From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH 10/11] VFS: Cache request_queue in struct block_device
Date: Thu, 18 Aug 2011 14:03:56 -0700
Message-ID: <4E4D7E3C.8060104@linux.intel.com>
References: <1312259893-4548-1-git-send-email-andi@firstfloor.org> <1312259893-4548-11-git-send-email-andi@firstfloor.org> <20110818194245.GJ15413@redhat.com>
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Cc: Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, hch@infradead.org,
	Jens Axboe <jaxboe@fusionio.com>
To: Vivek Goyal <vgoyal@redhat.com>
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> Is the performance gain because of this one less dereference really
> substantial.
Yes it is measurable on a large macro benchmark.

The gain is from doing the prefetch early enough, and that needs the 
additional pointer.

-Andi