From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Thu, 20 Mar 2008 11:29:44 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
Subject: Re: [patch 5/9] slub: Fallback to minimal order during slab page
 allocation
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 <1205989839.14496.32.camel@ymzhang>
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To: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>, Mel Gorman <mel@csn.ul.ie>, Matt Mackall <mpm@selenic.com>, linux-mm@kvack.org
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On Thu, 20 Mar 2008, Zhang, Yanmin wrote:

> page->objects = (PAGE_SIZE << get_order(s->size)) / s->size;
> 
> 
> It'll look more readable and be simplified.

The earlier version of the fallback had that.

However, its a division in a potentially hot codepath.
And some architectures have slow division logic.



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