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Date: Wed, 26 Jul 2006 12:31:01 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: Manfred Spraul <manfred@colorfullife.com>
cc: Pekka J Enberg <penberg@cs.helsinki.fi>,
       Heiko Carstens <heiko.carstens@de.ibm.com>,
       Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org,
       linux-mm@kvack.org, Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: Re: [patch 2/2] slab: always consider arch mandated alignment
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On Wed, 26 Jul 2006, Manfred Spraul wrote:

> > So we sacrifice the ability to worsen the performance of slabs by
> > misaligning them for debugging purposes.
> >  
> If a slab user can live with misaligned objects, then he shouldn't set align.
> Thus we do not sacrifice anything.

A slab user is setting alignment in order to optimize performance not for 
correctness. Most users that I know of can live with misalignments. If 
that would not be the case then this code would never have worked.