From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gianluca Guida Subject: Re: Re: Poor performance on HVM (kernbench) Date: Thu, 11 Sep 2008 11:00:40 +0100 Message-ID: <48C8EC48.6080507@eu.citrix.com> References: <1e16a9ed0809101123m71a12030v7d06501f6467f93@mail.gmail.com> <1e16a9ed0809101422p6a58304dxaa1a92847109a518@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1e16a9ed0809101422p6a58304dxaa1a92847109a518@mail.gmail.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: deshantm@gmail.com Cc: Muli Ben-Yehuda , Anthony Liguori , xen-devel mailing list List-Id: xen-devel@lists.xenproject.org Todd Deshane wrote: > Xen 3.3 should be an improvement with shadow3 right? As other people already said, shadow3 (especially the current unsync policy) was mostly developed with Windows performance in mind. I would be surprised if the shadow algorithm is causing such a performance loss though; but in any case, you can disable the out-of-sync feature by removing SHOPT_OUT_OF_SYNC from SHADOW_OPTIMIZATIONS in xen/arch/x86/mm/shadows/private.h (setting it to 0xff instead of 0x1ff), reverting the shadow code back to shadow 2 again. Can you please test that and see if it makes any difference? Thanks, Gianluca > > Should I need to adjust the shadow_memory parameter for the guest? > > I'm going to try Xen 3.2.1 from source next. > > Todd > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel