Date: Fri, 12 Nov 2010 09:13:40 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
To: Richard Kennedy <richard@rsk.demon.co.uk>
cc: Pekka Enberg <penberg@kernel.org>, lkml <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>
Subject: Re: [PATCH/RFC] MM slub: add a sysfs entry to show the calculated
 number of fallback slabs
In-Reply-To: <1289561309.1972.30.camel@castor.rsk>
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References: <1289561309.1972.30.camel@castor.rsk>
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On Fri, 12 Nov 2010, Richard Kennedy wrote:

> On my desktop workloads (kernel compile etc) I'm seeing surprisingly
> little slab fragmentation. Do you have any suggestions for test cases
> that will fragment the memory?

Do a massive scan through huge amounts of files that triggers inode and
dentry reclaim?

> + * Note that this can give the wrong answer if the user has changed the
> + * order of this slab via sysfs.

Not good. Maybe have an additional counter in kmem_cache_node instead?
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