From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: [Hackathon minutes] PV frontends/backends and NUMA machines Date: Tue, 21 May 2013 12:03:20 +0200 Message-ID: <1369130600.12423.30.camel@Solace> References: <20130521083251.GD9626@ocelot.phlegethon.org> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============6235076615898664556==" Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: George Dunlap Cc: "xen-devel@lists.xensource.com" , Tim Deegan , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org --===============6235076615898664556== Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-28QSAk7+NXLtr2CeHuUE" --=-28QSAk7+NXLtr2CeHuUE Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On mar, 2013-05-21 at 09:49 +0100, George Dunlap wrote: > On Tue, May 21, 2013 at 9:47 AM, George Dunlap > > There are two aspects of this. First would be, if dom0.nvcpus < > > host.npcpus, to place the vcpus reasonably on the various numa nodes. >=20 > And indeed, if dom0.nvcpus < host.nnodes, to try to minimize the > distance from the vcpus to all nodes on the system. >=20 Yep, we definitely want that too. I have patches for the toolstack counterpart of this (when speaking about DomUs), but I was using a quadratic (in the number of nodes) algorithm, and we need to find something better to scan and make decisions out of the distances matrix, and that is especially true if we're in Xen rather than in libxl I guess. :-P Also, IONUMA machines can possibly introduce additional constraints: for instance, you almost likely want a vCPU on all the nodes that have an IO controller attached! Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-28QSAk7+NXLtr2CeHuUE 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 v1.4.13 (GNU/Linux) iEYEABECAAYFAlGbRmgACgkQk4XaBE3IOsRRWACfUaS4+eWzPADEbEH4e+UwGr35 7S4An12MiDfdwz0iRdYct0UQydzfxORa =uGUb -----END PGP SIGNATURE----- --=-28QSAk7+NXLtr2CeHuUE-- --===============6235076615898664556== 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 --===============6235076615898664556==--