Welcome to Summer Solstice Challenge

The longest day of the year is drawing near and to mark this turning point in the year, PrimeGrid is offering a 5 day challenge on Proth MEGA Prime Search (LLR). Only PPS MEGA is part of the challenge!

To participate in the Challenge, please select only the Proth MEGA Prime Search (LLR) project in your PrimeGrid preferences section. The challenge will begin 20 June 2016 22:34 UTC and end 25 June 2016 22:34 UTC. Application builds are available for Linux , Windows and MacIntel 32 bit and 64 bit. CPU's with AVX capabilities will be significantly faster than the ones without, as this instruction set allows for more computing power.

Please note the atypical start and stop times of this challenge!

ATTENTION: The primality program LLR is CPU intensive; so, it is vital to have a stable system with good cooling. It does not tolerate "even the slightest of errors." Please see this post for more details on how you can "stress test" your computer. WU's will take just under 2 hours on the fastest/newest computers and 3(+) hours on slower/older computers. If your computer is highly overclocked, please consider "stress testing" it. Sieving is an excellent alternative for computers that are not able to LLR. :)

Highly overclocked Haswell (i.e., Intel Core i7, i5, and i3 -4xxx) computers running the application will see fastest times. Note that PPS is now running the latest, brand new FMA3 version of LLR which takes full advantage of the new Haswell features. It's faster than the previous LLR app and draws more power and produces more heat. The new FMA3 LLR app is version 6.24. If you have a Haswell CPU, especially if it's overclocked or has overclocked memory, and haven't run the new FMA3 LLR before, we strongly suggest running it before the challenge while you are monitoring the temperatures.

Please, please, please make sure your machines are up to the task.

Time zone converter:

The World Clock - Time Zone Converter

NOTE: The countdown clock on the front page uses the host computer time. Therefore, if your computer time is off, so will the countdown clock. For precise timing, use the UTC Time in the data section to the left of the countdown clock.

Scoring Information

Scores will be kept for individuals and teams. Only work units issued AFTER 20 June 2016 22:34 UTC and received BEFORE 23 April 2014 2014 16:16 UTC will be considered for credit. We will use the same scoring method as for BOINC credit. The only difference is that the primary and double checker of a WU will receive the same score.

Therefore, each completed WU will earn a unique score based on its n value. The higher the n, the higher the score. This is different than BOINC cobblestones! A quorum of 2 is NOT needed to award Challenge score - i.e. no double checker. Therefore, each returned result will earn a Challenge score. Please note that if the result is eventually declared invalid, the score will be removed.

For details on how the score is calculated, please see this thread.

At the Conclusion of the Challenge

We kindly ask users "moving on" to ABORT their WU's instead of DETACHING, RESETTING, or PAUSING.

ABORTING WU's allows them to be recycled immediately; thus a much faster "clean up" to the end of an LLR Challenge. DETACHING, RESETTING, and PAUSING WU's causes them to remain in limbo until they EXPIRE. Therefore, we must wait until WU's expire to send them out to be completed.

Please consider either completing what's in the queue or ABORTING them. Thank you. :)

About the Proth Prime Search

The Proth Prime Search is done in collaboration with the Proth Search project. This search looks for primes in the form of k*2^n+1. With the condition 2^n > k, these are often called Proth primes. This project also has the added bonus of possibly finding factors of "classical" Fermat numbers or Generalized Fermat numbers. As this requires PrimeFormGW (PFGW) (a primality-testing program), once PrimeGrid finds a prime, it is then tested on PrimeGrid's servers for divisibility.

Proth Search only searches for k<1200. PrimeGrid created an extension to that which includes all candidates 1200<k<10000 for n<5M. It is this extension which we call PPSE that the Challenge will be on.

Initially, PrimeGrid's PPS project's goal was to double check all previous work up to n=500K for odd k<1200 and to fill in any gaps that were missed. We have accomplished that now and have increased it to n=2M. PG's LLRNet searched up to n=200,000 and found several missed primes in previously searched ranges. Although primes that small did not make it into the Top 5000 Primes database, the work was still important as it may have led to new factors for "classical" Fermat numbers or Generalized Fermat numbers. While there are many GFN factors, currently there are only 293 "classical" Fermat number factors known. Current primes found in PPS definitely make it into the Top 5000 Primes database.


