20121120, 16:02  #12 
Tribal Bullet
Oct 2004
3489_{10} Posts 
CADO does not support GPUs; other researchers have substituted their own GPU components for the corresponding pieces in CADONFS (i.e. make the Block Weidemann code use a GPU for matrix multiplies).
It's an open question whether lowering the target norm makes it easier to find good hits; it certainly drastically reduces the number of hits found, and you would think that it would help the size optimization deal with the loworder coefficients if the top few polynomial coefficients were much smaller than average. But I don't know that, so far all the hits I've found have led to polynomials a lot worse than their current best one. Delivering big batches of hits isn't a problem; I can take them by email or you can upload to Rapidshare or some other online storage service if the results are more than a few megabytes compressed. Greg: I don't know how many hits we should look for. Nobody has ever done a massively parallel polynomial search, as in throwing BOINC at it for months. For RSA768 we spent three months and collected something like 15 million stage 1 hits, and the best resulting polynomial was just about as good as the one actually used for the sieving. For RSA896 the current code divides the search space for each leading coefficient into 46 pieces, so searching one of those only exhausts 2% of the available search space. A trillion hits would probably be too much to deal with, though it would be awesome :) 
20121120, 18:10  #13 
Jul 2003
So Cal
3^{2}·227 Posts 
What's the Murphy e of their current best?

20121120, 18:26  #14 
Tribal Bullet
Oct 2004
3·1,163 Posts 
4.8e19; Paul tells me that the best they expect is 20e19.

20121120, 19:35  #15 
Jul 2003
So Cal
2043_{10} Posts 
I ran stage 2 on a single core overnight, and the best was 1.704e19.

20121122, 19:05  #16 
Sep 2008
Kansas
2×1,567 Posts 
Thanks to Jason's help I've got a run started at 5*10^13.
It looks like I am getting around ten per minute in this range. Correction: Better than 25/min. (I can't divide...) Last fiddled with by RichD on 20121122 at 19:14 
20121123, 08:15  #17 
Jul 2003
So Cal
3^{2}·227 Posts 
Great minds think alike. I started one GPU at 10^13, same as Jason, and the second at 5*10^13, same as you.
So far it's done 10^13 to 10^13+2.5*10^8 with 131k hits and 5*10^13 to 5*10^13+3*10^8 with 152k hits. Last fiddled with by frmky on 20121123 at 08:18 
20121123, 19:17  #18 
Sep 2008
Kansas
110000111110_{2} Posts 
Update
Just over 24 hours I am approaching 38k but still just under
5*10^13 + 1*10^8. Last fiddled with by RichD on 20121123 at 19:18 Reason: typo 
20121128, 17:57  #19 
Nov 2010
2·5^{2} Posts 
I got 417K stage1 hits for
Code:
msieve np1 "stage1_norm=1e33 100000000000000,1000000000000000" 
20121129, 01:24  #20 
Tribal Bullet
Oct 2004
DA1_{16} Posts 
Maybe post to rapidshare or some similar storage hosting?

20121129, 14:42  #22 
Tribal Bullet
Oct 2004
3489_{10} Posts 
Okay. When running stage 2, you will save a lot of time if you first run with
nps "stage2_norm=1e100" so that only the size optimization runs for every hit. On my machine running the size optimization on the 250k hits I have took about 36 hours. Then sort the resulting .ms file in order of increasing score (which is the last field in each line) and just run msieve with npr on the few lines in the .ms file that have the smallest score, perhaps only the 1000 best hits. The root sieve runs faster with a tight bound on the stage 2 norm, so try npr "stage2_norm=1e37" or possibly smaller if that winds up taking too long. We've found that if you run all of stage 2 on every hit you spend the majority of the time running the root sieve on hits that will never generate very good polynomials, and the root sieve can take minutes for a single hit (where the size optimization takes half a second) 
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