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From: Andi Kleen <ak@suse.de>
To: Mel Gorman <mel@csn.ul.ie>
Subject: Re: [PATCH 0/5] Sizing zones and holes in an architecture independent
	manner V7
Date: Wed, 7 Jun 2006 17:20:22 +0200
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Cc: Andrew Morton <akpm@osdl.org>, davej@codemonkey.org.uk, tony.luck@intel.com,
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> Ok, while true, I'm not sure how it affects performance. The only "real" 
> value affected by present_pages is the number of patches that are 
> allocated in batches to the per-cpu allocator.

It affects the low/high water marks in the VM zone balancer.

Especially for the 16MB DMA zone it can make a difference if you
account 4MB kernel in there or not.

-Andi