Trial division with CUDA (mmff) -- used, but runs like new!

[aketilander]

George, I wonder if you have any plans to develop the mmff in the future to cover some of the MMs bigger then MM127? For instance MM521, MM607, MM1279, MM2203 and MM2281?

[Prime95]

Sorry, there are no further development plans for mmff

I stopped at MM127 because the grammar school multiplication used in mmff probably is not the best choice for MM521. Best is likely Karatsuba. Also, register pressure will be pretty severe. This makes further development non-trivial.

[aketilander]

Thank you George for the information. I really hope that you, in a few years time, will consider extending mmff if and when you have any spare time. It's a great program. I appreciate it very much!

[ET_]

Originally Posted by aketilander

Thank you George for the information. I really hope that you, in a few years time, will consider extending mmff if and when you have any spare time. It's a great program. I appreciate it very much!

Meanwhile, you can use Mark's gmp-doublemersenne...

Luigi

[tServo]

George,
As per Luigi's request, I am starting to compile some programs for Mac and am
doing mmff first and was wondering what is the reason for the lower limit
of fermatfactor of 29? Is it just because there is some coding work to be done
or is there a technical or mathematical reason? Just wondering.
Thanks for the great program, BTW.
-Marv

[Prime95]

I'm not positive. I probably felt ECM is a better choice for small Fermats.

[tServo]

Originally Posted by Prime95

I'm not positive. I probably felt ECM is a better choice for small Fermats.

So then it's just a matter of adding the code to handle those ranges n'est-ce pas?

[Prime95]

Originally Posted by tServo

So then it's just a matter of adding the code to handle those ranges n'est-ce pas?

Yes.

[Batalov]

Minor update -- v 0.28:

What's new:

The next set of 32 N values in k*2^N+1 Fermat factor testing is available.
The highest testable N is now 223, and the highest bitlevel is 252. Practically, because k<=2^45 are already tested, the highest usable N is 207 (was 175 is version 0.27), but double-checking may find something (known Fermat factors for N=217 (Suyama, 1980) and N=207 (Keller, 1984) are recovered as one of the QC tests).

As always, previous savefiles will not work with 0.28 unless the -nocheck argument is used.

All seven new kernels are thoroughly tested, but let me know if you will get errors anyway.

Keep the factors coming!

[ET_]

Originally Posted by Batalov

Minor update -- v 0.28:

What's new:

The next set of 32 N values in k*2^N+1 Fermat factor testing is available.
The highest testable N is now 223, and the highest bitlevel is 252. Practically, because k<=2^45 are already tested, the highest usable N is 207 (was 175 is version 0.27), but double-checking may find something (known Fermat factors for N=217 (Suyama, 1980) and N=207 (Keller, 1984) are recovered as one of the QC tests).

As always, previous savefiles will not work with 0.28 unless the -nocheck argument is used.

All seven new kernels are thoroughly tested, but let me know if you will get errors anyway.

Keep the factors coming!

Thank you Serge, I'm updating FermatSearch with ths new executable.

2 questions:

- What do you mean with "The highest testable N is now 223, and the highest bitlevel is 252. Practically, because k<=2^45 are already tested, the highest usable N is 207"? The previous limit of mmff-0.27 was N<174; is the actual limit equal to N<208?
- Our previous version was limitd to k>2²⁴. Does this limit still stand?

Luigi

[ET_]

Originally Posted by Batalov

Minor update -- v 0.28:

[...]

Keep the factors coming!

As I am actually lacking a GPU system, may I ask for some volunteering effort? Our site would benefit from an executable version of mmff-0.28 for the main OSes.

Thank you

Luigi