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Date: Wed, 18 Dec 2013 10:51:48 +0200
From: Pekka Enberg <penberg@iki.fi>
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To: Dave Hansen <dave@sr71.net>, Andrew Morton <akpm@linux-foundation.org>
CC: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Pravin B Shelar <pshelar@nicira.com>,
        Christoph Lameter <cl@linux-foundation.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Andi Kleen <ak@linux.intel.com>, Pekka Enberg <penberg@kernel.org>
Subject: Re: [RFC][PATCH 0/7] re-shrink 'struct page' when SLUB is on.
References: <20131213235903.8236C539@viggo.jf.intel.com> <20131216160128.aa1f1eb8039f5eee578cf560@linux-foundation.org> <52AF9EB9.7080606@sr71.net>
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On 12/17/2013 02:45 AM, Dave Hansen wrote:
> I'll do some testing and see if I can coax out any delta from the
> optimization myself.  Christoph went to a lot of trouble to put this
> together, so I assumed that he had a really good reason, although the
> changelogs don't really mention any.

IIRC it's commit 8a5ec0b ("Lockless (and preemptless) fastpaths for 
slub") that documents the performance gains.

The page alignment patches came later once we discovered that we broke 
the world...

                         Pekka