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Date: Wed, 21 Dec 2016 17:27:02 -0500
From: "Theodore Ts'o" <tytso@mit.edu>
To: George Spelvin <linux@sciencehorizons.net>
Cc: eric.dumazet@gmail.com, Jason@zx2c4.com, ak@linux.intel.com,
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Subject: Re: HalfSipHash Acceptable Usage
Message-ID: <20161221222702.h2vboms776zpgpi4@thunk.org>
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On Wed, Dec 21, 2016 at 01:37:51PM -0500, George Spelvin 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.

And "with enough registers" includes ARM and MIPS, right?  So the only
real problem is 32-bit x86, and you're right, at that point, only
people who might care are people who are using a space-radiation
hardened 386 --- and they're not likely to be doing high throughput
TCP connections.  :-)

					- Ted