From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: Fwd: Question about the status of vNUMA in Xen Date: Tue, 15 Sep 2015 17:49:53 +0200 Message-ID: <1442332193.7789.11.camel@citrix.com> References: <20150907102347.GD6436@zion.uk.xensource.com> <20150908095037.GE11097@zion.uk.xensource.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============2399094222801304262==" Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ZbsUZ-0007wC-68 for xen-devel@lists.xenproject.org; Tue, 15 Sep 2015 15:49:59 +0000 In-Reply-To: <20150908095037.GE11097@zion.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Wei Liu Cc: "xen-devel@lists.xenproject.org" , =?UTF-8?Q?=E7=94=98=E6=B8=85=E7=94=9C?= List-Id: xen-devel@lists.xenproject.org --===============2399094222801304262== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-Y8ZjDrhYMOxPNMfpJAU/" --=-Y8ZjDrhYMOxPNMfpJAU/ Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2015-09-08 at 10:50 +0100, Wei Liu wrote: > On Tue, Sep 08, 2015 at 01:21:04AM +0000, =E7=94=98=E6=B8=85=E7=94=9C wro= te: > > > So far, I have read the Xen NUMA Roadmap page and watched the > > > video about vNUMA in Xen on Youtube. I have known that some work > > > has been done for vNUMA in Xen. Since my benchmark result show a > > > great improvement in Xen-4.5.1 when compared with Xen-4.0.1. I'm > > > puzzled if vNUMA has contributed to that improvement. > >=20 > > No. That's mostly due to other improvements. > >=20 > > Wei. > > I=E2=80=99m sorry that I didn=E2=80=99t express clearly in the last mai= l. What I want to > > know is > >=20 > > that how much the NUMA optimizations (including NUMA-aware VM placement= , > >=20 > > NUMA-aware scheduling and vNUMA) contribute to the improvement > >=20 >=20 Going from 4.0 to 4.5, you get automatic placement and NUMA aware scheduling, not to mention that many other improvements happened in between those two release, even if they may not look NUMA-related at a first glance, may well be leading to better performance. The NUMA roadmap page is slightly outdated, and I commit to update it ASAP. Anyway, if you want to isolate the contribution of each single feature, you can configure things in such a way that you 'temporarily disable' them. For instance, you can use vcpu pinning di tweak/disable automatic placement, and check how the numbers change. For tweaking/disabling NUMA aware scheduling, you should play with hard and soft affinity (i.e., some more refined ways of doing pinning, check what `xl vcpu-pin' does these days). Regards, Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-Y8ZjDrhYMOxPNMfpJAU/ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEABECAAYFAlX4PiEACgkQk4XaBE3IOsTUegCfTaWyFY0VyZJiH6h31BAKIpL/ 1wcAn3y7nHM/JRvFMNdoIhgKC9XzPbO0 =IIIj -----END PGP SIGNATURE----- --=-Y8ZjDrhYMOxPNMfpJAU/-- --===============2399094222801304262== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel --===============2399094222801304262==--