From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39683) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e5M0x-0001AB-TO for qemu-devel@nongnu.org; Thu, 19 Oct 2017 21:22:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e5M0w-00051y-U9 for qemu-devel@nongnu.org; Thu, 19 Oct 2017 21:22:19 -0400 Received: from ozlabs.org ([2401:3900:2:1::2]:48301) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e5M0w-0004zw-IS for qemu-devel@nongnu.org; Thu, 19 Oct 2017 21:22:18 -0400 Date: Fri, 20 Oct 2017 12:21:30 +1100 From: David Gibson Message-ID: <20171020012130.GG13245@umbus> References: <1508170976-96869-1-git-send-email-imammedo@redhat.com> <20171016163636.GI11975@redhat.com> <20171017092702.5b82103b@nial.brq.redhat.com> <20171017150759.GB31897@redhat.com> <20171017180635.6a900616@nial.brq.redhat.com> <20171018153010.GL9719@redhat.com> <20171018202240.GD2942@localhost.localdomain> <20171019114954.GC13245@umbus> <58846850-bbe2-e1c4-2235-58b3f6709ba6@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="UTZ8bGhNySVQ9LYl" Content-Disposition: inline In-Reply-To: <58846850-bbe2-e1c4-2235-58b3f6709ba6@redhat.com> Subject: Re: [Qemu-devel] [RFC 0/6] enable numa configuration before machine_init() from HMP/QMP List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Eduardo Habkost , "Daniel P. Berrange" , Igor Mammedov , peter.maydell@linaro.org, pkrempa@redhat.com, cohuck@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com --UTZ8bGhNySVQ9LYl Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Oct 19, 2017 at 02:23:04PM +0200, Paolo Bonzini wrote: > On 19/10/2017 13:49, David Gibson wrote: > > Note that describing socket/core/thread tuples as arch independent (or > > even machine independent) is.. debatable. I mean it's flexible enough > > that most platforms can be fit to that scheme without too much > > straining. But, there's no arch independent way of defining what each > > level means in terms of its properties. > >=20 > > So, for example, on spapr - being paravirt - there's no real > > distinction between cores and sockets, how you divide them up is > > completely arbitrary. >=20 > Same on x86, actually. >=20 > It's _common_ that cores on the same socket share L3 cache and that a > socket spans an integer number of NUMA nodes, but it doesn't have to be > that way. >=20 > QEMU currently enforces the former (if it tells the guest at all that > there is an L3 cache), but not the latter. Ok. Correct me if I'm wrong, but doesn't ACPI describe the NUMA architecture in terms of this thread/core/socket heirarchy? That's not true for PAPR, where the NUMA topology is described in an independent set of (potentially arbitrarily nested) nodes. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --UTZ8bGhNySVQ9LYl Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAlnpT5oACgkQbDjKyiDZ s5IKRhAAvRd8XlNBed63GzKSYXZUgKrHPxpyI7xQMmc36zAkXE4gXsaaQNsr37pl m5ADtv+nfjU9Gkv344VQfim2Fb7+UoeTQOCnSZC1gX2mu1A5O3uXPaiNYE4JaBd5 uJf4vE8kFziBDUVPkXYCZEEuFdKMPRo3i3YHSTESvrpBSrSPzfXVYs5g94EaRJ7L HC4Ft3KNe2SM3FYhS1BGGUmTc7LbM5No2Ofg8boI8wdNnsD4A5wrKqYr3opvjkXH Lx+iNuimDSnbFzH0DB/dy4SsbypwifqhyEfy3+SOwOQ9qBjDSLCIZkNL87y5Av1A MRLSkAv7rYxLu1PEyg+CTGNbGFq+99/JC+GDe2rwZfnK6731s8aIZpyOVZ0uPRG5 xcfv6zSIm28WySMJEFUhyKbfTkmlwWCd4V7y+mhraXqqDNkhI8rL5UlXuOT1a5JL J1PncA3vnpRfyCa/Pfo1aQqXwcxdW2Nm/hM/R893EsJcTkgGqThl5VVVC7uG74d1 lPEaZ1c7MsZGgv6wvL2WyYKBvcOlpWbp+K84hNRl4TYdAPWZ+XYnE/rBmLTQofV5 jS+iqFtliZJIi3/V6dqIbTrElRC3pQxIiQjnXYRxuTizM04i0ySg57RCA25b1400 U+FSKfxFkqPS84cnFZUiqYkng2t38u3J73zEAhkUZuGfkcdZkU4= =AFx1 -----END PGP SIGNATURE----- --UTZ8bGhNySVQ9LYl--