From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: [PATCH 1/2] libxl: turn NUMA placement misconfigs into warnings Date: Fri, 3 Jul 2015 16:52:01 +0200 Message-ID: <1435935121.14347.88.camel@citrix.com> References: <20150701135059.15951.39938.stgit@Solace.station> <20150701140306.15951.83934.stgit@Solace.station> <21907.64386.480660.370761@mariner.uk.xensource.com> <1435919723.9447.72.camel@citrix.com> <21910.27981.264095.978895@mariner.uk.xensource.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============3937306767028675684==" Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ZB2KY-0004qX-7t for xen-devel@lists.xenproject.org; Fri, 03 Jul 2015 14:52:42 +0000 In-Reply-To: <21910.27981.264095.978895@mariner.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: Ian Jackson Cc: xen-devel@lists.xenproject.org, Wei Liu , Ian Campbell , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org --===============3937306767028675684== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-2vhB4zNPU6oqWAJnmo6g" --=-2vhB4zNPU6oqWAJnmo6g Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2015-07-03 at 12:09 +0100, Ian Jackson wrote: > Ian Campbell writes ("Re: [PATCH 1/2] libxl: turn NUMA placement misconfi= gs into warnings"): > > On Wed, 2015-07-01 at 15:38 +0100, Ian Jackson wrote: > > > But, be aware that you are making a semantic change to the API which > > > cannot be reverted for backwards-compatibility reasons. > >=20 > > Is any further action required due to this? >=20 > Not if it doesn't cause you or Dario to change your mind about the > patch :-). >=20 It doesn't. This is the right thing to do, and should have been like this from the beginning! Just FTR, the reason why we were using the numa_autoplacement for sanity checking was that, a while back, we were always passing a (potentially) valid cpumap (for vcpu affinity) as part of the domain config. Hence we needed something to distinguish the case were such a cpumap was full (or empty, I can't recall) because of an explicit user choice, or as a mean to ask libxl to perform the automatic placement. I can't remember either why we did not do it, in the first place, the way it is now (i.e., cpumaps *not allocated* --> do the placement), but I never liked the fact that, if one[*] sets the affinity explicitly, but forget to set numa_autoplacement to false, the domain does not build. So, in summary, no, I don't think I will easily change my mind about this needing to be a warning, rather than a fatal error. Thanks and Regards, Dario [*] of course I'm talking about downstream toolstacks, like xl or libvirt, not actual users, as in xl we do this consistently! --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-2vhB4zNPU6oqWAJnmo6g 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 iEYEABECAAYFAlWWoZkACgkQk4XaBE3IOsSEJQCZAcCjvRGB2K6/FOhDgGMEEjuD gVIAn197mjBJhpBNLnI97TaqT8k1ATL6 =ci9Z -----END PGP SIGNATURE----- --=-2vhB4zNPU6oqWAJnmo6g-- --===============3937306767028675684== 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 --===============3937306767028675684==--