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Date: Mon, 21 Nov 2011 15:33:09 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Wu Fengguang <fengguang.wu@intel.com>
Cc: Linux Memory Management List <linux-mm@kvack.org>,
        <linux-fsdevel@vger.kernel.org>, Andi Kleen <andi@firstfloor.org>,
        Li Shaohua <shaohua.li@intel.com>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 7/8] readahead: basic support for backwards prefetching
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On Mon, 21 Nov 2011 17:18:26 +0800
Wu Fengguang <fengguang.wu@intel.com> wrote:

> Add the backwards prefetching feature. It's pretty simple if we don't
> support async prefetching and interleaved reads.

Well OK, but I wonder how many applications out there read files in
reverse order.  Is it common enough to bother special-casing in the
kernel like this?