From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56645) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z5kav-0000xR-B8 for qemu-devel@nongnu.org; Thu, 18 Jun 2015 20:55:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z5kap-0006LS-Rk for qemu-devel@nongnu.org; Thu, 18 Jun 2015 20:55:45 -0400 Received: from mproxyhzb1.163.com ([123.58.178.201]:36289) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z5kap-0006Gr-8M for qemu-devel@nongnu.org; Thu, 18 Jun 2015 20:55:39 -0400 Date: Fri, 19 Jun 2015 08:40:11 +0800 (CST) From: cauchy-love In-Reply-To: <20150616130539.GC29405@stefanha-thinkpad.redhat.com> References: <7c4c87b8.111fa.14df75bb798.Coremail.cauchy-love@163.com> <20150616130539.GC29405@stefanha-thinkpad.redhat.com> Content-Transfer-Encoding: base64 Content-Type: text/plain; charset=gbk MIME-Version: 1.0 Message-ID: <6bc2d8e.1e4b.14e0942385e.Coremail.cauchy-love@163.com> Subject: Re: [Qemu-devel] Greate difference of disk I/O performance for guest on Qemu-2.30 of CentOS. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: qemu-devel@nongnu.org CnRoZSBpb3pvbmUgIGNvbW1hbmQgbGluZSBpczoKLi9pb3pvbmUgLWkgMCAtaSAxIC1mIC4vaW90 bXAgLVJhYiAuL2lvdG1wLnhscyAtZyA4RyAtbiA0RyAtYwoKVGhlIHByb2JsZW0gaXMgd2h5IHRo ZSBwZXJmb3JtYW5jZSBkaWZmZXJlbmNlIGlzIHNvIGJpZyBmb3IgZGlmZmVyZW50IGxpbnV4IGtl cm5lbHMuIFRoZSBndWVzdCdzIGlvIHBlcmZvcm1hbmNlIHRlc3QgaXMgYnkgYm90aCBGVFAgdG9v bHMgYW5kIHJhdyB3cml0ZSwgd2hpY2ggZGVtb25zdHJhdGUgdGhlIG11Y2ggbG93ZXIgcGVyZm9y bWFuY2Ugb2YgIENlbnRvcyA3ICgxLzEwIG9mIHRoYXQgb24gQ2VudG9zIDYuNSkuIEFuZCBob3cg Y2FuIEkgZGVidWcgdGhpcyBwcm9ibGVtPwogClRoYW5rcyBhZ2FpbiBmb3IgeW91ciBoZWxwLgoK WWkKCgoKLS0Kt6LX1M7StcTN+NLX08rP5MrWu/rWx8TcsOYKCgrU2iAyMDE1LTA2LTE2IDIxOjA1 OjM5o6wiU3RlZmFuIEhham5vY3ppIiA8c3RlZmFuaGFAZ21haWwuY29tPiDQtLXAo7oKPk9uIE1v biwgSnVuIDE1LCAyMDE1IGF0IDA5OjE0OjUyUE0gKzA4MDAsIGNhdWNoeS1sb3ZlIHdyb3RlOgo+ PiAgICBJIGFtIHJ1bm5pbmcgYSBlbWJlZGRlZCBPUyBvbiBRZW11LTIuMy4wLiBIb3dldmVyIEkg Zm91bmQgdGhhdCB0aGUgSS9PIHBlcmZvcm1hbmNlIHdhcyBxdWl0ZSBkaWZmZXJlbnQgZm9yIGRp ZmZlcmVudCBDZW50T1MgcmVsZWFzZSAoQ2VudE9TIDYuNSBhbmQgQ2VudE9TIDcuMCkuIFRoZSBD ZW50T1MgNi41IHVzZXMgbGludXgtMi42LjMyIHdoaWxlIHRoZSBDZW50T1MgNy4wIHVzZXMgbGlu dXgtMy4xMC4wLiBUaGUgSS9PIHRocm91Z2hwdXQgKHdyaXRlKSBvZiB0aGUgZm9ybWVyIChDZW50 T1MgNi41KSBpcyBhYm91dCB0ZW4gdGltZXMgb2YgdGhhdCBvbiB0aGUgbGF0dGVyIChDZW50T1Mg Ny4wKS4gQWxsIGNvbmZpZ3VyYXRpb25zIGFyZSB0aGUgc2FtZSBleGNlcHQgdGhlIGtlcm5lbCB2 ZXJzaW9uLiBBbmQgdGhlIGNvbW1hbmQgbGluZSBpcyBhcyBmb2xsb3dpbmc6Cj4+ICAgICAgICAg ICAgICAgICAgICAgICAjIHFlbXUta3ZtIC1tIDJHIC1zbXAgNCAtZW5hYmxlLWt2bSAtaGRhIGd1 ZXN0LmltZyAuLi4KPj4gIFRoZSBJL08gdGhyb3VnaHB1dCBvZiB0aGUgaG9zdCBpcyBhbG1vc3Qg dGhlIHNhbWUgZm9yIHRoZXNlIHR3byBkaWZmZXJlbnQga2VybmVscywgYXMgdGVzdGVkIGJ5IElv em9uZSB0b29sLiBBY3R1YWxseSwgSSBmb3VuZCB0aGF0IHRoZSBJTyB0aHJvdWdocHV0IGRlZ3Jh ZGVkIHNpZ25pZmljYW50bHkgc2luY2UgdGhlIDMuNCBvciBsYXRlciBrZXJuZWwgdmVyc2lvbi4g SSBhbHNvIHRyaWVkIGRpZmZlcmVudCBxZW11IHZlcnNpb25zIHN1Y2ggYXMgcWVtdS0xLjUuMywg cWVtdS0yLjEuMyBidXQgZ290IG5vIGltcHJvdmVtZW50cy4KPgo+UGxlYXNlIHBvc3QgdGhlIGlv em9uZSBjb21tYW5kLWxpbmUgeW91IGFyZSB1c2luZyBhbmQgdGhlIG91dHB1dC4KPgo+WW91ciBR RU1VIGNvbW1hbmQtbGluZSB1c2VzIHRoZSBJREUgc3RvcmFnZSBjb250cm9sbGVyLCB3aGljaCBp cyBub3QKPm9wdGltaXplZCBmb3IgcGVyZm9ybWFuY2UuICBVc3VhbGx5IHZpcnRpby1ibGsgaXMg dXNlZCB3aGVuIGdvb2QKPnBlcmZvcm1hbmNlIGlzIHJlcXVpcmVkOgo+Cj4gIC1kcml2ZSBpZj12 aXJ0aW8sY2FjaGU9bm9uZSxmb3JtYXQ9cmF3LGFpbz1uYXRpdmUsZmlsZT1ndWVzdC5pbWcKPgo+ VGhlIGd1ZXN0IE9TIG5lZWRzIHZpcnRpby1ibGsgZGV2aWNlIGRyaXZlcnMgaW4gb3JkZXIgZm9y IHRoaXMgdG8gd29yay4KPgo+U3RlZmFu