20091231, 09:09  #1 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
2×2,969 Posts 
PFGW vs LLR comparison discussion
i would be very interested in running some of the numbers that can be converted to base 2 as they run faster(how much faster now we have the new pfgw?)
however i am not certain that i am able to run a whole file within a short time period would loading some into a server be worthwhile? it could be a first test for the soon to be released version of prpnet 
20091231, 09:34  #2  
May 2007
Kansas; USA
3^{3}·17·23 Posts 
Quote:
To the best of my knowledge and experience, no, neither PFGW nor LLR will run base 16 faster than base 2. LLR knows to internally convert them, whether the conversion be for the base or for the kvalue. Two examples: 1. LLR would internally convert 2297*16^101 to 2297*2^401 to gain the faster testing speed of base 2. 2. LLR would internally convert 3620*16^101 to 3620*2^401 and from there convert it to 905*2^421 to gain both the faster testing speed of base 2 and a possible smaller fftlen and hence increased speed of the lower kvalue. In the results file, it will always display the test in base 2 and of the original kvalue, although it internally uses a reduced kvalue if it can to gain testing speed. You might check it out for yourself to confirm this. As far as I know, PFGW should not be used for any powerof2 base. LLR should always be at least as fast or faster. You can reserve a smaller file. Let me know if you want to reserve an n=500 or n=1000 file. If so, I'll split up the 1st file link. I'd prefer not to add and administer any more public servers until we get all of the NPLB servers on my machine, which will likely be in < 2 weeks after a friend finishes getting a couple of more machines built for me. (I just talked to him today and he's said he'll do it.) You might talk to Max about setting up a private server, which he can do on my machine. Gary Last fiddled with by gd_barnes on 20091231 at 09:38 

20091231, 09:53  #3 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
13462_{8} Posts 
I didnt make myself hugely clear like usual. I knew how LLR converted base 16 to base 2. My question about PFGW was how much longer does it take to test a nonbase 2 number(base 589 for example) of the same size than a base 2 number with LLR.
Once i have finished my 137 digit gnfs i will reserve a small file here. Last fiddled with by henryzz on 20091231 at 09:53 
20091231, 13:34  #4 
Mar 2006
Germany
2^{4}·3·61 Posts 
here is an example (on an i7 with 8 threads):
for 3051*2^4910001 LLR needs about 540s (about 148000 digits). in the same time PFGW do 2*1019^524001 (about 158000 digits). so for this example PFGW is slightly faster for the same amount of digits. 
20091231, 14:39  #5  
"Mark"
Apr 2003
Between here and the
14504_{8} Posts 
Quote:
In other words, if you want to compare apples to apples, then test run a test with both, but for the same base (and not base 2). My recommendation is that you use LLR for base 2 (and powers of 2) and PFGW for all other bases. 

20091231, 14:48  #6  
Mar 2006
Germany
2^{4}·3·61 Posts 
Quote:
Quote:
Last fiddled with by kar_bon on 20091231 at 14:49 

20091231, 15:54  #7 
"Mark"
Apr 2003
Between here and the
14504_{8} Posts 

20091231, 18:01  #8 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
2×2,969 Posts 
i thought someone would know the figures lol
i can work it out myself it just doesnt make sense if every single person does their own timing i was talking about prp and llr not primality tests cause those are used in general testing it is another thing that will have to wait until i am back on windows after my factorization going back to linux after adjusting back to windows is proving slightly wierd i have reaized that i was coping with an inferior operating system maybe linux is not in comparison with vista but it is in comparison with windows 7 IMO 
20100102, 08:08  #9 
May 2007
Kansas; USA
293D_{16} Posts 
Punctuation, capitalization, sentence breaks, and paragraph breaks please. Thanks.
I'm complaining because I answered the wrong question before. 
20100102, 08:14  #10  
May 2007
Kansas; USA
3^{3}·17·23 Posts 
Quote:
Perhaps someone should start an all around base 3 Riesel effort like RPS/NPLB for Riesel base 2. Base 3 would be far heavier weight for virtually all k's because nothing could be divisible by 3. It would be the reverse of base 2 in that you would search all even k's instead of all odd k's. Edit: I just thought of something: Karsten, you need to compare the same kvalue to make it an apples to apples comparison. Like LLR, PFGW is faster for smaller kvalues. Since your base 2 kvalue is much higher, that's probably why it's slower than the base 1019 test. I also wonder if the machine would need the 8 threads for PFGW to be as fast as LLR. Gary Last fiddled with by gd_barnes on 20100102 at 09:18 

20100102, 09:09  #11 
Jun 2006
Chertsey Surrey UK
2·179 Posts 
Now the cats out of the bag. :)
Everyone and his dog will be doing non base 2 work. I am surprised it took so long for the penny to drop. 
Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Comparison of NFS tools  CRGreathouse  Factoring  3  20180205 14:55 
APRCL implementations comparison  ldesnogu  Computer Science & Computational Number Theory  11  20151028 12:54 
Comparison Page Not Working  wblipp  Operation Billion Digits  0  20121124 06:33 
PFGW 3.3.6 or PFGW 3.4.2 Please update now!  Joe O  Sierpinski/Riesel Base 5  5  20100930 14:07 
Pollard's Algorithm & That of Devaraja comparison  devarajkandadai  Miscellaneous Math  22  20050610 11:13 