28 On Tue, Jun 26, 2007 at 11:11:25AM -0400, Muli Ben-Yehuda wrote: > On Tue, Jun 26, 2007 at 08:03:59AM -0700, Arjan van de Ven wrote: > > Muli Ben-Yehuda wrote: > > >How much? we have numbers (to be presented at OLS later this week) > > >that show that on bare-metal an IOMMU can cost as much as 15%-30% more > > >CPU utilization for an IO intensive workload (netperf). It will be > > >interesting to see comparable numbers for VT-d. > > > > for VT-d it is a LOT less. I'll let anil give you his data :) > > Looking forward to it. Note that this is on a large SMP machine with > Gigabit ethernet, with netperf TCP stream. Comparing numbers for other > benchmarks on other machines is ... less than useful, but the numbers > themeselves are interesting. Our initial benchmark results showed we had around 3% extra CPU utilization overhead when compared to native(i.e without IOMMU). Again, our benchmark was on small SMP machine and we used iperf and a 1G ethernet cards. Going forward we will do more benchmark tests and will share the results. -Anil - 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/