Date: Thu, 11 Jun 2009 11:20:50 -0400 (EDT)
From: Christoph Lameter <cl@linux-foundation.org>
To: Pekka Enberg <penberg@cs.helsinki.fi>
cc: linux-kernel@vger.kernel.org, mel@csn.ul.ie, Larry.Finger@lwfinger.net
Subject: Re: [PATCH 2/2] SLUB: Disable debugging if it increases the minimum
 page order
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On Thu, 11 Jun 2009, Pekka Enberg wrote:

> I think my patch is the simplest solution here: it turns off debugging
> for those caches where the metadata bumps up the minimum allocation
> order and I suspect that we disable cache only for 4096 in practice.

There could be other slab caches that would randomly be affected by this.
I ran a couple of times into situations where I had to hack slab to do
debugging of exempted slabs.

> Also note that when we switch back to more aggressive page allocator
> pass-through, we lose SLUB debugging support.

Debugging options can have side effects. Slab debugging is not something
suitable by default for production environments.

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