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Date:   Sun, 15 Mar 2020 14:20:05 +0000 (UTC)
From:   Christopher Lameter <cl@linux.com>
To:     Srikar Dronamraju <srikar@linux.vnet.ibm.com>
cc:     Andrew Morton <akpm@linux-foundation.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Michal Hocko <mhocko@suse.com>,
        Mel Gorman <mgorman@suse.de>, Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 3/3] mm/page_alloc: Keep memoryless cpuless node 0
 offline
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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?