From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Tippett Subject: Re: sync guest calls made async on host - SQLite performance Date: Wed, 07 Oct 2009 12:53:53 -0400 Message-ID: <4ACCC7A1.9060303@gmail.com> References: <4ABC6AA5.6080909@tauceti.net> <4ABF4E95.5070100@redhat.com> <4ABF5596.9050207@gmail.com> <4AC259DC.2080807@codemonkey.ws> <4AC260BB.3090906@gmail.com> <4AC27355.3090303@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Avi Kivity , RW , kvm@vger.kernel.org, dustin.kirkland@canonical.com To: Anthony Liguori Return-path: Received: from mail-fx0-f227.google.com ([209.85.220.227]:54834 "EHLO mail-fx0-f227.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759606AbZJGRBq (ORCPT ); Wed, 7 Oct 2009 13:01:46 -0400 Received: by fxm27 with SMTP id 27so4807849fxm.17 for ; Wed, 07 Oct 2009 10:01:09 -0700 (PDT) In-Reply-To: <4AC27355.3090303@codemonkey.ws> Sender: kvm-owner@vger.kernel.org List-ID: (Resending to the list without multi-part). I now have more information. Dustin, The version used was 0.11.0-rc2, from the 2009-09-11 karmic daily build. The VM identifies itself as "AMD QEMU Virtual CPU version 0.10.92 stepping 03". When you indicated that you had attempted to reproduce the problem, what mechanism did you use? Was it Karmic + KVM as the host and Karmic as the guest? What test did you use? I will re-open the launchpad bug if you believe it makes sense to continue the discussions there. Anthony, If you can suspend your disbelief for a short while and ask questions to clarify the details. My only interest here is to understand the results presented by the benchmark and determine if there are data integrity risks. Fundamentally, if there are modes of operation that applications can get a considerable performance boost by running the same OS under KVM then there will be lots of people happy. But realistically it is an indication of something wrong, misconfigured or just broken it bears at least some discussion. Bear in mind that upstream is relevant for KVM, but for distributions shipping KVM, they may have secondary concerns about patchesets and upstream changes that may be relevant for how they support their customers. Regards, Matthew -------- Original Message -------- Subject: Re: sync guest calls made async on host - SQLite performance From: Anthony Liguori To: Matthew Tippett Cc: Avi Kivity , RW , kvm@vger.kernel.org Date: 09/29/2009 04:51 PM > Matthew Tippett wrote: > > Your confidence is misplaced apparently. > >> and I have pieced together the following information. I should be >> able to get the actual daily build number but broadly it looks like it >> was >> >> Ubuntu 9.10 daily snapshot (~ 9th - 21st September) >> Linux 2.6.31 (packaged as 2.6.31-10.30 to 2.6.31-10.32) >> qemu-kvm 0.11 (packaged as 0.11.0~rc2-0ubuntu to 0.11.0~rc2-0ubuntu5 > > That's extremely unlikely. > >> But, if it turned out to be Ubuntu 9.10, linux 2.6.31, qemu-kvm 0.11 >> would there be any concerns? > > It's not relevant because it's not qemu-kvm-0.11.