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Date: Sun, 24 Feb 2008 13:20:05 +0100
From: Andi Kleen <andi@firstfloor.org>
To: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: mingo@elte.hu, hpa@zytor.com, tglx@linutronix.de, andi@firstfloor.org,
       linux-kernel@vger.kernel.org, Arjan van de Ven <arjan@linux.intel.com>
Subject: Re: [patch 2/2] x86,fpu: lazy allocation of FPU area
Message-ID: <20080224122005.GA13637@one.firstfloor.org>
References: <20080224023547.264625000@linux-os.sc.intel.com> <20080224023547.412501000@linux-os.sc.intel.com>
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On Sat, Feb 23, 2008 at 06:34:39PM -0800, Suresh Siddha wrote:
> Only allocate the FPU area when the application actually uses FPU, i.e., in the
> first lazy FPU trap. This could save memory for non-fpu using apps.

Did you measure this making any difference? 

At least at some point glibc always touched the FPU once to initialize
it.

-andi