Help stabilising mini-gmp

Marco Bodrato bodrato at
Mon Nov 21 20:30:58 UTC 2016


Il Lun, 21 Novembre 2016 6:47 pm, Niels Möller ha scritto:
> tg at (Torbjörn Granlund) writes:
>> Of the remaining issues I
>> worry most about #2.  Marco adjusted the parameters to make it faster,
>> but I remain unconvinced that really needed 400
>> seconds for the test with old parameters.  I suspect the code can hang
>> for certain seeds.  (We cannot tell the seed because of #1.)
> If it happens again, the seed should be printed out.

I tried the test on a 18-years old 32-bits CPU I'm currently using. A
single 8000-bit Miller-Rabin round took 20 seconds with mini-gmp.
That's why I reduced the size. With 2000-bit operands I assume the worst
execution time will be reduced by a factor 18.

The hypothesis "its time varies hugely" is surely true. Before the
changeset 17099, on my machine, fluctuations between 2 and 60 seconds
where the norm. Of course a seed that require many MR rounds on big
operands is unlikely...

Best regards,


More information about the gmp-devel mailing list