From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew de Andrade Subject: Does KVM suffer from ACK-compression as you increase the number of VMs? Date: Tue, 19 May 2009 18:22:23 -0300 Message-ID: References: <0199E0D51A61344794750DC57738F58E66BBF927A9@GVW1118EXC.americas.hpqcorp.net> <4A0A7556.4070406@redhat.com> <0199E0D51A61344794750DC57738F58E66BC980A2D@GVW1118EXC.americas.hpqcorp.net> <4A107E3A.9050209@redhat.com> Mime-Version: 1.0 (Apple Message framework v935.3) Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from cl01.mobimail.com ([201.76.62.17]:43156 "EHLO cl01.mobimail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751113AbZESVW0 (ORCPT ); Tue, 19 May 2009 17:22:26 -0400 Received: from [200.234.206.96] (account andrew.andrade@mobimail.locaweb.com.br [200.234.206.96] verified) by hm1634.cl01.mobimail.com (CommuniGate Pro SMTP 5.2.13) with ESMTPSA id 23523912 for kvm@vger.kernel.org; Tue, 19 May 2009 18:22:23 -0300 In-Reply-To: <4A107E3A.9050209@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: I recently read the following paper from 2004 that discusses ACK- compression in a VMware GSX 2.5.1 environment. http://www.cs.clemson.edu/~jmarty/papers/ccn2004.pdf I was wondering if anyone had checked to see if KVM also suffers from ACK-compression as you increase the number of VMs on each host (increasing virtualization overhead)? If it does suffer delays, what solutions exist for remedying this? In addition to that, I was also curious what the maximum number of VMs people have been able to fit on a host, and what bottlenecks they encountered as they reached a maximum level of VMs before things fell apart. thanks, andrew