20160531, 17:56  #144  
"Mark"
Apr 2003
Between here and the
2×53×61 Posts 
Quote:


20160601, 02:53  #145 
Romulan Interpreter
"name field"
Jun 2011
Thailand
2650_{16} Posts 
Oooo! It pleases me to see Romanian names there! It means some people still do serious things in that country... (assuming he is not already in a western place, like a university or famous company already).
Congratulations mate! 
20160601, 18:31  #146  
Sep 2002
Database er0rr
3934_{10} Posts 
Quote:
Code:
time ~/coding/gwnum/s2 Pi_613373 1 Likely prime! real 600m23.209s user 392m46.660s sys 0m4.616s Last fiddled with by paulunderwood on 20160601 at 18:33 

20160601, 19:03  #147 
"Mark"
Apr 2003
Between here and the
14502_{8} Posts 
After making some changes to the assembler code to not return data, I have been able to get pixsieve to work on Windows and OS X. You can download the source and Windows executable from here.
The lmin option now works correctly and restarting from a preexisting file should work as well, although it requires the i option for the index file. I'll eventually eliminate that and let it use the pfgw file as the only input. A few caveats. First, it fails on OS X with O2, but will run correctly with O1. I have an idea why, but I haven't investigated yet. Since the vast majority of time is spent in the asm code, there won't be much of a gain between O1 and O2. Second, multithreading does not work on OS X. I suspect this is a problem in the use of semaphores. OS X has deprecated POSIX semaphores and uses what it calls a "dispatch semaphore". It is possible that I did not code that correctly. Third, it still fails to eliminate some composite numbers in the sieve. I don't know how many, but if it fails to eliminate them, then it might also be eliminating prime numbers. Nevertheless even with the caveats it is better than trying to factorize with pfgw and I know that it should eliminate 97% to 98% of the terms for many inputs fairly quickly. I intend to eventually replace the sieving and threading code, but I don't know when I'm going to do that because that will be a lot more work. Last fiddled with by rogue on 20160601 at 19:04 
20160602, 17:01  #148 
Sep 2013
2^{3}×7 Posts 
Indeed it does not eliminate all composite factor candidates, I still
get lines like p=13509635, 1.351M p/sec, 187 terms left, 13.5% done p=35525635, 2.200M p/sec, 178 terms left, 35.5% done Missing prime FCs: there is probably something going on with how work is split up multithreaded. I did some dozen runs with sPi1M.txt S110 l15K L20K P1e8 t1 always returns 135 terms remaining, missing a composite divisible by 14177 t2, t3, t4 return either 134 or 135, sort of random t7 returns something between 134 and 193 t15 always 135 'Always' means, in at least 6 test with this thread number I didn't see anything else. But, unless it doesnt sort PRPs into the factored file, I dont mind much if there is a composite slipping through occasionally  still way faster than PFGWTF! Thanks a lot! 
20160602, 17:33  #149 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
3·1,979 Posts 
How hard would it be to design a sieve that would sieve any ABC/ABC2 file?

20160602, 19:03  #150  
"Mark"
Apr 2003
Between here and the
2×53×61 Posts 
Quote:
Last fiddled with by rogue on 20160602 at 19:05 

20160602, 19:04  #151 
"Mark"
Apr 2003
Between here and the
2·53·61 Posts 

20160602, 20:24  #152 
Sep 2013
2^{3}×7 Posts 
Factor removal rate? *perk up* Sounds interesting  with known PRPtest
runtimes I can probably use that to determine a better TF depth. 
20160602, 20:30  #153 
"Mark"
Apr 2003
Between here and the
1100101000010_{2} Posts 
I have posted 2.0 here. 1.2 is still available, for now. There are a number of differences from 1.2 as this framework for this version is completely different. For example you run with this pixsieve P1e10 l2000 L3000 C20000 oterms.out spi.txt t4 S15. i is now used only for input when continuing a sieve, although I know that isn't working yet. Without i, it will start a new sieve. o is the output file that you use with pfgw. C is new. Use that to tell the program how many chunks of primes each thread will get. The default is 5000, but you will want to play around with it to get optimal performance. The r option is gone. The reporting time is 30 seconds. F will output the factors to pixsieve.log The output file (right now) is only written upon ^C or reaching the end of the sieve.
Here is an example with the input and output: Code:
/pixsieve P1e8 l20000 L30000 C20000 oterms.out spi.txt t4 S15 pixsieve v2.0, a CPU program to find factors of substrings of decimal string Sieve started: (cmdline) 0 <= p < 100000000 with 2770 terms 1028569  15926535897932384626 . . . 24874754031617969941 (23005 digits) 2170583  15926535897932384626 . . . 79470269232297186832 (20386 digits) . . . more factors . . . 56660377  15926535897932384626 . . . 66461900010350049018 (29467 digits) p=53533511, 100.9K p/sec, 2438 factors found at 0 secs/factor, 3.65 CPU cores, 53.5% done. ETA 02 Jun 15:18 64140539  15926535897932384626 . . . 89106524570802447493 (26469 digits) . . . more factors . . . 85822097  15926535897932384626 . . . 07248172987637569816 (20618 digits) 90358069  15926535897932384626 . . . 20599850235828918336 (28575 digits) Sieve complete: 0 <= p < 100000000 6001455 primes tested Clock time: 57.64 seconds at 104119 p/sec. Factors found: 2445 Processor time: 210.24 sec. (0.10 init + 210.14 sieve). CPU utilization: 3.65 (cores) 325 terms written to terms.out BTW, I fixed the issue with optimization not working on OS X. All I can say is that I find x86 assembly confusing and annoying to work with. Not being an expert means that I don't fully understand what some instructions will do. 
20160602, 21:09  #154 
Sep 2013
70_{8} Posts 
Cool toy!
Note: v2.0 complained 3 DLLs missing (libgcc_s_seh1, libstdc++6 and libwinpthread1  someting MinGWish?). I could use the ones from my SMPlayer (portable, so no DLLs registered systemwide) Don't know how common these are on a nonprogrammers machine, static link might be better for others who want to use this too. 
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