From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Jackson Subject: Re: Qemu v1.7.1 & CentOS 6.4 Date: Fri, 28 Mar 2014 22:45:16 -0500 Message-ID: <533641CC.2080902@theiggy.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: Lane Eckley , kvm@vger.kernel.org Return-path: Received: from theiggy.com ([66.220.1.110]:51721 "EHLO mail.theiggy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750925AbaC2DxM (ORCPT ); Fri, 28 Mar 2014 23:53:12 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 03/28/2014 03:55 PM, Lane Eckley wrote: > Hi Everyone, > > I am running into performance issues with Windows guest VM's in > conjunction with the rather old version of Qemu-KVM that is currently > being shipped with rhel 6.4 and as such I am looking to upgrade to the > latest stable release of qemu (v1.7.1 if I am not mistaken). > > As it stands now I have been unsuccessful in locating a good > guide/tutorial on how to correctly update (or remove & install) v1.7.1 > - Does anyone have a good tutorial on how to properly get it installed > under CentOS 6 (or rhel 6 in general)? > > The reason for the upgrade is due high context switch rate when the > Windows virtual VM's are idle causing the hypervisor machine to > utilize a lot more CPU than it should be. Based on my Google skills I > have located several threads noting upgrade to at least 0.12.4 should > help resolve the issue, however as it stands right now I really do not > have any confirmation of this. RedHat very likely has backported any fixes and probably most performance improvements from 0.12-1.7. I'd suggest upgrading to the latest RHEL release and try to enable the hv-* options (hv-spinlocks, hv-relaxed, hv-vapic, hv-time or whatever is supported by RHEL's kvm). IIRC, there is also a document/page in the RHEL docs that talks specifically about Windows guest performance. > > As to CentOS, unfortunately the control panel system we are using > currently limits us to rhel 6 based distros and as such swapping to a > debian based distro or otherwise is not currently an option. > > Any advice & feedback would be very much appreciated. > > Thanks! > > -Lane > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html