20121130, 12:53  #23 
Nov 2010
2×5^{2} Posts 
Stage 2 finished, the best 10 polynomials murphy_e ranges in 2.348e19  2.129e19. Not very impressing.
Last fiddled with by poily on 20121130 at 12:55 
20121130, 16:42  #24 
Tribal Bullet
Oct 2004
3·1,181 Posts 
I ran stage 2 on 250k hits computed by RichD and myself, the best evalue was 2.0e19, so not that great. Shi Bai ran the CADO stage 2 on the same dataset and has gotten better high scores (I think the best so far was 3.2e19)

20121130, 19:44  #25 
Basketry That Evening!
"Bunslow the Bold"
Jun 2011
40<A<43 89<O<88
3×29×83 Posts 
As I recall from past comparisons (B200?), msieve typically has a ~10% lower score due to your more sophisticated integrator. How much of that better score is due to the differences in integration?

20121201, 13:07  #26 
Tribal Bullet
Oct 2004
3×1,181 Posts 
I was going to write that most of the time the evalues calculated by the two suites differ by less than 1%, and larger differences were actually because of bugs in Msieve that miscalculated the alpha value. But then to make sure I ran the best CADO polynomial through Msieve, and the difference in evalues was 4.78e19 vs 3.493e19!
For the record, the best polynomial I could find in the batch of 260k hits was Code:
R0: 5876926706329267758590334567904669751467577 R1: 869332622169838859059 A0: 15018543190390770338953421520339801353757924940775872204660800 A1: 909208080136930262159142936022283921496280008021988680 A2: 13303473065609161166913597414184875440269406556 A3: 138145188131827120402436868843139274434 A4: 763752915545626483996372079531 A5: 4312543659621449260154 A6: 10000466830200 skew 133010468.05, size 3.823e020, alpha 12.788, combined = 2.080e019 rroots = 4 Last fiddled with by jasonp on 20121201 at 13:22 
20121201, 14:25  #27 
Nov 2010
62_{8} Posts 
Here's my slightly better (according to msieve) polynomial
Code:
SKEW 28338177.70 R0 3626941552197564826492128852700460060642852 R1 48957407582916194761589 A0 26101732745933806144485280988037796254029367990700826499285 A1 2408464141902741608017790242140644715688145388490381 A2 174314770228113076791419006080421369720970639 A3 28697722660097589508721192118263624637 A4 1036456362256909021188219944324 A5 21292410351587764080336 A6 181000001476800 skew 28338177.70, size 4.381e20, alpha 12.189, combined = 2.348e19 rroots = 2 Last fiddled with by poily on 20121201 at 14:27 
20121204, 09:59  #28 
Nov 2010
2·5^{2} Posts 
I got it by myself: CADO's E.sage gives 1.84701205471987e19 for your and 2.08696883313422e19 for my polynomial.

20121204, 12:19  #29 
Tribal Bullet
Oct 2004
3×1,181 Posts 
The difference is that the CADO tools compute the size score by integrating in radial coordinates, whereas Msieve starts in radial coordinates and switches to computing the integral in rectangular coordinates. They don't compute the same numbers in general.
Msieve uses the rectangular integral because pol51opt did, and the GGNFS scripts had a table of precomputed 'good' scores to shoot for. Nonetheless, the radial score is more robust for some reason, i.e. it finds a better minimum a lot of the time. 
20121205, 07:05  #30 
Jul 2003
So Cal
2223_{10} Posts 
Here are approx. 1.3 million stage 1 hits:
https://www.dropbox.com/s/spssx3ze8i...896_1.dat.m.gz Edit: I restarted the stage 1 search at different values. I'm now running the size optimization on this file now, and I will run the root sieve on those with the smallest score. Last fiddled with by frmky on 20121205 at 07:16 
20121205, 09:43  #31 
Nov 2010
2·5^{2} Posts 
So, the best murphy_e we have so far is about 2.5e16, I wonder how CADO guys got murphy_e 2x larger than ours? Either their polynomial is quite extraordinary or they use different optimization algorihtms.

20121205, 17:49  #32 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
1011100110001_{2} Posts 
Is it possible we should run msieve stage 2 on their stage 1 results or their stage 2 on our stage 1 results?

20121206, 03:00  #33 
Tribal Bullet
Oct 2004
3×1,181 Posts 
I don't have access to the CADO stage 1 hits. We've collected 2.7M hits of our own, and they will all have stage 2 performed by both packages.
Keep 'em coming! Ilya, I suspect a lot of the difference boils down to the more effective root sieve developed by Shi Bai for the CADO stage 2. From what I've seen it consistently produces better alpha scores without sacrificing as much polynomial size as Msieve needs. Last fiddled with by jasonp on 20121206 at 03:03 
Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Volunteers needed  axn  GPU Computing  28  20120528 12:05 
call for volunteers: RSA768 polynomial selection  jasonp  Operation Kibibit  200  20111105 21:31 
Call for help  Wacky  NFSNET Discussion  13  20050714 00:25 
Volunteers needed!  Xyzzy  Hardware  23  20030418 23:27 
We need two volunteers...  Xyzzy  PrimeNet  8  20030227 02:26 