Re: [Cfrg] Timing of libsodium, curve25519-donna, MSR ECCLib, and openssl-master

On Wed, Oct 8, 2014 at 10:02 PM, Andrey Jivsov <crypto@brainhub.org> wrote:
> On 10/08/2014 07:05 PM, Michael Hamburg wrote:
>>
>> Whoa, they improved the performance by 50% since the paper and initial
>> patch?!
>
>
> on 09/03/2014 I reported 40% advantage of Curve25519-donna
> (17384.8/12348.9=1.40). Now it's 14% (17383.6/15168.1=1.146). That's on an
> AVX2 machine.
>
> On my older i5 machine (not an AVX2 machine) the ratio is also improved.
> With the same instructions as quoted below:
>
> was 14131.5/5231.7=2.7 (reported on 09/03/2013)
> now: 14251.3/11105.2=1.27
> (apparently due to Montgomery-style assembler code specialized for P-256
> prime)
>
> This is even more interesting. These performance improvements apparently
> cover most of x86 CPUs in use today, clients and servers.

Wouldn't the speedups from reducing the number of field operations by
changing the curve shape stack on top of these? I don't really see the
relevance to picking which wire format to use.

>
>
>>
>>> On Oct 8, 2014, at 6:01 PM, Andrey Jivsov <crypto@brainhub.org> wrote:
>>>
>>> Now that the P-256 enhancements are in the OpenSSL tree, let commands
>>> speak for themselves.
>>>
>>> Type in a Linux terminal on a Haswell machine (no HT, no
>>> SpeedStep/Turboboost) and observe:
>>>
>>> 1. P-256:
>>>
>>> $ git clone git://git.openssl.org/openssl.git A
>>> $ cd A
>>> $ ./config
>>> $ make && apps/openssl speed ecdhp256
>>>
>>> 15078.1 op/s
>>>
>>> 2. X25519:
>>>
>>> $ git clone https://github.com/brainhub/curve25519-donna.git B
>>> $ cd B
>>> $ make speed-curve25519-donna-c64 && ./speed-curve25519-donna-c64
>>>
>>> 17289.4 op/s
>>>
>>> -----------------------------
>>>
>>> 17383.6 / 15168.1 = 14.6% faster
>>>
>>> The difference is about the cost of point decompression/coordinate
>>> conversion (e.g. Edwards coordinate conversion to Montgomery + point
>>> multiplication would have about the same performance as P-256 point
>>> multiplication).
>>>
>>> _______________________________________________
>>> Cfrg mailing list
>>> Cfrg@irtf.org
>>> http://www.irtf.org/mailman/listinfo/cfrg
>
>
> _______________________________________________
> Cfrg mailing list
> Cfrg@irtf.org
> http://www.irtf.org/mailman/listinfo/cfrg

-- 
"Those who would give up Essential Liberty to purchase a little
Temporary Safety deserve neither  Liberty nor Safety."
-- Benjamin Franklin