For more information about "Proth" primes, please visit these links:

• Proth Prime - The Prime Glossary
  
• Proth Prime - Wolfram MathWorld
  
• Proth Number - Wikipedia

About Proth Search

The Proth Search project was established in 1998 by Ray Ballinger and Wilfrid Keller to coordinate a distributed effort to find Proth primes (primes of the form k*2^n+1) for k < 300. Ray was interested in finding primes while Wilfrid was interested in finding divisors of Fermat number. Since that time it has expanded to include k < 1200. Mark Rodenkirch (aka rogue) has been helping Ray keep the website up to date for the past few years.

Early in 2008, PrimeGrid and Proth Search teamed up to provide a software managed distributed effort to the search. Although it might appear that PrimeGrid is duplicating some of the Proth Search effort by re-doing some ranges, few ranges on Proth Search were ever double-checked. This has resulted in PrimeGrid finding primes that were missed by previous searchers. By the end of 2008, all new primes found by PrimeGrid were eligible for inclusion in Chris Caldwell's Prime Pages Top 5000. Sometime in 2009, over 90% of the tests handed out by PrimeGrid were numbers that have never been tested.

PrimeGrid intends to continue the search indefinitely for Proth primes.

What is LLR?

The Lucas-Lehmer-Riesel (LLR) test is a primality test for numbers of the form N = k*2^n − 1, with 2^n > k. Also, LLR is a program developed by Jean Penne that can run the LLR-tests. It includes the Proth test to perform +1 tests and PRP to test non base 2 numbers. See also:

• Lucas-Lehmer-Riesel test (WIKI)
  
• Download LLR by Jean Penné
  

(Edouard Lucas: 1842-1891, Derrick H. Lehmer: 1905-1991, Hans Riesel: 1929-2014).
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PrimeGrid Challenge Overall standings --- Last update: From Pi to Paddy (2016)

WU's will take just under 2 hours on the fastest/newest computers and 3(+) hours on slower/older computers.

That link isn't working for me, but my main i7-6700k at 4.2 GHz does 4 MEGA units every 44 minutes. I'm going to have a go at overclocking my 2nd 6700k next weekend as I just fitted a bigger cooler last weekend... :)

That link isn't working for me, but my main i7-6700k at 4.2 GHz does 4 MEGA units every 44 minutes. I'm going to have a go at overclocking my 2nd 6700k next weekend as I just fitted a bigger cooler last weekend... :)

6600k OC much?

6600k OC much?

6600k OC much?

4332.25 core, 4231.5 cache, 3021 RAM (yay baseclock).

There's some variance on the WU speed, though. Half of them are taking just over 43min, while the other half is getting shy of 47.

6600k OC much?

4332.25 core, 4231.5 cache, 3021 RAM (yay baseclock).

There's some variance on the WU speed, though. Half of them are taking just over 43min, while the other half is getting shy of 47.

Rafael,

You've got several inconclusives and invalids on the machine over the last couple of months, but none in the last week. Is that a problem that you've corrected, or is it an ongoing problem where a small percentage of tasks have errors?

I'm wondering if Skylakes are not quite totally stable yet.

To add to that, pretty much all the bad WUs I've ever produced on Skylake were due to running aggressive settings on ram. Even if the ram is rated for higher speeds, it is still a system level overclock. For bigger units, it can provide quite a big boost to performance, so the temptation is there to push it. I've not really OC'd the CPU as much since there is a bigger power/performance tradeoff there which is secondary to ram. For units which fit inside the processor cache (MEGA is borderline depending on exact CPU) ram isn't as important and core clock can play a bigger role.

time check!!! I'm seeing 30 more minutes from Puerto Rico.

The challenge will begin 20 June 2016 22:34 UTC and end 25 June 2016 22:34 UTC.

Hmm...
http://primes.utm.edu/primes/page.php?id=121815
Jumping the gun a bit?

To make sure I understand, you have a dual socket system with two of those Xeons. Looking at the task results, note the run time and CPU time are very different.

Is HT on or off? If HT is on, turn it off would seem easiest way to prevent performance problems. If HT is already off, I'm not sure what to do. It does seem like the system might be putting the work onto one CPU and not spreading it evenly. I have rarely seen similar (tasks are put on same core, while another is idle) and restarting usually sorts it. Ram performance shouldn't matter for MEGA as the Xeons have plenty of cache.

It looks like demand for MEGA is so high that I ended up getting an ESP unit... I noticed I had accidentally left "Send work from any subproject if selected projects have no work" set to "Yes". That has since been changed to "No".

See my updated response, two posts back.
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

I think I might know what caused the problem. Just a guess, but the timing seems about right.

