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Date: Sun, 15 Dec 2013 14:23:29 +0100
From: Borislav Petkov <bp@alien8.de>
To: John <da_audiophile@yahoo.com>
Cc: Richard Weinberger <richard.weinberger@gmail.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
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        "mingo@redhat.com" <mingo@redhat.com>,
        "x86@kernel.org" <x86@kernel.org>, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] expand micro-optimizations in kernel to newer model CPUs
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On Sun, Dec 15, 2013 at 04:42:50AM -0800, John wrote:
> I am using ANOVA to establish that the generic group differs from the
> optimized group.

You probably should run a couple other benchmarks, in addition, for
greater confidence that this optimization actually brings any palpable
improvement and is not just causing code bloat.

For example, last time I did a perf profile of a kernel build on AMD
F15h, the PILERDRIVER "optimization" was actually even a bit worse than
the standard MK8 one.

http://marc.info/?l=linux-kernel&m=138081947417204

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
--