Re: [openpgp] SHA-x performance

Peter Gutmann <> Wed, 12 August 2015 02:08 UTC

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From: Peter Gutmann <>
To: Werner Koch <>
Thread-Topic: [openpgp] SHA-x performance
Date: Wed, 12 Aug 2015 02:08:33 +0000
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Cc: IETF OpenPGP <>, Derek Atkins <>, Phillip Hallam-Baker <>, Daniel Kahn Gillmor <>, ianG <>
Subject: Re: [openpgp] SHA-x performance
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Werner Koch <> writes:

>Do you have a suggestion on what CPUs from low to high end to do benchmarks
>so to check which SHA variant is suitable?

It'd be a longish list :-).  I'm also not sure how easy it'll be to get at
them, this is all embedded-systems stuff so you can't just SSH into a box and
run the tests.  In any case the most common is ARM Cortex M (and a few R), so
any Cortex M3 (the example I gave was an STM32 at 180MHz which admittedly is
the top end of the range, 100 or 80 Mhz would be another benchmark level, but
then they're all ARMv7-M so you can extrapolate from one clock speed to
another), then for PowerPC something like an MPC560x at 80 MHz (very common in
industrial and automotive), a PIC32MX (MIPS32) at 60 MHz, and then for exotica
maybe a NIOS II or MicroBlaze at 100 Mhz.  You don't really need to do dozens
of variants since things mostly scale directly with clock speed, and in any
case those are reasonably representative clocks, at least for the faster devices
where power-saving isn't an issue.