During challenges, I reduce the number of tasks the server will send out to each host. Normally, we allow computers to have a cache of 320 tasks per core. Before a challenge starts, I reduce this to 8 tasks per core. Especially with challenges with short tasks, we don't want a few computers sucking out all the tasks faster than we can replenish them.

After the challenge starts, I usually gradually increase this limit back to the normal 320.

Last night, I forgot to restore the limit to its normal value, so this morning I corrected my mistake by setting the limit to 320.

All at once.

I didn't do it gradually, and I think that's the problem.

The load on the server from computers wanting to fill up their caches may have backed things up enough to cause temporary outages in memory.

I've left myself a note for next time to be more careful with this. Thanks for bringing this to my attention!

EDIT: There's in fact ample supporting evidence that this is indeed what happened. So mystery solved, and I know how to prevent this in the future.
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Thanks for the info!

Hyper is off. Yes, it's a dual Xeon. Restarted BOINC and no change.

I think I might know what caused the problem. Just a guess, but the timing seems about right.

I think I might know what caused the problem. Just a guess, but the timing seems about right.

I don't understood well when it happened according to your scenario, but I had same issue as OP and it happened right at the start of the challenge on one of PCs. No problem for me (had "Send any work" disabled from the beginning), just hit "Update" once again when noticed. But it happened.

This is the number of MEGA tasks sent out at the beginning of the challenge, by minute:

+------+--------+----------+ | hour | minute | count(*) | +------+--------+----------+ | 22 | 33 | 138 | | 22 | 34 | 1373 | | 22 | 35 | 1405 | | 22 | 36 | 1237 | | 22 | 37 | 896 | | 22 | 38 | 656 | | 22 | 39 | 428 |

Challenge: Summer Solstice
App: 21 (PPS-Mega)
(As of 2016-06-22 00:28:56 UTC)

137331 tasks have been sent out. [CPU/GPU/anonymous_platform: 136827 (100%) / 0 (0%) / 504 (0%)]

Of those tasks that have been sent out:

1285 (1%) came back with some kind of an error. [1285 (1%) / 0 (0%) / 0 (0%)]
56184 (41%) have returned a successful result. [55752 (41%) / 0 (0%) / 433 (0%)]
79862 (58%) are still in progress. [79791 (58%) / 0 (0%) / 71 (0%)]

Of the tasks that have been returned successfully:

21049 (37%) are pending validation. [20867 (37%) / 0 (0%) / 183 (0%)]
34994 (62%) have been successfully validated. [34745 (62%) / 0 (0%) / 249 (0%)]
31 (0%) were invalid. [31 (0%) / 0 (0%) / 0 (0%)]
110 (0%) are inconclusive. [109 (0%) / 0 (0%) / 1 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is n=3534185. The leading edge was at n=3485907 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 1.38% as much as it had prior to the challenge!

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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Two primes have been found so far during the challenge. This does not include the prime found by Scott Brown hours before the challenge started.

This is the first one: 329*2^3518451+1, found by 288larsson.

The second one will be announced later.
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

It's mine!!!!!!!

This is turning out to be quite a lucky challenge. After a bit more than a day and a half, it looks like we've found three mega primes. (The third one hasn't been made public yet. It was just discovered and I'm in the process of verifying it as well as testing for for XGFN divisors.)
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Congratulation to Van Zimmerman for discovering the third mega-prime of the challenge!

351*2^3545752+1
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Me and the Number Crunchers Team have been running the PPSMega but forgot to sign up here. I have already found 2 numbers this week that appear to be prime because they've taken over a day to validate. Can I still enter?

Challenge: Summer Solstice
App: 21 (PPS-Mega)
(As of 2016-06-22 22:41:15 UTC)

204283 tasks have been sent out. [CPU/GPU/anonymous_platform: 203362 (100%) / 0 (0%) / 921 (0%)]

Of those tasks that have been sent out:

2557 (1%) came back with some kind of an error. [2557 (1%) / 0 (0%) / 0 (0%)]
114154 (56%) have returned a successful result. [113298 (55%) / 0 (0%) / 856 (0%)]
87572 (43%) are still in progress. [87507 (43%) / 0 (0%) / 65 (0%)]

Of the tasks that have been returned successfully:

39240 (34%) are pending validation. [38926 (34%) / 0 (0%) / 314 (0%)]
74677 (65%) have been successfully validated. [74136 (65%) / 0 (0%) / 541 (0%)]
98 (0%) were invalid. [98 (0%) / 0 (0%) / 0 (0%)]
139 (0%) are inconclusive. [138 (0%) / 0 (0%) / 1 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is n=3557811. The leading edge was at n=3485907 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 2.06% as much as it had prior to the challenge!
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

If any of those new primes turn out to divide some F(m), GF(m,b), or xGF(m,a,b), will you submit a comment to the entry linked (on Caldwell's site), or will we have to wait for the official PrimeGrid announcement?

