PrimeGrid Challenges 2021

[crashtech]

Is GFN-17-Low worth running on CPU?

 

[Skillz]

I will be utilizing mostly CPU power to run them myself.

 

[Skivelitis2]

I'll be all in with GPUs and CPUs with hyper-threading off. Not gonna take the time to set up multi-threading via cc_config however.

 

[StefanR5R]

cpuGFN16, cpuGFN17LOW, cpuGFN17MEGA, cpuGFN18, cpuGFN19, cpuGFN20 are single-threaded applications (last time I checked — edit: this info is still up to date with the current app versions). Only cpuGFN21 can and should be used with multiple threads per task.

Edit, I thought about setting up an offline test for cpuGFN[17LOW] for comparison tests with a fixed workunit, but haven't had the spare time yet.

 

[Skivelitis2]

Thanks for that Stefan! Must be thinking of the old LLR app before Michael Goetz(?) set up multi-threading in the project prefs. Glad I didn't waste my time.

 

[crashtech]

My informal look at performance with a GTX 1070 vs 2x E5-2690v4 CPUs showed that the CPUs did not do badly. With no HT, 28 threads were finishing a task every ~3 minutes*, while the GPU was finishing a task every ~7 minutes or so. Based on this admittedly non-rigorous info, I will run everything except AMD GPUs and pre-Haswell CPUs for the 72 hour run, and only stop anything if it proves to be underperforming.

*Each thread was taking ~5000 seconds to complete a WU, but overall effect with 28 going is 1 every ~3 minutes.

 

[Ken g6]

We're off! Wow, it feels like a long time since we did one of these.

 

[Skillz]

@Pokey I noticed you're helping us with the Challenge. Thanks! May I make a suggestion?

Set all your BOINC instances to only store .01 days worth of work and .01 additional days worth of work. That's 0.01 in both fields.

That way you don't download 100s of tasks at once. The reason for this is because if one of your WUs happen to be a Prime number and it's deep, deep in your queue then someone will most likely return it before you do and they'll get the credit for finding the Prime.

Setting it to .01 in both fields means you'll have 1 WU (sometimes 2) WUs per thread/core/GPU at a time and it wont build up a cache.

Due note, that Pendings do not matter here. They count all pendings towards the challenge; however should one of your pendings be invalid then it will deduct points from the scoreboard. This will happen during the challenge and after it's over.

 

[Pokey]

I have changed local computing prefs to 0.01 stored work + 0.01 additional work and clicked on "read local prefs file". If I understand this, it will still take a half day to chew through the present work load before these settings kick in. I don't want to abort the existing work so I will just let things ride, unless there is a compelling reason to do so??

 

[lane42]

Were in first place so far, Way to go Team
I will be adding 2 more computers today.

 

[Skillz]

Hey! I found a Prime!

PrimePage Primes: <span dir=ltr>26757382^131072 + 1</span>

This page contains information about a single prime (discoverer, verification data, submission dates...). This page is about the prime 26757382^131072+1.

primes.utm.edu

 

[Skillz]

I have changed local computing prefs to 0.01 stored work + 0.01 additional work and clicked on "read local prefs file". If I understand this, it will still take a half day to chew through the present work load before these settings kick in. I don't want to abort the existing work so I will just let things ride, unless there is a compelling reason to do so??

Hey! I found a Prime!

PrimePage Primes: <span dir=ltr>26757382^131072 + 1</span>

This page contains information about a single prime (discoverer, verification data, submission dates...). This page is about the prime 26757382^131072+1.

primes.utm.edu

This is your compelling reason to abort those tasks. lol

Aborting tasks isn't a bad thing. It immediately puts them back in the queue to be resent to crunchers.

On your account page, at PG, scroll towards the bottom. It should show you how many of your results are 1st and a percentage of results that are 1st out of all the ones you've done.

I suspect your % is pretty low, despite you having some pretty quick GPUs that return tasks fairly quickly.

 

[Pokey]

This is your compelling reason to abort those tasks. lol

I suspect your % is pretty low, despite you having some pretty quick GPUs that return tasks fairly quickly.

OK, it's done. My percentages were in the 35ish to 45ish% range before aborting the excess work. So let's see what this does.
Thanks

 

[StefanR5R]

I am way behind at the end of the top 30 myself — gonna have to switch on some more of my computers,

I reached the top 20. Just a matter of putting the better suited ones among my computers to the task. :-)

 

[Ken g6]

Day 1 stats:

Rank___Credits____Username
1______17809676___Skillz
8______3312332____Icecold
12_____2824068____Pokey
14_____2663177____crashtech
16_____2374884____xii5ku
34_____922349_____Orange Kid
47_____648923_____emoga
52_____579005_____biodoc
59_____530122_____Skivelitis2
90_____308236_____Lane42
117____208228_____Ken_g6
175____102576_____Fardringle
329____1784_______geecee

Rank__Credits____Team
1_____32275988___TeAm AnandTech
2_____21908319___Antarctic Crunchers
3_____21474797___SETI.Germany
4_____12213241___Czech National Team

Wow, @Skillz, seems like you overshot a little.

 

[Skillz]

Been a little over 1 day now.

Item	team	Points	Action
1	TeAm AnandTech	32,275,988.21	overview
2	Antarctic Crunchers	21,908,319.17	overview
3	SETI.Germany	21,474,797.71	overview
4th	Czech National Team	12,213,241.51	overview
5	Aggie The Pew	9,418,437.88	overview

The Team is kicking butt in first place with a commanding lead over the rest of the pack. Second place AC is just barely in front of SG. SG has turned on the boosters the last few hours and closed a decent gap on AC. Can SG keep their momentum and pass AC for 2nd?

