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Date: Sun, 16 Sep 2012 01:22:20 +0200
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Dimitry Andric <dimitry@andric.com>
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Cc: freebsd-current@FreeBSD.org, freebsd-toolchain@FreeBSD.org
Subject: Re: Compiler performance tests on FreeBSD 10.0-CURRENT
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On Sun, Sep 16, 2012 at 12:34:45AM +0200, Dimitry Andric wrote:
> Hi all,
> 
> By request, I performed a series of kernel performance tests on FreeBSD
> 10.0-CURRENT, particularly comparing the runtime performance of GENERIC
> kernels compiled by gcc 4.2.1 and by clang 3.2.

the fact that the difference is so small is interesting,
and it might almost suggests that the test is dominated by
other factors than the compiler. By chance do you have a
way to produce other data points with different optimization
levels in the compiler ?

cheers
luigi