From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Nicol <davidnicol@gmail.com>
Subject: Re: [PATCH v3 0/5]add new ioctls to do metadata readahead in btrfs
Date: Wed, 19 Jan 2011 15:33:28 -0600
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Cc: Shaohua Li <shaohua.li@intel.com>,
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	Arjan van de Ven <arjan@infradead.org>,
	"Yan, Zheng" <zheng.z.yan@linux.intel.com>,
	"Wu, Fengguang" <fengguang.wu@intel.com>,
	linux-api <linux-api@vger.kernel.org>,
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To: Andrew Morton <akpm@linux-foundation.org>
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On Wed, Jan 19, 2011 at 2:34 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:

> It would be much more valuable if those 3.5 seconds were available to
> devices which really really care about bootup times, but very few of
> those devices use rotating disks nowadays, I expect?

And don't rotating disk modules read and buffer whole tracks, doing
their own readahead, anymore, anyway? Isn't that part of what "on-disk
cache" does?