Welcome to PrimeGrid's 16th Birthday Challenge



The fourth challenge of the 2021 Series will be a 5-day challenge celebrating the 16th anniversary of the launch of PrimeGrid on BOINC. The challenge will be offered on the ESP-LLR application, beginning 12 June 13:00 UTC and ending 17 June 13:00 UTC.

On 12 June 2005, at approximately 14:00 UTC, Message@Home (now PrimeGrid) opened account creation to 50 users. It was being run on Rytis’ home laptop. Message@Home was developed as a test project for PerlBOINC, an attempt to implement the BOINC server system in the Perl programming language. As such, a project was needed that provided a short WU with a standard consistent result. The first was Message7, and it attempted by “brute-force” to recover a message encoded with the md5 algorithm.

On September 1st, 2005, after a short contest to select a new project name, the PrimeGrid name was chosen from a variation of PrimeGrid@Home submitted by Heffed. He was awarded 999 cobblestones for his submission.

One year later, in June 2006, dialog started with Riesel Sieve to bring their project to the BOINC community. Rytis provided PerlBOINC support and RS was successful in implementing their sieve as well as a prime finding (LLR) application. With collaboration from RS, PrimeGrid was able to implement the LLR application in partnership with another prime finding project, Twin Prime Search. In November 2006, the TPS LLR application was officially released at PrimeGrid, and the rest is history! (no really, there's so much more than I could fit here and it's fascinating! check out the link for more.)

To participate in the Challenge, please select only the Extended Sierpinski Problem LLR (ESP) project in your PrimeGrid preferences section.

Note on LLR2 tasks: LLR2 has eliminated the need for a full doublecheck task on each workunit, but has replaced it with a short verification task. Expect to receive a few tasks about 1% of normal length.

Application builds are available for Linux 32 and 64 bit, Windows 32 and 64 bit and MacIntel. Intel and recent AMD CPUs with FMA3 capabilities (Haswell or better for Intel, Zen-2 or better for AMD) will have a very large advantage, and Intel CPUs with dual AVX-512 (certain recent Intel Skylake-X and Xeon CPUs) will be the fastest.

Note that LLR is running the latest AVX-512 version of LLR which takes full advantage of the features of these newer CPUs. It's faster than the previous LLR app and draws more power and produces more heat, especially if they're highly overclocked. If you have certain recent Intel Skylake-X and Xeon CPUs, especially if it's overclocked or has overclocked memory, and haven't run the new AVX-512 LLR before, we strongly suggest running it before the challenge while you are monitoring the temperatures.

Multi-threading is supported and IS recommended. (ESP tasks on one CPU core will take 2-3 days on fast/newer computers and 1 week+ on slower/older computers.)

Those looking to maximize their computer's performance during this challenge, or when running LLR in general, may find this information useful.

• Your mileage may vary. Before the challenge starts, take some time and experiment and see what works best on your computer.
  
• If you have a CPU with hyperthreading or SMT, either turn off this feature in the BIOS, or set BOINC to use 50% of the processors.
  
  
  • If you're using a GPU for other tasks, it may be beneficial to leave hyperthreading on in the BIOS and instead tell BOINC to use 50% of the CPU's. This will allow one of the hyperthreads to service the GPU.

  
  

• The new multi-threading system is now live. Click here to set the maximum number of threads. This will allow you to select multi-threading from the project preferences web page. No more app_config.xml. It works like this:
  
  
  • In the preferences selection, there are selections for "max jobs" and "max cpus", similar to the settings in app_config.
    
  • Unlike app_config, these two settings apply to ALL apps. You can't chose 1 thread for SGS and 4 for SoB. When you change apps, you need to change your multithreading settings if you want to run a different number of threads.
    
  • There will be individual settings for each venue (location).
    
  • This will eliminate the problem of BOINC downloading 1 task for every core.
    
  • The hyperthreading control isn't possible at this time.
    
  • The "max cpus" control will only apply to LLR apps. The "max jobs" control applies to all apps.

  
  

• If you want to continue to use app_config.xml for LLR tasks, you need to change it if you want it to work. Please see this message for more information.
  