Can TAAT break 100M in this challenge?
Will AC be able to hold onto second or will SG come out victorious?
Will ATP catch CNT for 4th?

#	Rank	User	Team	Credit​
1	1	Skillz	TeAm AnandTech​	17,809,676.61​
2	8	Icecold	TeAm AnandTech​	3,312,332.51​
3	12	Pokey	TeAm AnandTech​	2,824,068.65​
4	14	crashtech	TeAm AnandTech​	2,663,177.47​
5	16	xii5ku	TeAm AnandTech​	2,374,884.04​
6	34	Orange Kid	TeAm AnandTech​	922,349.59​
7	47	emoga	TeAm AnandTech​	648,923.51​
8	52	biodoc	TeAm AnandTech​	579,005.42​
9	59	Skivelitis2	TeAm AnandTech​	530,122.64​
10	90	Lane42	TeAm AnandTech​	308,236.24​
11	117	Ken_g6	TeAm AnandTech​	208,228.01​
12	175	Fardringle	TeAm AnandTech​	102,576.17​
13	329	geecee	TeAm AnandTech​	1,784.22​

The 13 members who have returned results. @Icecold has come from behind to land in 2nd place. While @Pokey and @crashtech battle for 3rd. Can't rule out @StefanR5R (xii5ku) who has been known to optimize his systems as the challenges progress. @Orange Kid is comfortably in 6th place. @emoga might want to keep an eye on his rearview mirror as @biodoc could have some tricks up his sleeve. @Skivelitis2 is gonna need to add more boxen to the race if he wants to catch biodoc or emoga. @lane42 rounds off the top 10, but shouldn't sleep comfortably with @Ken g6 behind him. @Fardringle is far behind the lead pack and someone should wake greecee up.



edit
Dang it @Ken g6 you beat me to it.

edit 2
Decimal representation of the prime number discovered by me.

Decimal representation for 26757382^131072+1

It's got 973,530 digits.

 

[Markfw]

It looks like you are way in the lead. If you get in a bad way, let me know, I can fire up a 7551 EPYC with 64 threads.

 

[Skillz]

It looks like you are way in the lead. If you get in a bad way, let me know, I can fire up a 7551 EPYC with 64 threads.

I'll keep that in mind, @Markfw but it looks like we will be fine for this challenge. Should AC or SG juice up some more power and we're in danger I'll give you a shout.

 

[Skillz]

I wonder if we can hit 100M in the challenge?

 

[lane42]

1​

Skillz

TeAm AnandTech

28 850 666.62​

64 639​

Well you might

 

[StefanR5R]

Can't rule out @StefanR5R (xii5ku) who has been known to optimize his systems as the challenges progress.

I actually used to determine the optimizations in a timely manner _before_ the challenges. Then went into a challenge prepared but just with a few computers without much heat and noise and hit on the power bill, then stepped it up later during the challenge when the need for speed became overwhelming. ;-)

More recently I find it more difficult to set aside the spare time for proper preparation. :-|

 

[Fardringle]

I don't normally participate in the PG events since I don't have any GPUs worth using for most races.

However, the GFN17 Low app seems to be running REALLY well on my Ryzen 3900X, so I'll let it work on the challenge whenever I'm not actively using the computer. None of my other computers even have graphics cards, and their CPUs are super crappy at this app so they'll keep doing other stuff.

In the meantime, I thought it was interesting to see that out of the 540 tasks that I have had completed and validated so far, 124 were done by the GTX 1060 and 416 were done by the Ryzen 3900X. That means the CPU is out-producing the GPU by a factor of 3.35 to 1. Don't see that happen very often.

Based on the actual run times, I estimate the 3900X could produce around 190K per day on this application if I didn't ever interrupt it. That's pretty impressive, actually. I was using the computer for other CPU intensive things more than half of the day yesterday, but I'll be at work all day for the next few days so it will probably get to run PG for about 20 out of 24 hours until the end of the challenge. That might move me out of 12th place before the end, but I'm not counting on it. I'll just enjoy seeing GPU type daily numbers out of the CPU..

 

[Ken g6]

Day 2 stats:

Rank___Credits____Username
1______36536503___Skillz
6______7891850____Icecold
7______7675961____crashtech
10_____6095827____xii5ku
15_____5123438____Pokey
36_____1797220____Orange Kid
41_____1583530____biodoc
63_____1023395____Skivelitis2
74_____814316_____emoga
84_____698072_____Lane42
121____408585_____Ken_g6
152____297150_____Fardringle
338____7147_______geecee

Rank__Credits____Team
1_____69944046___TeAm AnandTech
2_____46848572___SETI.Germany
3_____44429417___Antarctic Crunchers
4_____24915023___Czech National Team

@Skillz would be the third-place team! Without Skillz the rest of us would be the third-place team! Good job, everybody! One day to go.

 

[Skillz]

Did someone say I need to add more powa? More? I'm on it!

edit
In other news. I found another prime. My 2nd prime ever.

PrimePage Primes: 28294666^131072 + 1

This page contains information about a single prime (discoverer, verification data, submission dates...). This page is about the prime 28294666^131072+1.

primes.utm.edu

That badboy has 976,710 decimals.

edit 2
@crashtech found a prime also!

 

[lane42]

1​

TeAm AnandTech

97 340 463.61​

1​

TeAm AnandTech

100 108 794.89​

I wonder if we can hit 100M in the challenge?

Just about there