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Date: Mon, 4 May 2009 06:32:58 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: Tobias Doerffel <tobias.doerffel@gmail.com>,
       "H. Peter Anvin" <hpa@zytor.com>, Willy Tarreau <w@1wt.eu>,
       Thomas Gleixner <tglx@linutronix.de>,
       Suresh Siddha <suresh.b.siddha@intel.com>,
       "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: Specific support for Intel Atom architecture
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On Mon, 4 May 2009 15:14:57 +0200
Ingo Molnar <mingo@elte.hu> wrote:

> 
> * Tobias Doerffel <tobias.doerffel@gmail.com> wrote:
> 
> > Am Sonntag, 3. Mai 2009 08:48:54 schrieb H. Peter Anvin:
> > > Willy Tarreau wrote:
> > > >> $(call cc-option,-march=atom,-march=i686)
> > > >
> > > > if it's an in-order architecture, wouldn't it be better to tune
> > > > for i386 or i486 instead ?
> > >
> > > Possibly.  It would be worth measuring.
> >
> > How would one do that (never benchmarked kernel stuff before)?
> 
> A standard method is to run lmbench and compare the results - 
> lmbench has a built-in 'report comparison between two runs' feature.

well... you're normally REALLY hard pressed to measure compiler
differences this way..... 

normally compiler options get benchmarked using speccpu and the like....


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
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