From owner-freebsd-xen@FreeBSD.ORG Tue Mar 31 00:54:56 2015 Return-Path: Delivered-To: freebsd-xen@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id E0F611A0 for ; Tue, 31 Mar 2015 00:54:55 +0000 (UTC) Received: from os-mail-4.tamu.edu (os-mail-4.tamu.edu [165.91.23.218]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "smtp-relay.tamu.edu", Issuer "InCommon RSA Server CA" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AE8AF392 for ; Tue, 31 Mar 2015 00:54:55 +0000 (UTC) X-TAMU-Auth-ID: None X-TAMU-SenderIP: 165.91.22.240 Received: from exchange.tamu.edu (exch-2p-snat-pool.tamu.edu [165.91.22.240]) by os-mail-4.itio.tamu.edu (8.14.7/8.14.7) with ESMTP id t2UNqH34041346 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Mon, 30 Mar 2015 18:52:17 -0500 Received: from MB03.ads.tamu.edu ([169.254.3.105]) by caex01.ads.tamu.edu ([128.194.147.20]) with mapi id 14.03.0195.001; Mon, 30 Mar 2015 18:52:16 -0500 From: Andrew Daugherity To: =?Windows-1252?Q?Roger_Pau_Monn=E9?= Subject: Re: Poor performance with FreeBSD 10.1 under Xen 4.2 Thread-Topic: Poor performance with FreeBSD 10.1 under Xen 4.2 Thread-Index: AQHQaOOfinlni718o0SDQUrW328qGJ0yNL4AgAPWZYA= Date: Mon, 30 Mar 2015 23:52:16 +0000 Message-ID: <57429F3F-8CC9-4C4F-86DF-3E63C5853B01@tamu.edu> References: <115BE54D-078A-4C45-8904-861DAB316C03@tamu.edu> <5516A998.10206@citrix.com> In-Reply-To: <5516A998.10206@citrix.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [128.194.89.247] Content-Type: text/plain; charset="Windows-1252" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.13.68, 1.0.33, 0.0.0000 definitions=2015-03-30_04:2015-03-30,2015-03-30,1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 kscore.is_bulkscore=4.95264940170159e-12 kscore.compositescore=0 circleOfTrustscore=0 compositescore=0.999586866343301 suspectscore=0 recipient_domain_to_sender_totalscore=0 phishscore=0 bulkscore=0 kscore.is_spamscore=0 rbsscore=0.999586866343301 recipient_to_sender_totalscore=0 recipient_domain_to_sender_domain_totalscore=0 spamscore=0 recipient_to_sender_domain_totalscore=0 urlsuspectscore=0.999586866343301 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=7.0.1-1402240000 definitions=main-1503300212 Cc: "freebsd-xen@freebsd.org" X-BeenThere: freebsd-xen@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussion of the freebsd port to xen - implementation and usage List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 Mar 2015 00:54:56 -0000 > On Mar 28, 2015, at 8:16 AM, Roger Pau Monn=E9 wro= te: >=20 > Hello, >=20 > Thanks for the detailed description of the issue. I've reproduced your > benchmarks and with the hardware I've used (Core i3-5010U) I'm not able > to see this performance issue, below are the figures in my case: > [...] >=20 > I'm Ccing feld because IIRC he found something similar on one of his > boxes, that also had VTx but no EPT (just like yours). Would it be > possible for you to try the same set of tests on a different hardware? I think you're on to something. I copied this FreeBSD 10.1 VM to a system = running the same version of Xen (and same SLES in the Dom0), but with an Op= teron 2360SE CPU (which has both SVM and NPT), and it is *much* faster (and= feels more responsive too): Forked, executed and destroyed 5000 processes in 5.216613 seconds. [Subsequent runs are consistently between 5.1 and 5.5 seconds.] sssd configure: 22.210u 8.751s 0:30.39 101.8% 4915+236k 0+300io 31pf+0w sssd build: 176.556u 78.846s 2:15.77 188.1% 5534+217k 49+44io 8pf+0w I'll run some more benchmarks, but I don't recall Linux VMs being noticeabl= y different in speed between the Opteron and the Xeon systems -- I'm pretty= sure it's not a case of a raw CPU power advantage. > Also, if even FreeBSD 10.1 compiled without XENHVM shows this issue it > means there's something in the generic code that doesn't work well when > running virtualized on this specific hardware, but I'm afraid figuring > it out is not trivial. One place to start would be asking on > freebsd-hackers and freebsd-virt. I suppose this performance delta with presence of EPT/NPT vs. lack thereof = means it's time to take it to those lists? My next step will be to test 10= .1 under KVM on the Xeon to confirm whether it's a Xen issue or strictly EP= T. Thanks for the tips! -Andrew