From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srivatsa Vaddagiri Subject: Re: vCPU scalability for linux VMs Date: Thu, 6 May 2010 11:23:55 +0530 Message-ID: <20100506055355.GB6251@linux.vnet.ibm.com> References: <1815416666.20100504184534@istomin.de> <20100505172739.GB23892@linux.vnet.ibm.com> <1085378510.20100505123111@istomin.de> Reply-To: vatsa@in.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "kvm@vger.kernel.org" To: Alec Istomin Return-path: Received: from e39.co.us.ibm.com ([32.97.110.160]:38530 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751136Ab0EFFx6 (ORCPT ); Thu, 6 May 2010 01:53:58 -0400 Received: from d03relay01.boulder.ibm.com (d03relay01.boulder.ibm.com [9.17.195.226]) by e39.co.us.ibm.com (8.14.3/8.13.1) with ESMTP id o465jNVA016987 for ; Wed, 5 May 2010 23:45:23 -0600 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay01.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o465rvZJ163662 for ; Wed, 5 May 2010 23:53:57 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o465rubM020370 for ; Wed, 5 May 2010 23:53:57 -0600 Content-Disposition: inline In-Reply-To: <1085378510.20100505123111@istomin.de> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, May 05, 2010 at 12:31:11PM -0700, Alec Istomin wrote: > > On Wednesday, May 5, 2010 at 13:27:39 -0400, Srivatsa Vaddagiri wrote: > >> My preliminary results show that single vCPU Linux VMs perform up to 10 > >> times better than 4vCPU Linux VMs (consolidated performance of 8 VMs on > >> 8 core pre-Nehalem server). I suspect that I'm missing something major > >> and look for any means that can help improve SMP VMs performance. > > > Could you provide more details of what workload was used to compare this > > performance? > > It's Dell's DVD-Store LAMP stack test suite with Medium database (about > 1 GB MySQL data) . 8x 2Gb VMs (on 16GB RAM host) with different vCPU > configuration simultaneously loaded by external web clients. Ok ..Do you have any more data on how the vCPU scalability looks like (how the throughput scales with increasing vCPUs)? - vatsa