Der sechste PrimeGrid Wettbewerb des Jahres 2018 findet als siebentägiges Rennen statt, während dessen das Cullen Prime Search (LLR) Projekt gerechnet wird.
(Ich erspare den geschätzten Lesern das Geseiere über das Oktoberfest, das im originalen Post vorhanden ist. Bitte lest es unten im englischen Original, falls es euch interessiert)
Um teilzunehmen, wählt nur die Cullen Prime Search LLR (CUL) Applikation aus den CPU-Projekten in den PrimeGrid Einstellungen aus. Der Wettbewerb wird am 15. September 2018, 18:00 UTC (20:00 Uhr MESZ) beginnen und am 22. September 2018 18:00 UTC enden.
Applikationen gibt es für Linux 32 und 64 Bit, Windows 32 und 64 Bit sowie MacIntel.
Intel CPUs mit AVX Befehlssatz (Sandy Bridge, Ivy Bridge, Haswell, Broadwell, Skylake, Kaby Lake, Coffee Lake) werden große Vorteile haben, und Intel CPUs mit FMA3 Befehlssatz (Haswell, Broadwell, Skylake, Kaby Lake, Coffee Lake) werden die schnellsten sein.
Ich möchte an dieser Stelle darauf hinweisen, daß es besonders für Kleincruncher, die nicht auf einen Platz in den vorderen 300 Rängen hoffen dürfen, attraktiv sein könnte, auf unseren Cluster-Account zu rechnen, um diesen nach oben zu pushen. Die derart errechneten Credits gehen in die Individualwertung des Cluster-Accounts sowie in die Teamwertung ein, nicht aber in eure eigene Individualwertung. Diese Credits verbleiben auch nach dem Wettbewerb beim Cluster-Account.
Ich bitte einen der Admins des Cluster-Accounts, dessen Weak Account Key für PrimeGrid in diesem Thread bekanntzugeben.
Welcome to the Oktoberfest Challenge!
The sixth Challenge of the 2018 Challenge series is a 7 day challenge to celebrate Oktoberfest. The challenge is being offered on the Cullen Prime Search (LLR) application.
Oktoberfest is the world's largest Volksfest (beer festival and travelling funfair). Held annually in Munich, Bavaria, Germany, it is a 16 to 18-day folk festival running from mid or late September to the first weekend in October, with more than six million people from around the world attending the event every year. Locally, it is often called the Wiesn, after the colloquial name for the fairgrounds, Theresa's meadows (Theresienwiese). The Oktoberfest is an important part of Bavarian culture, having been held since the year 1810. Other cities across the world also hold Oktoberfest celebrations that are modelled on the original Munich event.
During the event, large quantities of Oktoberfest Beer are consumed: during the 16-day festival in 2013, for example, 7.7 million litres (66,000 US bbl) were served. Visitors also enjoy numerous attractions, such as amusement rides, sidestalls, and games. There is also a wide variety of traditional foods available.
This year Oktoberfest will start on Saturday, September 22nd. The Schottenhamel tent will be the place to be if you want to catch the official opening ceremonies. At noon, the Mayor of Munich will have the honor of tapping the first keg of Oktoberfest beer. Once the barrel has been tapped, all visitors will then be allowed to quench their thirst. The festival will go until October 7th.
To participate in the Challenge, please select only the Cullen Prime Search LLR (CUL) project in your PrimeGrid preferences section. The challenge will begin 15th September 2018 18:00 UTC and end 22nd September 2018 18:00 UTC.
Application builds are available for Linux 32 and 64 bit, Windows 32 and 64 bit and MacIntel. Intel CPUs with AVX capabilities (Sandy Bridge, Ivy Bridge, Haswell, Broadwell, Skylake, Kaby Lake, Coffee Lake) will have a very large advantage, and Intel CPUs with FMA3 (Haswell, Broadwell, Skylake, Kaby Lake, Coffee Lake) will be the fastest.
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. Tasks on one CPU core will take ~2 days on fast/newer computers and 7+ days 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, Broadwell, Skylake, Kaby Lake or Coffee Lake (i.e., Intel Core i7, i5, and i3 -4xxx or better) computers running the application will see fastest times. Note that CUL is running the latest FMA3 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. If you have a Haswell, Broadwell, Skylake, Kaby Lake or Coffee Lake 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.
Multi-threading optimisation instructions
Those looking to maximise 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 an Intel CPU with hyperthreading, either turn off the hyperthreading 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.* Use LLR's multithreaded mode. It requires a little bit of setup, but it's worth the effort. Follow these steps:
* Create a app_config.xml file in the directory C:\ProgramData\BOINC\projects\www.primegrid.com\ (or wherever your BOINC data directory is located). For a quad core CPU, the file should contain the following contents. Change the two occurrences of "4" to the number of actual cores your computer has.
* After creating the file, click on "Options/Read config files". You should then restart BOINC or reboot.
* The first time BOINC downloads an CUL task, it may act a little strange and download 4 tasks instead of 1. The run times on this first set of tasks may look a bit strange too. This is normal. This will also occur anytime BOINC downloads more than one task at a time. This can be avoided by setting "Use at most [ 1 ] % of the CPUs" before you download CUL tasks. After one task was downloaded, increase the percentage.
* 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.
Scores will be kept for individuals and teams. Only tasks issued AFTER 15th September 2018 18:00 UTC and received BEFORE 22nd September 2018 18:00 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.About the Cullen Prime Search
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.
A Cullen number in the form of n*2^n+1. Fr. James Cullen first studied these numbers in 1905 because they have interesting divisibility properties. It is conjectured that there are infinitely many n values that will yield Cullen primes, though it has been shown that almost all are composite.
Cullen Number on Wikipedia
Cullen prime Prime Pages' Glossary entry
Top Twenty Cullen Primes in Chris Caldwell's Database
The following n values yield prime Cullen numbers (OEIS A005849) (ones found at Primegrid highlighted):
1, 141, 4713, 5795, 6611, 18496, 32292, 32469, 59656, 90825, 262419, 361275, 481899, 1354828, 6328548, and 6679881.
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:
Zitat von PrimeGrid, Übersetzung von Teilen sowie nicht extra gekennzeichnete Kommentare von mir.