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Date: Thu, 19 Feb 2009 09:19:57 -0500 (EST)
From: Christoph Lameter <cl@linux-foundation.org>
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To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
cc: Pekka Enberg <penberg@cs.helsinki.fi>,
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       Andrew Morton <akpm@linux-foundation.org>,
       Lin Ming <ming.m.lin@intel.com>,
       "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Subject: Re: [patch] SLQB slab allocator (try 2)
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What could be changed in the patch is to set SLUB_MAX_SIZE depending on
the page size of the underlying architecture.

#define SLUB_MAX_SIZE MAX(PAGE_SIZE, 8192)

So on 4k architectures SLUB_MAX_SIZE is set to 8192 and on 16k or 64k
arches its set to PAGE_SIZE.

And then define

#define SLUB_MAX_KMALLOC_ORDER get_order(SLUB_MAX_SIZE)

which will be 1 on 4k arches and 0 on higher sized arches.

Then also the kmalloc array would need to be dimensioned using
SLUB_MAX_KMALLOC_ORDER.


The definition of SLUB_NAX_KMALLOC_ORDER could be a bit challenging for
the C compiler.