• Some people have observed that when using multithreaded LLR, hyperthreading is actually beneficial. We encourage you to experiment and see what works best for you.

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 at the very top, above the countdown clock.

Scoring Information

Scores will be kept for individuals and teams. Only tasks issued AFTER 12th June 2021 13:00 UTC and received BEFORE 17th June 2021 13:00 UTC will be considered for credit. We will be using the same scoring method as we currently use for BOINC credits. 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.

At the Conclusion of the Challenge

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

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

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

About the Extended Sierpinski Project

Wacław Franciszek Sierpiński (14 March 1882 - 21 October 1969), a Polish mathematician, was known for outstanding contributions to set theory, number theory, theory of functions and topology. It is in number theory where we find the Sierpinski problem.

Basically, the Sierpinski problem is "What is the smallest Sierpinski number" and the prime Sierpinski problem is "What is the smallest 'prime' Sierpinski number?"

First we look at Proth numbers (named after the French mathematician François Proth). A Proth number is a number of the form k*2^n+1 where k is odd, n is a positive integer, and 2^n>k.

A Sierpinski number is an odd k such that the Proth number k*2^n+1 is not prime for all n. For example, 3 is not a Sierpinski number because n=2 produces a prime number (3*2^2+1=13). In 1962, John Selfridge proved that 78,557 is a Sierpinski number...meaning he showed that for all n, 78557*2^n+1 was not prime.

Most number theorists believe that 78,557 is the smallest Sierpinski number, but it hasn't yet been proven. In order to prove it, it has to be shown that every single k less than 78,557 is not a Sierpinski number, and to do that, some n must be found that makes k*2^n+1 prime.

The smallest proven 'prime' Sierpinski number is 271,129. In order to prove it, it has to be shown that every single 'prime' k less than 271,129 is not a Sierpinski number, and to do that, some n must be found that makes k*2^n+1 prime.

Should both of these problems be solved, k = 78557 will be established as the smallest Sierpinski number, and k = 271129 will be established as the smallest prime Sierpinski number. However, this would not prove that k = 271129 is the second provable Sierpinski number. Since the prime Sierpinski problem is testing all prime k's for 78557 < k < 271129, all that's needed is to test the composite k's for 78557 < k < 271129. Thus, the Extended Sierpinski Problem is established.

The following k's remain for each project:

• Waclaw Franciszek Sierpinski (WIKI)
  
• Sierpinski number / The Sierpinski problem (WIKI)
  
• The Sierpinski problem (Prothsearch)
  

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
  

What is LLR2?

LLR2 is an improvement to the LLR application developed by our very own Pavel Atnashev and stream. It utilizes Gerbicz checks to enable the Fast DoubleCheck feature, which will nearly double the speed of PrimeGrid's progress on the projects it's applied to. For more information, see this forum post.
____________

Time flies like an arrow. Fruit flies like a banana.

39 hours in -- here are the stats!

Challenge: PrimeGrid's 16th Birthday
App: 20 (ESP-LLR)
Fast DC tasks are NOT included.
(As of 2021-06-14 03:52:54 UTC)

19933 tasks have been sent out. [CPU/GPU/anonymous_platform: 19933 (100%) / 0 (0%) / 0 (0%)]

Of those tasks that have been sent out:

1999 (10%) were aborted. [1999 (10%) / 0 (0%) / 0 (0%)]
74 (0%) came back with some kind of an error. [74 (0%) / 0 (0%) / 0 (0%)]
3389 (17%) have returned a successful result. [3389 (17%) / 0 (0%) / 0 (0%)]
14471 (73%) are still in progress. [14471 (73%) / 0 (0%) / 0 (0%)]

Of the tasks that have been returned successfully:

1122 (33%) are pending validation. [1122 (33%) / 0 (0%) / 0 (0%)]
2267 (67%) have been successfully validated. [2267 (67%) / 0 (0%) / 0 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (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=19221006. The leading edge was at n=18547400 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 3.63% as much as it had prior to the challenge!
____________

Time flies like an arrow. Fruit flies like a banana.

On a 3900x, 2x 6 core tasks seems to be quite a bit better with ESP than 4x 3 core tasks. On most projects it seems to be the opposite.