Including the as yet unannounced fifth mega prime, we've found as many mega primes this week (actually, the last three days) as we did in all of 2013.

It's also more mega primes than we found in all of 2010, or any single year before that.
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Congratulation to RNDr. MF1 for discovering 381*2^3563676+1, our fourth prime of the challenge and the fifth PPS-MEGA prime this week!
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Including the as yet unannounced fifth mega prime, we've found as many mega primes this week (actually, the last three days) as we did in all of 2013.

Another prime:

309*2^3577339+1, discovered by Russ. Congratulations!

Our total number of mega primes since Monday (6) now ties the most mega primes in a single month, set this past February.
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Challenge: Summer Solstice
App: 21 (PPS-Mega)
(As of 2016-06-24 03:35:03 UTC)

286357 tasks have been sent out. [CPU/GPU/anonymous_platform: 284774 (99%) / 0 (0%) / 1583 (1%)]

Of those tasks that have been sent out:

4418 (2%) came back with some kind of an error. [4418 (2%) / 0 (0%) / 0 (0%)]
190466 (67%) have returned a successful result. [189072 (66%) / 0 (0%) / 1396 (0%)]
91473 (32%) are still in progress. [91285 (32%) / 0 (0%) / 187 (0%)]

Of the tasks that have been returned successfully:

53558 (28%) are pending validation. [53143 (28%) / 0 (0%) / 417 (0%)]
136450 (72%) have been successfully validated. [135473 (71%) / 0 (0%) / 977 (1%)]
218 (0%) were invalid. [218 (0%) / 0 (0%) / 0 (0%)]
240 (0%) are inconclusive. [238 (0%) / 0 (0%) / 2 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is n=3586341. The leading edge was at n=3485907 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 2.88% as much as it had prior to the challenge!
____________
Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Still no results back from one of my numbers from 3 days ago. Wonder why? All of my others were valid almost immediately.

Challenge: Summer Solstice
App: 21 (PPS-Mega)
(As of 2016-06-24 22:12:28 UTC)

339415 tasks have been sent out. [CPU/GPU/anonymous_platform: 337215 (99%) / 0 (0%) / 2200 (1%)]

Of those tasks that have been sent out:

8771 (3%) came back with some kind of an error. [8770 (3%) / 0 (0%) / 1 (0%)]
240126 (71%) have returned a successful result. [238070 (70%) / 0 (0%) / 2056 (1%)]
90519 (27%) are still in progress. [90376 (27%) / 0 (0%) / 143 (0%)]

Of the tasks that have been returned successfully:

57273 (24%) are pending validation. [56690 (24%) / 0 (0%) / 583 (0%)]
182230 (76%) have been successfully validated. [180758 (75%) / 0 (0%) / 1472 (1%)]
314 (0%) were invalid. [313 (0%) / 0 (0%) / 1 (0%)]
309 (0%) are inconclusive. [309 (0%) / 0 (0%) / 0 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is n=3599999. The leading edge was at n=3485907 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 3.27% as much as it had prior to the challenge!

With about 10 hours to go, it's time for the usual end of challenge reminder:

At the Conclusion of the Challenge

We would prefer users "moving on" to finish those tasks they have downloaded, if not then please ABORT the WU's instead of DETACHING, RESETTING, or PAUSING.

ABORTING WU's allows them to be recycled immediately; thus a much faster "clean up" to the end of a Challenge. DETACHING, RESETTING, and PAUSING WU's causes them to remain in limbo until they EXPIRE. Therefore, we must wait until WU's expire to send them out to be completed.
____________
Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

It looks like there is six primes found :)
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271643232^¹³¹⁰⁷²+1 GENERALIZED FERMAT :)
93*10^^1029523-1 REPDIGIT PRIME
31*332^³⁶⁷⁵⁶⁰+1 CRUS PRIME
Proud member of team Aggie The Pew. Go Aggie!

It looks like there is six primes found :)

Can you tell me exact start point on MEGA project?
Thanks
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271643232^¹³¹⁰⁷²+1 GENERALIZED FERMAT :)
93*10^^1029523-1 REPDIGIT PRIME
31*332^³⁶⁷⁵⁶⁰+1 CRUS PRIME
Proud member of team Aggie The Pew. Go Aggie!

