From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: No, really, stop trying to delete slab until you've finished
 making slub perform as well
Date: Mon, 04 Aug 2008 11:35:11 -0500
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Cc: Matthew Wilcox <matthew@wil.cx>,
	Pekka Enberg <penberg@cs.helsinki.fi>,
	akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, Mel Gorman <mel@skynet.ie>,
	andi@firstfloor.org, Rik van Riel <riel@redhat.com>
To: Jamie Lokier <jamie@shareable.org>
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Jamie Lokier wrote:

> The different behaviours of SLAB/SLUB might result in different levels
> of fragmentation, so I wonder if anyone has compared them on MMU-less
> systems or fragmentation-sensitive workloads on general systems.

Never heard of such a comparison.

MMU less systems typically have a minimal number of processors. For that
configuration the page orders are roughly equivalent to slab. Larger orders
come into play with large amounts of processors.