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Date: Thu, 18 Aug 2011 14:03:56 -0700
From: Andi Kleen <ak@linux.intel.com>
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To: Vivek Goyal <vgoyal@redhat.com>
CC: Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH 10/11] VFS: Cache request_queue in struct block_device
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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