From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [RFC PATCH] Exporting Guest RAM information for NUMA binding Date: Wed, 30 Nov 2011 17:25:15 +0100 Message-ID: <1322670315.2921.288.camel@twins> References: <20111029184502.GH11038@in.ibm.com> <7816C401-9BE5-48A9-8BA9-4CDAD1B39FC8@suse.de> <20111108173304.GA14486@sequoia.sous-sol.org> <20111121150054.GA3602@in.ibm.com> <1321889126.28118.5.camel@twins> <20111121160001.GB3602@in.ibm.com> <1321894980.28118.16.camel@twins> <4ECB0019.7020800@codemonkey.ws> <20111123150300.GH8397@redhat.com> <4ECD3CBD.7010902@suse.de> <20111130162237.GC27308@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Cc: Andrea Arcangeli , kvm list , qemu-devel Developers , Alexander Graf , Chris Wright , bharata@linux.vnet.ibm.com, Vaidyanathan S To: dipankar@in.ibm.com Return-path: In-Reply-To: <20111130162237.GC27308@in.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org On Wed, 2011-11-30 at 21:52 +0530, Dipankar Sarma wrote: >=20 > Also, if at all topology changes due to migration or host kernel decision= s, > we can make use of something like VPHN (virtual processor home node) > capability on Power systems to have guest kernel update its topology > knowledge. You can refer to that in > arch/powerpc/mm/numa.c.=20 I think that fail^Wfeature of PPC is terminally broken. You simply cannot change the topology after the fact.=20 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:36265) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RVmyg-0007q0-UY for qemu-devel@nongnu.org; Wed, 30 Nov 2011 11:25:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RVmyg-0007cA-0p for qemu-devel@nongnu.org; Wed, 30 Nov 2011 11:25:46 -0500 Received: from casper.infradead.org ([85.118.1.10]:34661) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RVmyf-0007ba-Sn for qemu-devel@nongnu.org; Wed, 30 Nov 2011 11:25:45 -0500 Message-ID: <1322670315.2921.288.camel@twins> From: Peter Zijlstra Date: Wed, 30 Nov 2011 17:25:15 +0100 In-Reply-To: <20111130162237.GC27308@in.ibm.com> References: <20111029184502.GH11038@in.ibm.com> <7816C401-9BE5-48A9-8BA9-4CDAD1B39FC8@suse.de> <20111108173304.GA14486@sequoia.sous-sol.org> <20111121150054.GA3602@in.ibm.com> <1321889126.28118.5.camel@twins> <20111121160001.GB3602@in.ibm.com> <1321894980.28118.16.camel@twins> <4ECB0019.7020800@codemonkey.ws> <20111123150300.GH8397@redhat.com> <4ECD3CBD.7010902@suse.de> <20111130162237.GC27308@in.ibm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 Subject: Re: [Qemu-devel] [RFC PATCH] Exporting Guest RAM information for NUMA binding List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dipankar@in.ibm.com Cc: Andrea Arcangeli , kvm list , qemu-devel Developers , Alexander Graf , Chris Wright , bharata@linux.vnet.ibm.com, Vaidyanathan S On Wed, 2011-11-30 at 21:52 +0530, Dipankar Sarma wrote: >=20 > Also, if at all topology changes due to migration or host kernel decision= s, > we can make use of something like VPHN (virtual processor home node) > capability on Power systems to have guest kernel update its topology > knowledge. You can refer to that in > arch/powerpc/mm/numa.c.=20 I think that fail^Wfeature of PPC is terminally broken. You simply cannot change the topology after the fact.=20