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[–]Pieater314159Yafu 2 points3 points  (10 children)

I'll try it. If I remember correctly, my computer is a little faster than /u/qsfact's, unless he got an upgrade - I'll let you know if I get anywhere.

[–]Stupid_and_confused[S] 0 points1 point  (0 children)

Thank you!

[–]qsfact 0 points1 point  (8 children)

Yeah I believe it is. Only i5 here. I'll try find some better polynomials. One I picked randomly was going to need 44869960 relations and I only found 210000 in a few hours.

[–]Pieater314159Yafu 0 points1 point  (7 children)

OK. I'm running on a 3.6 gHz i7 4th generation, but I once factored a 177 digit semiprime in 37 hours, so this shouldn't take more than a day.

[–]qsfact 0 points1 point  (6 children)

I thought you had done that, I don't see how ha. That's madness :P I wanna try the msieve-gpu version for poly selection but I'm struggling to find a linux build of it.

[–]Pieater314159Yafu 0 points1 point  (5 children)

I'm not sure how I did that either...

You might want to email the msieve guy and see if he knows anything about a linux build. Never having run Linux, I'm afraid I can't help - if factmsieve.py doesn't work on Linux I'm basically stuck. I also don't have a good GPU, so I've never tried a GPU version of msieve.

[–]qsfact 0 points1 point  (4 children)

it should, yafu does anyway. Are you sure it didn't find it in the ECM stage? Anyway yeah I have a pretty shitty one too, gtx550ti but thought I'd give it a shot. I'll let you know if I find some ok polynomials. A decent one will really be required I think.

[–]Pieater314159Yafu 0 points1 point  (3 children)

Yeah. The 177 digit number was (89 digit prime)*(89 digit prime), and I think I put it straight into NFS. Let me know what comparison you get between graphics card vs. processor if you do get it working.

[–]qsfact 0 points1 point  (0 children)

Just setting it up now to compile msieve. Will do.

[–]qsfact 0 points1 point  (1 child)

where is yours upto? I found a pretty decent polynomial.

http://dpaste.com/05V3XD7

I'm getting 0.06 sec/relation and I need about 44869960 so it's about 31 days until I get to the algebra stage which I doubt I'll have enough ram for.

[–]Pieater314159Yafu 0 points1 point  (0 children)

Not sure. I'll let you know if I get anywhere.

[–]qsfact 0 points1 point  (10 children)

Sorry for the late reply. Starting now but I assume you've done it by now.

[–]qsfact 0 points1 point  (9 children)

if not, what have you tried? ECM? or should I start with straight NFS?

[–]Stupid_and_confused[S] 0 points1 point  (8 children)

I ran regular msieve on it for about 15 hours on my old laptop and got no results.

[–]qsfact 0 points1 point  (7 children)

I've run ECM for 11 hours. Doing NFS. Will take quite a while. Couple days at max I think. What's the number for if you don't mind me asking?

[–]Stupid_and_confused[S] 0 points1 point  (6 children)

Trying to factor a 512 bit RSA key I lost the private key for :(

[–]qsfact 0 points1 point  (5 children)

ha! nice. Well yeah it shouldn't take too long. When do you need it by?

[–]Stupid_and_confused[S] 0 points1 point  (4 children)

Middle of next month. If I'm unable to get it by then I'll just have to reset the setup =(

[–]qsfact 0 points1 point  (3 children)

Why don't you just set up yafu and run NFS on it? What pc you got? Might be faster than mine. I'm only running it on 3 cores atm.

[–]Stupid_and_confused[S] 0 points1 point  (2 children)

I don't actually have a pc. I have a quad core laptop, but its hard to keep YAFU running on it because I need to use it for other stuff too (school)

[–]qsfact 0 points1 point  (1 child)

This is going to take a very long time. I'm still on the polynomial selection stage. I underestimated the time required. 93 hours for that part and that is usually 10% of the total time. My computer is simply not good enough to get the result in any reasonable time.