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Date: Mon, 16 Oct 2017 11:02:24 -0500 (CDT)
From: Christopher Lameter <cl@linux.com>
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To: Michal Hocko <mhocko@kernel.org>
cc: Pavel Machek <pavel@ucw.cz>, Mike Kravetz <mike.kravetz@oracle.com>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
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        Anshuman Khandual <khandual@linux.vnet.ibm.com>,
        Laura Abbott <labbott@redhat.com>, Vlastimil Babka <vbabka@suse.cz>
Subject: Re: [RFC PATCH 3/3] mm/map_contig: Add mmap(MAP_CONTIG) support
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On Mon, 16 Oct 2017, Michal Hocko wrote:

> > So I mmap(MAP_CONTIG) 1GB working of working memory, prefer some data
> > structures there, maybe recieve from network, then decide to write
> > some and not write some other.
>
> Why would you want this?

Because we are receiving a 1GB block of data and then wan to write it to
disk. Maybe we want to modify things a bit and may not write all that we
received.