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Date: Tue, 24 Apr 2007 11:06:34 -0700
From: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
To: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>,
       William Lee Irwin III <wli@holomorphy.com>, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Con Kolivas <kernel@kolivas.org>, Nick Piggin <npiggin@suse.de>,
       Mike Galbraith <efault@gmx.de>, Arjan van de Ven <arjan@infradead.org>,
       Peter Williams <pwil3058@bigpond.net.au>,
       Thomas Gleixner <tglx@linutronix.de>, caglar@pardus.org.tr,
       Willy Tarreau <w@1wt.eu>, Gene Heskett <gene.heskett@gmail.com>
Subject: Re: [patch] CFS scheduler, v3
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On Tue, Apr 24, 2007 at 10:55:45AM -0700, Christoph Lameter wrote:
> On Tue, 24 Apr 2007, Siddha, Suresh B wrote:
> > yes, we were planning to move this to a different percpu section, where
> > all the elements in this new section will be cacheline aligned(both
> > at the start, aswell as end)
> 
> I would not call this a per cpu area. It is used by multiple cpus it 
> seems. 

not decided about the name yet. but the area is allocated per cpu and yes,
the data can be referred by other cpus.

> But for 0.5%? on what benchmark? Is is really worth it?

famous database workload :)

I don't think the new section will be added for this 0.5%. This is a straight
fwd optimization, and anyone can plug into this new section in future.

thanks,
suresh