The 3900x has 4 CCX, thus 3 cores each who share 16 MB of L3 cache between them.

So the L3 steps to consider should be 5.3 MB (per core) and 16 MB (per CCX).
____________
1281979 * 2^485014 + 1 is prime ... no further hits up to: n = 5,700,000

3 days in, here are the workunit stats:

Challenge: PrimeGrid's 16th Birthday
App: 20 (ESP-LLR)
Fast DC tasks are NOT included.
(As of 2021-06-15 05:32:25 UTC)

27969 tasks have been sent out. [CPU/GPU/anonymous_platform: 27969 (100%) / 0 (0%) / 0 (0%)]

Of those tasks that have been sent out:

4006 (14%) were aborted. [4006 (14%) / 0 (0%) / 0 (0%)]
117 (0%) came back with some kind of an error. [117 (0%) / 0 (0%) / 0 (0%)]
7730 (28%) have returned a successful result. [7731 (28%) / 0 (0%) / 0 (0%)]
16116 (58%) are still in progress. [16115 (58%) / 0 (0%) / 0 (0%)]

Of the tasks that have been returned successfully:

2490 (32%) are pending validation. [2491 (32%) / 0 (0%) / 0 (0%)]
5240 (68%) have been successfully validated. [5240 (68%) / 0 (0%) / 0 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (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=19450736. The leading edge was at n=18547400 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 4.87% as much as it had prior to the challenge!
____________

Time flies like an arrow. Fruit flies like a banana.

And is it just me, or does the birthday cake banner only have 15 candles?

You observe correctly but, as discussed on Discord, the candles count from 0, & the 0th one isnt shown :).

On the 3900X (and similar) it is interesting. I don't have one, but based on architecture it is close to the line of 2 or 4 tasks being optimal. The tasks are 1920k FFT, so in theory will fit one per CCX. But as I've observed before, it isn't a clear switch at the boundary. There is a gradual transition starting a bit before, ending a bit after. Maybe unit variations or other factors can push it one way or the other.

On Intel there isn't the CCX business to worry about. Some random timings if anyone is interested. One task using all cores. Rounded to nearest kilosecond.

14ks i9 7920X (mobo seems to run this at or close to base clock)
18ks i7 11700k at 125W power limit
25ks E5 2683v3 ES (ES has lower clock than final version)
28ks i7 8086k at 95W power limit

4 days in and one to go! Updates:

Challenge: PrimeGrid's 16th Birthday
App: 20 (ESP-LLR)
Fast DC tasks are NOT included.
(As of 2021-06-16 15:27:47 UTC)

36492 tasks have been sent out. [CPU/GPU/anonymous_platform: 36492 (100%) / 0 (0%) / 0 (0%)]

Of those tasks that have been sent out:

8538 (23%) were aborted. [8538 (23%) / 0 (0%) / 0 (0%)]
158 (0%) came back with some kind of an error. [158 (0%) / 0 (0%) / 0 (0%)]
14294 (39%) have returned a successful result. [14294 (39%) / 0 (0%) / 0 (0%)]
13502 (37%) are still in progress. [13502 (37%) / 0 (0%) / 0 (0%)]

Of the tasks that have been returned successfully:

2969 (21%) are pending validation. [2969 (21%) / 0 (0%) / 0 (0%)]
11325 (79%) have been successfully validated. [11325 (79%) / 0 (0%) / 0 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (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=19597880. The leading edge was at n=18547400 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 5.66% as much as it had prior to the challenge!
____________

Time flies like an arrow. Fruit flies like a banana.

A few hours left in the challenge! Some friendly reminders... :)

At the Conclusion of the Challenge

When the challenge completes, we would prefer users "moving on" to finish those tasks they have downloaded, if not then please ABORT the WU's (and then UPDATE the PrimeGrid project) 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.

Likewise, if you're shutting down the computer for an extended period of time, or deleting the VM (Virtual Machine), please ABORT all remaining tasks first. Also, be aware that merely shutting off a cloud server doesn't stop the billing. You have to destroy/delete the server if you don't want to continue to be charged for it.

