From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NrBVx-0000o5-1w for qemu-devel@nongnu.org; Mon, 15 Mar 2010 10:43:29 -0400 Received: from [199.232.76.173] (port=42944 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NrBVw-0000no-Os for qemu-devel@nongnu.org; Mon, 15 Mar 2010 10:43:28 -0400 Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1NrBVv-0002mQ-DY for qemu-devel@nongnu.org; Mon, 15 Mar 2010 10:43:28 -0400 Received: from mtagate1.de.ibm.com ([195.212.17.161]:55310) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1NrBVu-0002lq-UC for qemu-devel@nongnu.org; Mon, 15 Mar 2010 10:43:27 -0400 Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate1.de.ibm.com (8.13.1/8.13.1) with ESMTP id o2FEhKcf003752 for ; Mon, 15 Mar 2010 14:43:20 GMT Received: from d12av01.megacenter.de.ibm.com (d12av01.megacenter.de.ibm.com [9.149.165.212]) by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o2FEhKBl1519676 for ; Mon, 15 Mar 2010 15:43:20 +0100 Received: from d12av01.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av01.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id o2FEhKKf012183 for ; Mon, 15 Mar 2010 15:43:20 +0100 Date: Mon, 15 Mar 2010 07:18:12 -0700 From: Muli Ben-Yehuda Subject: Re: [Qemu-devel] Ideas wiki for GSoC 2010 Message-ID: <20100315141812.GA2790@il.ibm.com> References: <20100310183023.6632aece@redhat.com> <4B9E2745.7060903@redhat.com> <20100315125313.GK9457@il.ibm.com> <20100315130310.GE13108@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100315130310.GE13108@8bytes.org> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Joerg Roedel Cc: agraf@suse.de, aliguori@us.ibm.com, kvm@vger.kernel.org, jan.kiszka@siemens.com, qemu-devel@nongnu.org, Luiz Capitulino , Avi Kivity , agl@us.ibm.com, Nadav Amit , Ben-Ami Yassour On Mon, Mar 15, 2010 at 02:03:11PM +0100, Joerg Roedel wrote: > On Mon, Mar 15, 2010 at 05:53:13AM -0700, Muli Ben-Yehuda wrote: > > On Mon, Mar 15, 2010 at 02:25:41PM +0200, Avi Kivity wrote: > > > On 03/10/2010 11:30 PM, Luiz Capitulino wrote: > > > > > > Hi there, > > > > > > > > Our wiki page for the Summer of Code 2010 is doing quite well: > > > > > > > >http://wiki.qemu.org/Google_Summer_of_Code_2010 > > > > > > I will add another project - iommu emulation. Could be very > > > useful for doing device assignment to nested guests, which could > > > make testing a lot easier. > > > > Our experiments show that nested device assignment is pretty much > > required for I/O performance in nested scenarios. > > Really? I did a small test with virtio-blk in a nested guest (disk > read with dd, so not a real benchmark) and got a reasonable > read-performance of around 25MB/s from the disk in the l2-guest. Netperf running in L1 with direct access: ~950 Mbps throughput with 25% CPU utilization. Netperf running in L2 with virtio between L2 and L1 and direct assignment between L1 and L0: roughly the same throughput, but over 90% CPU utilization! Now extrapolate to 10GbE. Cheers, Muli