From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: No, really, stop trying to delete slab until you've finished
 making slub perform as well
Date: Wed, 13 Aug 2008 09:31:12 -0500
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References: <20080805210125.A897.KOSAKI.MOTOHIRO@jp.fujitsu.com>	 <48986AC6.5030406@linux-foundation.org>	 <20080813194222.E77F.KOSAKI.MOTOHIRO@jp.fujitsu.com>	 <48A2DD2C.3090602@linux-foundation.org> <2f11576a0808130714k2cd031c4nd6eea3506831cac9@mail.gmail.com>
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Cc: Matthew Wilcox <matthew@wil.cx>,
	Pekka Enberg <penberg@cs.helsinki.fi>,
	akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, Mel Gorman <mel@skynet.ie>,
	andi@firstfloor.org, Rik van Riel <riel@redhat.com>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
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KOSAKI Motohiro wrote:
> 
> I don't mesure it yet. I don't like this patch.
> maybe, it decrease other typical benchmark.

Yes but running with this patch would allow us to verify that we understand
what is causing the problem. There are other solutions like skipping to the
next partial slab on the list that could fix performance issues that the patch
may cause. A test will give us:

1. Confirmation that the memory use is caused by the trylock.

2. Some performance numbers. If these show a regression then we have some
markers that we can measure other solutions against.