From mboxrd@z Thu Jan  1 00:00:00 1970
From: Len Brown <lenb@kernel.org>
Subject: Re: [RFC] - Mapping ACPI tables as CACHED
Date: Thu, 22 Jul 2010 11:52:02 -0400 (EDT)
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References: <20100722152220.GA18290@sgi.com>
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To: Jack Steiner <steiner@sgi.com>
Cc: mingo@elte.hu, tglx@linutronix.de, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org

> The following experimental patch changes the kernel mapping for ACPI tables
> to CACHED. This eliminates the page attibute conflict & allows users to map
> the tables CACHEABLE. This significantly speeds up boot:
> 
> 	38 minutes without the patch
> 	27 minutes with the patch
> 		~30% improvement
> 
> Time to run ACPIDUMP on a large system:
> 	527 seconds without the patch
> 	  8 seconds with the patch

Interesting.

Can you detect a performance differene on a 1-node machine
that doesn't magnify the penalty of the remote uncached access?

thanks,
-Len Brown, Intel Open Source Technology Cetner