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2020-02-18, 23:14   #419
storm5510
Random Account

Aug 2009
U.S.A.

3×5×103 Posts

Below would be in insertion into my list:

Quote:
 98475*2^257090-1 is prime! (77397 decimal digits)
I was trying to run the same k with LLR on multiple machines. No more. Doing so only served to put things out of sequence.

 2020-02-19, 08:14 #420 kar_bon     Mar 2006 Germany 2×1,423 Posts There're several options to do: 1. Split your sieve file by hand/script into equal numbers of values over the n-range and run them on several machines. -> Higher n-values will last longer for LLR so the lowest should be done first -> machines are ending with LLR on a wide range 2. Split the sieve file into several with this script with candidates spreaded over the whole n-range -> compareable machines in speed should do the LLR almost the same time -> all done at almost same time 3. Setting up a local PRPnet server for several machines, for more info see here
2020-02-19, 12:20   #421
storm5510
Random Account

Aug 2009
U.S.A.

154510 Posts

Quote:
 Originally Posted by kar_bon There're several options to do: 1. Split your sieve file by hand/script into equal numbers of values over the n-range and run them on several machines. -> Higher n-values will last longer for LLR so the lowest should be done first -> machines are ending with LLR on a wide range 2. Split the sieve file into several with this script with candidates spreaded over the whole n-range -> compareable machines in speed should do the LLR almost the same time -> all done at almost same time 3. Setting up a local PRPnet server for several machines, for more info see here

98475*2^313624-1 is prime! (94416 decimal digits)

I don't understand the script, but this has given me an idea for something comparable. Just in another language. As you say, split the sieve into two equal size files and run them concurrently. As for as I can tell, my i5 HP can run at roughly 90% of what the i7 does with the console version of LLR. No so with other things, such as Prime95 with all its GUI code. I can sieve on my laptop. The "sr" programs do not work it hard at all. It just takes a bit longer.

Last fiddled with by storm5510 on 2020-02-19 at 12:24 Reason: Additional

 2020-02-22, 00:03 #422 storm5510 Random Account     Aug 2009 U.S.A. 154510 Posts k = 98475. Tested to n = 400,000. No new primes found. Continuing for quite some time to come...
 2020-02-22, 00:16 #423 VBCurtis     "Curtis" Feb 2005 Riverside, CA 52·173 Posts Monthly updates are plenty, or every 1M milestone. Updating us every 100k is overkill many times over, just like posting individual primes under 1M bits in size.
 2020-02-26, 17:32 #424 storm5510 Random Account     Aug 2009 U.S.A. 3×5×103 Posts Reserving k = 741. Nash = 5029. I did multiple searches in the forum with different criteria and found no results for this k.
 2020-02-26, 18:06 #425 VBCurtis     "Curtis" Feb 2005 Riverside, CA 52·173 Posts Try the No Prime Left Behind forum; they coordinate most (all?) of the k's from 301 to 1999.
2020-02-27, 13:29   #426
storm5510
Random Account

Aug 2009
U.S.A.

30118 Posts

Quote:
 Originally Posted by storm5510 Reserving k = 741. Nash = 5029. I did multiple searches in the forum with different criteria and found no results for this k.
This k has been reserved by NPLB since 2012. Obviously, I need to expand my search areas in the future...

2020-02-27, 13:55   #427
diep

Sep 2006
The Netherlands

677 Posts

Quote:
 Originally Posted by storm5510 This k has been reserved by NPLB since 2012. Obviously, I need to expand my search areas in the future...
I tried search exponent=733 some years ago until 4M.

If you interested you can reserve that one and continue there. If you so lucky you'll have a prime very quickly.

edit: did not finish search till 4M entirely.

Last fiddled with by diep on 2020-02-27 at 14:02

2020-02-27, 14:15   #428
diep

Sep 2006
The Netherlands

677 Posts

Quote:
 Originally Posted by storm5510 98475*2^313624-1 is prime! (94416 decimal digits) I don't understand the script, but this has given me an idea for something comparable. Just in another language. As you say, split the sieve into two equal size files and run them concurrently. As for as I can tell, my i5 HP can run at roughly 90% of what the i7 does with the console version of LLR. No so with other things, such as Prime95 with all its GUI code. I can sieve on my laptop. The "sr" programs do not work it hard at all. It just takes a bit longer.
Faster for you might be cllr64
i wrote a small C program to splitup sieve files converted from ABCD files into something which then writes newpgen format.

It loadbalances the sieve files.

Yet when you get to larger exponentsizes like some millions of bits you might want to use multiple threads as that trashes the cache less. For each type of CPU with its different sizes caches the number of threads that works great will be different.

Once you use multithreading you no longer want to use stand alone cllr64 as trashing the cache give bad performance for multithreading. Throughput is higher then if you keep within.

So example i'm testing now at 7.0+ M bits for k=69 with 4 threads.
If the other 4 cores i would run 4 processes cllr64 testing k=733 to finish until 4M that would be bad idea as then the cache gets trashed for the cllr64 testing k=69 with 4 threads. It suddenly is immensely slower then. From its current 28.8k seconds that could get even 132k seconds.

If i would want to finish k=733 i would need to stop all the multithreading CLLR64's and run at the 8 real cores this box has (2 socket Xeon L5420 - yeah i know old) then 8 times cllr64 to finish k=733 until 4M.

Throughput for that is faster as the Xeons have 8MB L2 cache or something like that.

2020-02-27, 14:17   #429
diep

Sep 2006
The Netherlands

67710 Posts

Here is that splitup program. Works both in linux where i use it as well as windows where i use it too. After you compiled it of course.
Attached Files
 splitup.zip (1.4 KB, 31 views)

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