Subject: Re: tbench regression - Why process scheduler has impact on tbench
	and why small per-cpu slab (SLUB) cache creates the scenario?
From: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <clameter@sgi.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>, mingo@elte.hu
In-Reply-To: <200709081808.42421.nickpiggin@yahoo.com.au>
References: <1188953218.26438.34.camel@ymzhang>
	 <1188969725.26438.46.camel@ymzhang>
	 <Pine.LNX.4.64.0709050006330.7567@schroedinger.engr.sgi.com>
	 <200709081808.42421.nickpiggin@yahoo.com.au>
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Date: Mon, 10 Sep 2007 08:56:32 +0800
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On Sat, 2007-09-08 at 18:08 +1000, Nick Piggin wrote:
> On Wednesday 05 September 2007 17:07, Christoph Lameter wrote:
> > On Wed, 5 Sep 2007, Zhang, Yanmin wrote:
> > > > slub_max_order=3 slub_min_objects=8
> > >
> > > I tried this approach. The testing result showed 2.6.23-rc4 is about
> > > 2.5% better than 2.6.22. It really resovles the issue.
> >
> > Note also that the configuration you tried is the way SLUB is configured
> > in Andrew's tree.
> 
> It still doesn't sound like it is competitive with SLAB at the same sizes.
> What's the problem?
Process scheduler and small SLUB per-cpu cache work together to create the tebnch regression.

Pls. see the starting of the thread.

-yanmin
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