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1) Message boards : Number crunching : Yuri's Night Challenge (Message 150088)
Posted 196 days ago by HomefarmProject donor
I hope this isn't too far off topic.
If possible and not too difficult to do, does anyone reckon treating CPU and GPU stats for the same sub-project in 'Tasks returned in last 24 hours' as 2 separate items?

Hi Yes I think it would make tracking tasks easier.
2) Message boards : Fermat Divisor Search : Fermat Divisor Search (Message 149222)
Posted 233 days ago by HomefarmProject donor
Seems to be about 11k per day and about 70-75k left to do?

The number is on front page and it's 52K now. So it look promising. There are some tasks currently in progress but you should look at number of front page - when it reaches zero, project will run out tasks and we can consider it done (some timed out / resent tasks will be eventually available, and final cleanup can take many days, but most of time there will be no more DIV tasks).

OK Thanks for that. I should have thought of looking at the available tasks.

Here's hoping for a quick finale.
3) Message boards : Fermat Divisor Search : Fermat Divisor Search (Message 149218)
Posted 233 days ago by HomefarmProject donor
Happy to help try and knock this over before the SoB challenge.

Looks tight to get it completed before SoB.

Seems to be about 11k per day and about 70-75k left to do?

All hands to the pumps! I'm managing about 200+ per day, with AP on the GPUs.
4) Message boards : Number crunching : PrimeGrid Years (Message 148394)
Posted 263 days ago by HomefarmProject donor
1.833333333 yrs

22 months
5) Message boards : Number crunching : Tour de Primes 2021 (Message 148021)
Posted 270 days ago by HomefarmProject donor
Also I have another question, primes reported within the timeframe will all count, right? Not just primes whose tasks were sent after 2.1 00:00UTC?


It's when you discover the prime that counts, i.e., when your computer returns the task to the server. When it's reported to T5K does not matter. It does not matter when the task was sent to you.

To be clear, because it was not obvious to me even after reading this, it means that you CAN bunker LLR2 tasks before the start of the challenge.

With TdP and running CPU and GPU tasks together the control to split types of tasks, needed to give bunkers to give an advantage.

This is different from all the other challenges. So everyone who didn't connect the dots like me is already behind.

Bunkering will work for LLR2 reporting, but PPSE and GFN tasks will suffer as they are still DC tasks? The prime find might be lost to the wingman.
6) Message boards : Problems and Help : Help with finding primes (Message 147974)
Posted 272 days ago by HomefarmProject donor
HI Michael, May I offer my own suggestion, as I started here nearly 2 years ago, with little idea of how to proceed, and have become "addicted".

I keep exact records of run times for each sub project I run, for each PC and GPU type. It really shows you where you get good credits, for the input you make.

The higher yielders, as mentioned below will get you started and keep you interested as well. It's great fun to read the messages and see the opinions, you'll learn a lot here from very smart people (not me ;-))

Try SGS, PPSE, GFN15, GFN 16. You'll get primes and then you can study the "harder ones too"

Best wishes and good luck.

PS The Tour de Primes from 1st Feb might yield you a prime or two and some good badges.
7) Message boards : Generalized Fermat Prime Search : Guessing the future of GFN-22 and DYFL (Message 147096)
Posted 304 days ago by HomefarmProject donor
Given that a 3090 can run GFN22 in about 14 hrs, but DYFL will run in about 15.5 hrs, which sub project would you choose and which is more "likely" to have a chance of a prime, however remote?
8) Message boards : Generalized Fermat Prime Search : Genefer 3.3.5 is live! (Message 146243)
Posted 324 days ago by HomefarmProject donor
GFN-16 CPU tasks, my timings.

I9 10980XE 18 tasks concurrent 710 secs, equivalent 39 secs / task

3950X 16 tasks concurrent 611 secs, equivalent 38 secs / task

3090 GPU single task 48 secs running in 3950X with Pcie 4 SSD timing.

Timings vary of course, these are example results.
9) Message boards : Wieferich and Wall-Sun-Sun Prime Search : WW project is live (Message 146049)
Posted 328 days ago by HomefarmProject donor
it helps, Thank You ...

I have a question, why there is ... difference between finds and primes ... ???

regards, Grzegorz Roman Granowski ...

