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Date: Wed, 21 Dec 2016 19:40:12 +0100
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Subject: Re: HalfSipHash Acceptable Usage
To: George Spelvin <linux@sciencehorizons.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>, Andi Kleen <ak@linux.intel.com>,
        David Miller <davem@davemloft.net>,
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        Tom Herbert <tom@herbertland.com>,
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        "Theodore Ts'o" <tytso@mit.edu>,
        Vegard Nossum <vegard.nossum@gmail.com>
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On Wed, Dec 21, 2016 at 7:37 PM, George Spelvin
<linux@sciencehorizons.net> wrote:
> SipHash annihilates the competition on 64-bit superscalar hardware.
> SipHash dominates the field on 64-bit in-order hardware.
> SipHash wins easily on 32-bit hardware *with enough registers*.
> On register-starved 32-bit machines, it really struggles.
>
> As I explained, in that last case, SipHash barely wins at all.
> (On a P4, it actually *loses* to MD5, not that anyone cares.  Running
> on a P4 and caring about performance are mutually exclusive.)

>From the discussion off list which examined your benchmark code, it
looks like we're going to move ahead with SipHash.