From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DC8DC10DCE for ; Sun, 15 Mar 2020 14:45:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 373F8206B1 for ; Sun, 15 Mar 2020 14:45:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 373F8206B1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C3D246B0003; Sun, 15 Mar 2020 10:45:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BEE266B0006; Sun, 15 Mar 2020 10:45:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B03BA6B0007; Sun, 15 Mar 2020 10:45:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0023.hostedemail.com [216.40.44.23]) by kanga.kvack.org (Postfix) with ESMTP id 96DA16B0003 for ; Sun, 15 Mar 2020 10:45:57 -0400 (EDT) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 9AE0A52B2 for ; Sun, 15 Mar 2020 14:45:57 +0000 (UTC) X-FDA: 76597871154.19.hot49_dc568df0619 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin19.hostedemail.com (Postfix) with ESMTP id 1DDC1389CD for ; Sun, 15 Mar 2020 14:20:06 +0000 (UTC) X-HE-Tag: hot49_dc568df0619 X-Filterd-Recvd-Size: 1919 Received: from gentwo.org (gentwo.org [3.19.106.255]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Sun, 15 Mar 2020 14:20:05 +0000 (UTC) Received: by gentwo.org (Postfix, from userid 1002) id 1BDDF3F7A9; Sun, 15 Mar 2020 14:20:05 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by gentwo.org (Postfix) with ESMTP id 19C4C3F6EC; Sun, 15 Mar 2020 14:20:05 +0000 (UTC) Date: Sun, 15 Mar 2020 14:20:05 +0000 (UTC) From: Christopher Lameter X-X-Sender: cl@www.lameter.com To: Srikar Dronamraju cc: Andrew Morton , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Mel Gorman , Vlastimil Babka , "Kirill A. Shutemov" , Linus Torvalds Subject: Re: [PATCH 3/3] mm/page_alloc: Keep memoryless cpuless node 0 offline In-Reply-To: <20200311110237.5731-4-srikar@linux.vnet.ibm.com> Message-ID: References: <20200311110237.5731-1-srikar@linux.vnet.ibm.com> <20200311110237.5731-4-srikar@linux.vnet.ibm.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 11 Mar 2020, Srikar Dronamraju wrote: > Currently Linux kernel with CONFIG_NUMA on a system with multiple > possible nodes, marks node 0 as online at boot. However in practice, > there are systems which have node 0 as memoryless and cpuless. Would it not be better and simpler to require that node 0 always has memory (and processors)? A mininum operational set? We can dynamically number the nodes right? So just make sure that the firmware properly creates memory on node 0?