Thank you!
____________

Time flies like an arrow. Fruit flies like a banana.

Ahh got one in 2 minutes before the finish line. Got me 11 positions.
____________
My lucky number is 6219*2^3374198+1

And we're done! Final stats below. Cleanup tasks are now available.

Challenge: PrimeGrid's 16th Birthday
App: 20 (ESP-LLR)
Fast DC tasks are NOT included.
(As of 2021-06-17 15:04:19 UTC)

43035 tasks have been sent out. [CPU/GPU/anonymous_platform: 43035 (100%) / 0 (0%) / 0 (0%)]

Of those tasks that have been sent out:

13546 (31%) were aborted. [13546 (31%) / 0 (0%) / 0 (0%)]
208 (0%) came back with some kind of an error. [208 (0%) / 0 (0%) / 0 (0%)]
19058 (44%) have returned a successful result. [19058 (44%) / 0 (0%) / 0 (0%)]
8670 (20%) are still in progress. [8670 (20%) / 0 (0%) / 0 (0%)]

Of the tasks that have been returned successfully:

2473 (13%) are pending validation. [2473 (13%) / 0 (0%) / 0 (0%)]
16585 (87%) have been successfully validated. [16585 (87%) / 0 (0%) / 0 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (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=19698687. The leading edge was at n=18547400 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 6.21% as much as it had prior to the challenge!
____________

Time flies like an arrow. Fruit flies like a banana.

Since the challenge started, the leading edge has advanced 6.21% as much as it had prior to the challenge!

The page of ESP stats appears to be frozen in time. I don’t think the numbers on it have changed in a few days. Is it broken?

https://www.primegrid.com/stats_esp_llr.php
____________

The page of ESP stats appears to be frozen in time. I don’t think the numbers on it have changed in a few days. Is it broken?

https://www.primegrid.com/stats_esp_llr.php

The page of ESP stats appears to be frozen in time. I don’t think the numbers on it have changed in a few days. Is it broken?

https://www.primegrid.com/stats_esp_llr.php

Everything is OK. Leading edge is frozen because we have lot of aborted / resent tasks queued after the challenge. Only number of completed / inprogress task changes sometimes.

Cleanup Status:
Jun 18: 1629 tasks outstanding; 974 affecting individual (179) scoring positions; 565 affecting team (36) scoring positions.
Jun 19: 484 tasks outstanding; 196 affecting individual (84) scoring positions; 171 affecting team (12) scoring positions.
Jun 20: 427 tasks outstanding; 158 affecting individual (74) scoring positions; 153 affecting team (11) scoring positions.
Jun 21: 89 tasks outstanding; 20 affecting individual (18) scoring positions; 9 affecting team (1) scoring positions.
Jun 22: 53 tasks outstanding; 13 affecting individual (12) scoring positions; 6 affecting team (1) scoring positions.
Jun 23: 42 tasks outstanding; 9 affecting individual (9) scoring positions; 6 affecting team (1) scoring positions.
Jun 24: 27 tasks outstanding; 7 affecting individual (7) scoring positions; 5 affecting team (1) scoring positions.
Jun 25: 20 tasks outstanding; 5 affecting individual (5) scoring positions; 5 affecting team (1) scoring positions.
____________

Time flies like an arrow. Fruit flies like a banana.

The results are final!

During these 5 days, we completed more than 19 thousand tasks. No new ESP primes were found, but our LLR output was still more than 10 times ESP's average at its height. As one of the less popular subprojects, this challenge really gave it a boost, advancing the absolute leading edge by more than 6%.

108 teams and 422 individuals participated in the Challenge.

Top Three Individuals:
1. NightCoffee
2. Pavel Atnashev
3. Skillz

Top Three Teams:
1. TeAm AnandTech
2. Antarctic Crunchers
3. SETI.Germany


The next Challenge is the 🆆🅾🆁🅻🅳 🅴🅼🅾🅹🅸 🅳🅰🆈 Challenge, which starts July 17. We hope to see you there! Thank you again to everyone. We appreciate your participation and hope you had fun!
____________

Time flies like an arrow. Fruit flies like a banana.