Date: Wed, 22 Jul 2015 14:25:58 +0300
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Eric B Munson <emunson@akamai.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Michal Hocko <mhocko@suse.cz>,
        Vlastimil Babka <vbabka@suse.cz>,
        Paul Gortmaker <paul.gortmaker@windriver.com>,
        Chris Metcalf <cmetcalf@ezchip.com>,
        Guenter Roeck <linux@roeck-us.net>, linux-alpha@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mips@linux-mips.org,
        linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org,
        linux-mm@kvack.org, linux-arch@vger.kernel.org,
        linux-api@vger.kernel.org
Subject: Re: [PATCH V4 5/6] mm: mmap: Add mmap flag to request VM_LOCKONFAULT
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On Tue, Jul 21, 2015 at 03:59:40PM -0400, Eric B Munson wrote:
> The cost of faulting in all memory to be locked can be very high when
> working with large mappings.  If only portions of the mapping will be
> used this can incur a high penalty for locking.
> 
> Now that we have the new VMA flag for the locked but not present state,
> expose it as an mmap option like MAP_LOCKED -> VM_LOCKED.

What is advantage over mmap() + mlock(MLOCK_ONFAULT)?

-- 
 Kirill A. Shutemov
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