factoring request
in [Math]
|
Prev: Typography: Choosing Century Expanded?
Next: Considering the forces of computation: questions for the group, I have three:
From: dan73 on 29 Nov 2009 04:13 >> This was already factored --- > >> See "more on factoring floor(pi*(10^111)) >> posted on 16th nov. >> Dan >Ah ok. You took a significant time but is normal with >ECM when a factor is of this size. I guess so, 3.10 sec. against 14 days. I must live in the dinosaur age. It would probably be much faster with ECM if my cp was a duo core processor and I downloaded the ECM software instead of doing it online! Probably more like 10 days. Even at that, 3.10 sec. really makes that look sick. What are the bench-marks with 60-80 digit composites with GGNFS and ECM when the two factors are of equal length in these composites. Dan Dan
From: factorboy13 on 30 Nov 2009 21:11 > > I guess so, 3.10 sec. against 14 days. > I must live in the dinosaur age. > Well, not 3.10 sec, actually 3 hours and 10 minutes :( And I did it with a i7 860 working with 8 threads! > What are the bench-marks with 60-80 digit composites > with GGNFS and ECM when the two factors are of equal > length in these composites. GGNFS is not the best for factors up to 100 digits, probably SIQS is better when factors are about equal size and ECM can not find fast a factor up to 30 digits
From: dan73 on 30 Nov 2009 22:32 > I guess so, 3.10 sec. against 14 days. > I must live in the dinosaur age. > >Well, not 3.10 sec, actually 3 hours and 10 minutes :( >And I did it with a i7 860 working with 8 threads! >> What are the bench-marks with 60-80 digit composites >> with GGNFS and ECM when the two factors are of equal >> length in these composites. >GGNFS is not the best to factor numbers with up to 100 >decimal digits, probably SIQS is better when factors >are about equal size and ECM can not find fast a factor >up to 30 to 35 digits What does that mean in real time for just one computer factoring floor(pi*(10^111))because when I see 8 threads does that mean you had 8 other processors as help? I like to experiment with different factoring methods but to be quite honest a lot of these factoring algorithms are way over my head. Thanks for the info! Dan
From: factorboy13 on 30 Nov 2009 23:19 i7 processors are quad-core but each core can run 2 threads. This makes it sort of eight-core. Since ggnfs+msieve allow to allocate CPUs and Threads to a job then i was running at full speed (near 100% CPU utilization). My operating system is Windows 7 64-bit and have used the 64-bit binaries of the software. A Pentium 4 3.0 would probably be much slower, at least 1 day to factor that number with the same software.
From: Pubkeybreaker on 1 Dec 2009 10:35
On Dec 1, 8:32 am, dan73 <fasttrac...(a)att.net> wrote: > I like to experiment with different factoring methods > but to be quite honest a lot of these factoring > algorithms are way over my head. Ignorance is a curable disease. Run, don't walk, and get a copy of: Crandall & Pomerance, Prime Numbers, A computational Perspective. Read it. It will teach you all about modern factoring methods. It is an excellent book. |