GPU to 72 status...

[chalsall]

Originally Posted by davieddy

Now how about fast reliable LL testers allocated 60M expos, leaving the tail to new/slower participants?

Like you, pray tell?

[ET_]

Originally Posted by davieddy

That's the most sensible suggestion I've heard from you (which isn't saying much).

Now how about fast reliable LL testers allocated 60M expos, leaving the tail to new/slower participants?

D

I'm working on it since 6/2012...

Luigi

[Aramis Wyler]

While I've been contributing to prime95 for more years than I can remember, I've been mostly oblivious about what numbers are assigned to me or where the current wavefront is or if potential ll numbers have been sufficiently pre-factored.

While I still run first time LL tests on my cpus, I've been trying lately to do trial factoring on my GPU. I was getting them straight from prime95 until I realised that being a part of GPU to 72 didn't mean joining a prime95 team, per se. Since then (the other day) I've been getting my numbers from them.

Still, I'm having trouble working out where the work most needs done. I queued up a week or so of TF'ing 60m range primes to 73, but despite using the visualization tool I'm having a hard time following exactly where the wavefront is, and if I should be factoring a larger set to 71, then 72, then maybe 73 rather than factoring a number up to 73 then moving on to the next.

Also it seems like new 100m digit primes (the next prize) aren't being factored in the gpu to 72 project, or if they are I can't parse it out.

Basicly I'm looking for help interpreting the relevant graphs on where the ll wavefront is, how fast it's moving, and where the TF wavefront is and how fast it's moving. I suspect there may be multiple LL wavefronts, one in the 60m range (?) and one in the 100m range.

[chalsall]

Originally Posted by Aramis Wyler

Still, I'm having trouble working out where the work most needs done. I queued up a week or so of TF'ing 60m range primes to 73, but despite using the visualization tool I'm having a hard time following exactly where the wavefront is, and if I should be factoring a larger set to 71, then 72, then maybe 73 rather than factoring a number up to 73 then moving on to the next.

The most important work, at the moment, is trial factoring (TFing) to 73 in the 61M range. If you (or anyone) doesn't take the candidates to 73 there, then someone else will have to.

Originally Posted by Aramis Wyler

Also it seems like new 100m digit primes (the next prize) aren't being factored in the gpu to 72 project, or if they are I can't parse it out.

You are correct -- candidates above 65M are not available from the GPU72 project currently. The "100m" factoring project you are probably thinking about is coordinated by Uncwilly here.

Originally Posted by Aramis Wyler

Basicly I'm looking for help interpreting the relevant graphs on where the ll wavefront is, how fast it's moving, and where the TF wavefront is and how fast it's moving. I suspect there may be multiple LL wavefronts, one in the 60m range (?) and one in the 100m range.

It's a little complicated... But basically there's really only one LL wavefront -- currently at just above 60M. This chart, vs this will (hopefully) help you.

(Yes, the next prize is in the 332M range, but very few people expend the months or years required to do a single LL test up there -- our goal is to find the next biggest known prime, not to win money.)

[Aramis Wyler]

Thank you very much!

[Prime95]

Originally Posted by Aramis Wyler

Still, I'm having trouble working out where the work most needs done.

The short answer (chalsall will correct me if I'm wrong): It doesn't matter -- don't sweat it.

Ideally, all 60M exponents will be TF'ed to at least 2^73 by a GPU. GPU72 will make sure this happens. If you only TF to 2^71, then GPU72 will reassign the number to someone else to take it the rest of the way. Either way (doing it in stages or all at once), the work is needed and will get done.

If I were you, I'd either a) go straight to 2^73 to reduce the headache of getting assignments and reporting results, or b) only go to the next bit level to maximize the "thrill" of finding more factors per unit of GPU time. Your personal preferences will dictate your choice.

The 100M exponents are mostly for the fool-hearty. I'd only TF a 100M exponent if requested by a user with a respected reputation.

[Uncwilly]

Originally Posted by Prime95

The 100M exponents are mostly for the fool-hearty. I'd only TF a 100M exponent if requested by a user with a respected reputation.

Thanks for that ringing endorsement.

I think that the running of LL's on 100M exponents is not wise ATM. I am trying to make sure that those that do start them, have numbers that have had enough TF on them to make sure that they are not squandering their effort (when it could have been factored reasonably.)

[lycorn]

GPUto72 has just found the 10000th factor!
Congrats to all involved.

[chalsall]

Just putting this out there for discussion...

A user e-mailed me asking why we're not taking DCTF to 77 instead of 70. I pointed them to James' analysis and (hopefully) explained that even with the new GPU seiving it would only make sense to go to 71 in the current range we're working. And, also, that the LLTF work is really the most important at the moment.

However, it raises the question: for those who are doing DCTF work (where we're currently over 500 days ahead of the wave), should we bump the release level to 71, and perhaps bring back in some candidates in the 30M, 31M and 32M regions to go from 70 to 71?

While I personally don't think this is the best thing for GIMPS, I also think that people should be able to do what they want to do.

Is this wanted by anyone?

If so, I'd suggest we simply increase the current release level for DCTF, and bring in a few candidates at a time at the top of 30M for processing, and work down until we meet the wavefront, Then start working upwards from 31M.

Thoughts?

[Prime95]

Originally Posted by chalsall

should we bump the release level to 71, and perhaps bring back in some candidates in the 30M, 31M and 32M regions to go from 70 to 71?

No. James' table improperly estimates the DCTF crossover. Since these exponents have already had P-1 done, TF to 2^71 will find fewer factors than LLTF. James should be able to compute a "proper" crossover based on finding approximately 1 factor per 100 DCTF exponents (GPU72 should be able refine this approximation by calculating how many factors are being found DCTFing to 2^70).

[chalsall]

Originally Posted by Prime95

Since these exponents have already had P-1 done, TF to 2^71 will find fewer factors than LLTF.

Very good point. Supported by the statistics.