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Date: Sat, 14 Jun 2014 02:27:10 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: George Spelvin <linux@horizon.com>
Cc: hpa@linux.intel.com, linux-kernel@vger.kernel.org, mingo@kernel.org,
        price@mit.edu
Subject: Re: random: Benchamrking fast_mix2
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On Sat, Jun 14, 2014 at 01:25:27AM -0400, George Spelvin wrote:
> > When I did a quick comparison of your 64-bit fast_mix2 variant, it's
> > much slower than either the 32-bit fast_mix2, or the original fast_mix
> > alrogithm.
> 
> That is f***ing *bizarre*.  For me, it's *significantly* faster.
> You *are* compiling -m64, right?  Because I agree with you it'd
> be stupid to try to use it on 32-bit machines.

Sorry for not being clear.  My results are similar to yours with -m64.
It was much slower when compiled with -m32.  (Which may have been
obvious, but one of the things I've learned very early on with
benchmarking is you measure, and don't assume, whenever possible....)

	     	    	     	       	       - Ted
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