Hi Grzegorz,

Every prime number in the test range for each task is tested to see if it is a Wieferich and/or Wall-Sun-Sun prime. For each prime there is a calculation performed which results in a remainder in almost all cases. In the cases where the remainder is equal to zero then we have found a Wieferich or a Wall-Sun-Sun prime, but sometimes the remainder will be very close to zero, and those cases are interesting as well, so those will be counted as "finds". The find in this case is still a prime number, but the prime number itself is fairly small and not interesting; it is the property of that prime that is interesting.

On average, the remainder will be half of the prime being tested (so in the case of a test at 88P, the average remainder will be 4.4 x 1016, and the chances of a prime being a Wieferich or a Wall-Sun-Sun prime is 1/p, so 1 in 8.8 x 1016 at 88P depth. They are extremely rare, which is why it is interesting when the remainder is small. The probability of the remainder being within 10 of zero is still only 1 in 4.4 x 1015 at 88P depth.

Earlier I wrote an example of the math performed for the Wieferich search that may help understand it a bit more. The Wieferich search is looking for prime numbers that, when squared, divide evenly into 2p-1-1. The smallest know example of this is 1093. 10932 divides 21092-1 evenly, leaving no remainder.

These numbers are pretty big, so I have a better example with a different base, but same concept.

In this case the base is 3 instead of 2, and the prime is 11 instead of 1093.

310-1 = 59048
112 = 121
59048 divided by 121 is 488 and there is no remainder, so 3 and 11 make a Wieferich pair in base 3.

Wall-Sun-Sun is more complex than this, but a lot of the same probabilities apply :)


Kellen, thank you, that's very helpful to a non-mathematical brain like mine. As long as I count my cows I'm pretty happy LoL.

However I very much enjoy the team spirited search and competition in the PG projects. Excellent stuff!
10) Message boards : Number crunching : Rtx 30 series (Message 145300)
Posted 344 days ago by HomefarmProject donor
GFN 22 Same GPU as DYFL below, and very similar timing.
I believe the 3000 series are low ability on FP64 (?)


Workunit 681452482
Created 16 Nov 2020 | 10:09:27 UTC
Sent 17 Nov 2020 | 3:20:37 UTC
Received 17 Nov 2020 | 17:20:35 UTC
Server state Over
Outcome Success
Client state Done
Exit status 0 (0x00000000)
Computer ID 978470
Report deadline 9 Dec 2020 | 4:20:37 UTC
Run time 50,251.96
CPU time 586.98
Validate state Initial
Credit 0.00
Application version Genefer 22 v3.21 (OCLcudaGFNWR)
Stderr output
geneferocl 3.3.3-2 (Windows/OpenCL/32-bit)

Copyright 2001-2018, Yves Gallot
Copyright 2009, Mark Rodenkirch, David Underbakke
Copyright 2010-2012, Shoichiro Yamada, Ken Brazier
Copyright 2011-2014, Michael Goetz, Ronald Schneider
Copyright 2011-2018, Iain Bethune
Genefer is free source code, under the MIT license.

Running on platform 'NVIDIA CUDA', device 'GeForce RTX 3090', vendor 'NVIDIA Corporation', version 'OpenCL 1.2 CUDA' and driver '456.71'.
82 computeUnits @ 1695MHz, memSize=24576MB, cacheSize=2296kB, cacheLineSize=128B, localMemSize=48kB, maxWorkGroupSize=1024.
Supported transform implementations: ocl ocl2 ocl3 ocl4 ocl5

Command line: projects/ -boinc -q 182870^4194304+1

Normal priority change succeeded.
Checking available transform implementations...
A benchmark is needed to determine best transform, testing available transform implementations...
Testing OCL transform...
Testing OCL2 transform...
Testing OCL3 transform...
Testing OCL4 transform...
Testing OCL5 transform...
Benchmarks completed (17.343 seconds).
Using OCL5 transform
Starting initialization...
Initialization complete (52.324 seconds).
Testing 182870^4194304+1...
Estimated time for 182870^4194304+1 is 13:30:00
182870^4194304+1 is complete. (22071026 digits) (err = 0.0000) (time = 13:57:12) 17:20:29
17:20:29 (18160): called boinc_finish(0)


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