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Date: Wed, 31 May 2017 14:05:56 +0200
From: Michal Hocko <mhocko@kernel.org>
To: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
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Subject: Re: [PATCH] mm: introduce MADV_CLR_HUGEPAGE
Message-ID: <20170531120533.GK27783@dhcp22.suse.cz>
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On Wed 31-05-17 12:08:45, Mike Rapoport wrote:
> On Tue, May 30, 2017 at 12:39:30PM +0200, Michal Hocko wrote:
[...]
> > Also do you expect somebody else would use new madvise? What would be the
> > usecase?
> 
> I can think of an application that wants to keep 4K pages to save physical
> memory for certain phase, e.g. until these pages are populated with very
> few data. After the memory usage increases, the application may wish to
> stop preventing khugepged from merging these pages, but it does not have
> strong inclination to force use of huge pages.

Well, is actually anybody going to do that?
-- 
Michal Hocko
SUSE Labs