Can you tell me exact start point on MEGA project?
Thanks

Final statistics:

Challenge: Summer Solstice
App: 21 (PPS-Mega)
(As of 2016-06-25 22:38:01 UTC)

423586 tasks have been sent out. [CPU/GPU/anonymous_platform: 420076 (99%) / 0 (0%) / 3510 (1%)]

Of those tasks that have been sent out:

40590 (10%) came back with some kind of an error. [40552 (10%) / 0 (0%) / 38 (0%)]
307945 (73%) have returned a successful result. [304599 (72%) / 0 (0%) / 3346 (1%)]
74714 (18%) are still in progress. [74598 (18%) / 0 (0%) / 116 (0%)]

Of the tasks that have been returned successfully:

55287 (18%) are pending validation. [54521 (18%) / 0 (0%) / 748 (0%)]
251839 (82%) have been successfully validated. [249262 (81%) / 0 (0%) / 2595 (1%)]
474 (0%) were invalid. [473 (0%) / 0 (0%) / 1 (0%)]
345 (0%) are inconclusive. [343 (0%) / 0 (0%) / 2 (0%)]

Thank you all for an absolutely tremendous challenge! Participation was amazing, but the really impressive statistic is, of course, the number of primes that were found. Six! Absolutely amazing. Great job everyone, and congratulations to the six of you on discovering a mega prime!!!
____________
Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

I expect the cleanup to take 2 to 4 weeks.

Cleanup status:
Jun-25: Summer Solstice: 55441 tasks outstanding; 46330 affecting individual (295) scoring positions; 29872 affecting team (62) scoring positions.
Jun-26: Summer Solstice: 43311 tasks outstanding; 36060 affecting individual (295) scoring positions; 21139 affecting team (57) scoring positions.
Jun-27: Summer Solstice: 22617 tasks outstanding; 16505 affecting individual (280) scoring positions; 7224 affecting team (44) scoring positions.
Jun-28: Summer Solstice: 14896 tasks outstanding; 10084 affecting individual (262) scoring positions; 4629 affecting team (36) scoring positions.
Jun-29: Summer Solstice: 10904 tasks outstanding; 6764 affecting individual (249) scoring positions; 2967 affecting team (29) scoring positions.
Jun-30: Summer Solstice: 5487 tasks outstanding; 3004 affecting individual (192) scoring positions; 499 affecting team (19) scoring positions.
____________
Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

Cleanup status:

Jun-25: Summer Solstice: 55441 tasks outstanding; 46330 affecting individual (295) scoring positions; 29872 affecting team (62) scoring positions.
Jul-1: Summer Solstice: 1845 tasks outstanding; 434 affecting individual (97) scoring positions; 44 affecting team (8) scoring positions.
Jul-2: Summer Solstice: 965 tasks outstanding; 173 affecting individual (51) scoring positions; 12 affecting team (2) scoring positions.
Jul-3: Summer Solstice: 652 tasks outstanding; 88 affecting individual (33) scoring positions; 1 affecting team (1) scoring positions.
Jul-4: Summer Solstice: 422 tasks outstanding; 39 affecting individual (21) scoring positions; 1 affecting team (1) scoring positions.
Jul-5: Summer Solstice: 121 tasks outstanding; 8 affecting individual (6) scoring positions; 1 affecting team (1) scoring positions.
Jul-6: Summer Solstice: 47 tasks outstanding; 5 affecting individual (4) scoring positions; 0 affecting team (0) scoring positions.
Jul-7: Summer Solstice: 17 tasks outstanding; 2 affecting individual (2) scoring positions; 0 affecting team (0) scoring positions.
Jul-8: Summer Solstice: 13 tasks outstanding; 2 affecting individual (2) scoring positions; 0 affecting team (0) scoring positions.
Jul-9: Summer Solstice: 9 tasks outstanding; 1 affecting individual (1) scoring positions; 0 affecting team (0) scoring positions.
____________
Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898⁵²⁴²⁸⁸+1

With the cleanup done and stats updated, we can announce the top participants and teams.

Congratulations go to:
1 zunewantan
2 Scott Brown
3 tng*

And in the teams department we can find these at the top:
1 Aggie The Pew
2 Czech National Team
3 Sicituradastra.

Thanks for all the participation and hope to see you during the next challenge!
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PrimeGrid Challenge Overall standings --- Last update: From Pi to Paddy (2016)