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Date: Tue, 1 Mar 2016 00:03:40 +0300
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-mm <linux-mm@kvack.org>,
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Subject: Re: [PATCH] mm: readahead: do not cap readahead() and MADV_WILLNEED
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On Mon, Feb 29, 2016 at 02:41:59PM -0500, Johannes Weiner wrote:
> That, or switch to read() from a separate thread for cache priming.

mmap(MAP_POPULATE) would save you some copy_to_user() overhead, comparing
to read().

-- 
 Kirill A. Shutemov