PrimeGrid Questions

[GLeeM]

Finally realized I am in sixth place for the TeAm with 68M points and I don't have a prime

That's what happens when all you run is sieve

So I started running some PPSE short WUs and have been looking my "All Tasks" pages.

Questions:
1. For tasks that have a quorum of two - does the first to send in the result get credit for the prime or is it the first to get the task?
I'm guessing it is the first to send in the result and so have set my buffer to zero in hopes of increasing odds of being discoverer instead of the wingman proofer.

2. Will having a low buffer increase the number of resent tasks I get?

3. Why do some tasks have a quorum of one? If they have the same chances of being prime, how do I get more of them?

4. Which projects have the best odds of finding a prime?

5. What else can I do to better find a prime?

Thanks for any help you can give

 

[Ken g6]

1. For tasks that have a quorum of two - does the first to send in the result get credit for the prime or is it the first to get the task?
I'm guessing it is the first to send in the result and so have set my buffer to zero in hopes of increasing odds of being discoverer instead of the wingman proofer.

Correct.

2. Will having a low buffer increase the number of resent tasks I get?

Huh. I don't know. The first one to return the task gets the prime, so some resends, where no one has completed the task yet, might still get you your own prime.

3. Why do some tasks have a quorum of one? If they have the same chances of being prime, how do I get more of them?

As I recall they have a smart quorum system. The more good results your computer returns, the more quorum-one tasks you get.

4. Which projects have the best odds of finding a prime?

5. What else can I do to better find a prime?

There's some good suggestions here.

Currently, the fastest opportunity to find Top 5000 primes is with the SGS (LLR) project.

If you ran a PRPNet project, which isn't BOINC but gets BOINC credit, you wouldn't have any double-checkers. But I don't think any of those give odds as good as SGS right now.

If you've done that much with sieve, you must also have GPUs. You could try running them on GFN too. The chances of getting a prime are very small, but the prime you would get would be very large.

Enabling auto-reporting is a good idea too; otherwise you'll have to learn to use the top-5000 primes site.

Good luck!

 

[GLeeM]

Thanks Ken_g6

 

[kowalabearhugs]

Any idea what percentage of users has found a prime? I'm at 5.1m (3.1 seive, 2 llr/genfer).

 

[GLeeM]

http://www.primegrid.com/primes/?section=topusers&by=total_fp

I think that is worldwide.

Nine have thousands.
104 people have hundreds
527 have ten or more
1961 have one or more

 

[petrusbroder]

Interesting ... Ijust checked and found to my surprise that I have found 10 primes: three as a primary cruncher, 7 as a doublechecker.
I wonder if there is a correlation between the number of points (or WUs) one has crunched and the number of primes one has found.

 

[petrusbroder]

OK, I checked for the top 1000 prime founders and there was no significant linear correlation between BOINC-points and number of primes found irrespective if you were primary or doublechecker or the sum of those two. I did not check other correlations ...

 

[Ken g6]

I wonder if there is a correlation between the number of points (or WUs) one has crunched and the number of primes one has found.

Not significantly, no. It depends mostly on the size of the numbers tested, so it depends as much on what project was worked on as on how many points were obtained.

 

[GLeeM]

After checking maybe 500 WUs from my two Hazwell computers over two days, I found ZERO quorum 2 WUs where I received the WU first.
I always get it anywhere from 3 to 12 minutes (or three days) after the first person gets it.

I am doing PPSE and have my buffer set to 0.00 days.

Ken, I checked a few of your WUs, and although most are quorum 1, I did not see any that you got first, either!

I could see this happening some because of the low buffer, but you'd think I should see a few that I received first?

 

[biodoc]

GLeeM, I see you have one double checker. Is that recent?

I have four of each but none last year or this year.

1 for PPS and 7 for Sophie Germain. I have completed 22580 WUs and 373K points for Sophie.

I only crunch PrimeGrid during races (CPUs anyway)

 

[GLeeM]

I see you have one double checker. Is that recent?

Huh, didn't know about that one. It is recent, within the last week or so, I think.

Do they send notification about double-checkers? I did not receive any notice.

 

[GLeeM]

3705*2^1320407+1 is prime!!!

397,486 digits. Enough to make Top 5000 List
Rank: 2,232
Time: 10.4 minutes

It is from a PPSE WU (quorum=2). Completed tasks 15,767. Credit 572,015.28

Besides running short WUs, (SGS or PPSE), on a fast AVX computer, I think the best advice it to run with no buffer. You'll get a few more resends, (and almost always be the second to receive the WU), but you'll finish more WUs before the other guy.

Extra thanks to Ken_g6 for the help :thumbsup:

EDIT: I suspect this WU might have been a quorum=1 until I sent it back as prime. It was not sent out to the second person until after I sent it back.

 

[biodoc]

3705*2^1320407+1 is prime!!!

397,486 digits. Enough to make Top 5000 List
Rank: 2,232
Time: 10.4 minutes

Congrats GLeeM! :thumbsup:

 

[biodoc]

3705*2^1320407+1 is prime!!!

397,486 digits. Enough to make Top 5000 List
Rank: 2,232
Time: 10.4 minutes

Congrats GLeeM! :thumbsup:

 

[GLeeM]

Congrats GLeeM!

We'll call your double post - efficient!

Because I found another prime

4289*2^1303015+1 is prime!!!

Completed tasks = 25,002
Credit = 847,200

 

[petrusbroder]

Congrats, GLeeM!
Often it is like this: for a long time no primes, then a number of them.

 

[TennesseeTony]

Often it is like this: for a long time no primes, then a number of them.

They like hiding in groups because, ahem, "there is strength in numbers."

 

[biodoc]

Congrats on another Prime, GLeeM! :thumbsup:

I'll try not to Double post this time!