My first LL test and a few quetions

[ONeil]

Hi all,

10 years ago I tried to find a mersenne prime using Gimps on my slow computer. I had no luck. Well now I'm testing a prime number that is a little larger than the one that was found to be the 49th mersenne.

Right off the bat it is testing it with Lucas Lemer and it will be completed Jan 8, 2017. My question is are there other tests? What are they? How long will the entire process take if all tests are passed stating its a Mersenne if it is one? Here is my computer specs if you need that to make any calculation.

[CRGreathouse]

There are two tests that can discover Mersenne primes: Lucas-Lehmer and the Gerbicz PRP test. Only the former can prove their primality, but that's just a formality -- once discovered with either test candidates need to be checked with LL on a number of different systems.

The other tests, trial division and P-1, support these main tests by weeding out composite candidates to reduce wasted effort.

[ONeil]

Originally Posted by CRGreathouse

There are two tests that can discover Mersenne primes: Lucas-Lehmer and the Gerbicz PRP test. Only the former can prove their primality, but that's just a formality -- once discovered with either test candidates need to be checked with LL on a number of different systems.

The other tests, trial division and P-1, support these main tests by weeding out composite candidates to reduce wasted effort.

Is there a formula for the time it would take knowing my PC stats or do you know how much time this will take if indeed my number is mersenne? What I'm getting at is this a 180 day test or a couple years?

[science_man_88]

Originally Posted by ONeil

Is there a formula for the time it would take knowing my PC stats or do you know how much time this will take if indeed my number is mersenne? What I'm getting at is this a 180 day test or a couple years?

which version of the software is being used also matters potentially.

[ONeil]

Originally Posted by science_man_88

which version of the software is being used also matters potentially.

Windows 64 Prime95 Version V 29.4 Build 5

[science_man_88]

Originally Posted by ONeil

Windows 64 Prime95 Version V 29.4 Build 5

there may be software timings for that hardware,that may help you figure it out, though I don't know the link. found the listings: https://www.mersenne.org/report_benc...ic_cpu=4374623 is the closest I found in the data myself. of course you can just multiply average ms per iteration by iterations and get a very very rough result.

[VictordeHolland]

In Prime95, go to Test---> Status
There should be an estimated completion date there.

Other option is to login on mersenne.org and check your current assignments there. It could take a few days to get a good estimate, depending on your PCs uptime/time P95 is allowed to run.

[ONeil]

Originally Posted by VictordeHolland

In Prime95, go to Test---> Status
There should be an estimated completion date there.

Other option is to login on mersenne.org and check your current assignments there. It could take a few days to get a good estimate, depending on your PCs uptime/time P95 is allowed to run.

Thanks for your reply it does say due Jan 8, 2017 but will I have go through more tests? So what is the combined amount of time for completion? And thank you all for your responses.

[retina]

Originally Posted by ONeil

Thanks for your reply it does say due Jan 8, 2017 but will I have go through more tests? So what is the combined amount of time for completion? And thank you all for your responses.

Jan 8, 2017 was about 11 months ago.

However usually tests on exponents in the 70-80 million range will be from a few days to a few months. The time greatly depends upon your system specs and how you configured P95, plus lots of other factors like whether your system runs 24/7 and if other processes are using CPU cycles and/or memory swapping etc.

Also note that the estimated completion times will change during the test, sometimes by a lot, and they usually move further into the future as it progresses.

After the test is finished someone else will verify the result later. You can move on to another test and try again with a new exponent.

[potonono]

The Lucas-Lehmer (LL) test your machine is running is the only test your machine will need to run in order to determine if your candidate prime number is a Mersenne prime. That type of test gives a specific Yes/No result. Don't be discouraged, but the likely result will be that your candidate prime number is not a Mersenne prime, but it certainly could be.

The test will likely complete sometime around the estimated date. Tests can run longer if the machine spends any time doing other work, but if you do decide to test additional candidate numbers after your current candidate number, you'll probably get a good idea of how long your machine will take for each result for numbers around the same size.

[ONeil]

Originally Posted by retina

Jan 8, 2017 was about 11 months ago.

However usually tests on exponents in the 70-80 million range will be from a few days to a few months. The time greatly depends upon your system specs and how you configured P95, plus lots of other factors like whether your system runs 24/7 and if other processes are using CPU cycles and/or memory swapping etc.

Also note that the estimated completion times will change during the test, sometimes by a lot, and they usually move further into the future as it progresses.

After the test is finished someone else will verify the result later. You can move on to another test and try again with a new exponent.

Oops error it should say 2018 my bad mistake lol.