Page 8 of 10 FirstFirst ... 45678910 LastLast
Results 281 to 320 of 386

Thread: P-1 factorer

  1. #281
    I love 67607
    Join Date
    Dec 2002
    Location
    Istanbul
    Posts
    752
    Yes, that's true, the problem exists for P4 only.

    It also works on AMD Athlon without any problem. But, to be honest, I do not want to give up 515 kp/sec for P-1 at the moment.

    Still, I think it would be nice if this bug is repaired. P-1 needs P4 power as well.

    Originally posted by Nuri
    Yes, it seems so. I've just tried on Athlon 2400, and it works fine.

    As far as I remember, it was mentioned somewhere that PIV is the most efficient machine for this task. Too bad if it actually is the case.

    I hope Louie can have the time to take a look at it.

  2. #282
    Moderator Joe O's Avatar
    Join Date
    Jul 2002
    Location
    West Milford, NJ
    Posts
    643
    Originally posted by Nuri
    Still, I think it would be nice if this bug is repaired. P-1 needs P4 power as well.
    I most heartily concur!
    Joe O

  3. #283
    Sieve it, baby!
    Join Date
    Nov 2002
    Location
    Potsdam, Germany
    Posts
    959
    My P4 does a P-1 test at 1.5 in < 45 minutes.
    I assume P4s are a quite important factor in P-1 factoring.

  4. #284
    Moderator Joe O's Avatar
    Join Date
    Jul 2002
    Location
    West Milford, NJ
    Posts
    643
    Posted in the coordination thread:
    Originally posted by Frodo42
    4930000 4935000 Frodo42 169 2.483284 3 [completed]

    5100000 5110000 Frodo42 317 5.049642 ? [reserved]

    I don't seem to have any problem for n>4980670 with ver. 1.1 on P4 .
    Let's everyone with PIVs please post the details of their machine and the point at which it seems to start failing.
    Joe O

  5. #285
    Moderator Joe O's Avatar
    Join Date
    Jul 2002
    Location
    West Milford, NJ
    Posts
    643
    Nuri, Did you actually compute 4980670, or is that the one that failed?
    Joe O

  6. #286
    I love 67607
    Join Date
    Dec 2002
    Location
    Istanbul
    Posts
    752
    I did. May be it was not clear, I had to emphesize.


    From reservation thread:

    Please replace

    4980000 4982000 Nuri 91 1.624419 ? [reserved]
    4982000 4990000 ? ???? ?.?????? ? [soon to be passed]

    with

    4980000 4980670 Nuri 28 0.295272 1 [completed]
    4980726 4990000 ? ???? ?.?????? ? [soon to be passed]

    PS: 4980670 is the upper limit for my P4.

  7. #287
    Moderator Joe O's Avatar
    Join Date
    Jul 2002
    Location
    West Milford, NJ
    Posts
    643
    I didn't want to miss any so I tried the interval 4980670 4981000 and the first one it tried was 4980670. I wasn't sure if the endpoint was included in the range or the start point. I know that Louie posted it somewhere But I haven't been able to find it. If you make your endpoint 4980700 and i make that my start point, then it won't look like a there is a gap between our ranges, and there should be no confusion.

    On another note, have you tried ranges way above 5000000? Frodo42 has posted that he has no difficulty with 5100000 5110000 on a PIV.
    Joe O

  8. #288
    Senior Member Frodo42's Avatar
    Join Date
    Nov 2002
    Location
    Jutland, Denmark
    Posts
    299
    My success might be because I use the Linux version?
    I have now done something like 15 tests at 5.1M, they take 1.5 times the time needed at 4.9M, with the same parameters, but thats probably because a factor counts that much more at this point, their probability of success is also somewhat higher.

  9. #289
    I love 67607
    Join Date
    Dec 2002
    Location
    Istanbul
    Posts
    752
    Originally posted by Joe O
    If you make your endpoint 4980700 and i make that my start point, then it won't look like a there is a gap between our ranges, and there should be no confusion.
    Sure, I agree with you. Of course that should be the case normally.
    Since that was a specific case, I wanted to post it that way at the first place to show the exact maximum n in the dat file that it can handle, and exact minimum n it fails to run (to make it clear where exactly the problem starts). But, I see it created some confusion on your side.
    Originally posted by Joe O
    On another note, have you tried ranges way above 5000000? Frodo42 has posted that he has no difficulty with 5100000 5110000 on a PIV.
    Yes, I tried many alternatives. It takes just a few seconds for the client to exit for those ranges, therefore it was very easy to try tens of them up to 20m in a couple of minutes per client version.

  10. #290
    Moderator Joe O's Avatar
    Join Date
    Jul 2002
    Location
    West Milford, NJ
    Posts
    643
    Originally posted by Nuri
    ecm.exe <n low> <n high> <factor depth> <factor value> (mem usage at local.ini) ==> exits starting at 4980726.
    I get the same behaviour on an ATHLON!
    Joe O

  11. #291
    Sieve it, baby!
    Join Date
    Nov 2002
    Location
    Potsdam, Germany
    Posts
    959
    Originally posted by Joe O
    Let's everyone with PIVs please post the details of their machine and the point at which it seems to start failing.
    It seems like everyone with the P4/Windows combination has the problem.
    Maybe someone can fire up a Knoppisx version and start teh P-1 factorer? (I won't be able to get to my PC in the next days...)

  12. #292
    what happened here?

    3 | 33661*2^4993368+1

    bounds 20000 140000 with 128 and 1.5
    Last edited by Keroberts1; 10-23-2003 at 08:48 AM.

  13. #293
    I ran the same test again and got nothing. Should i paly with the bounds, is there a factor that I'm just barely missing or is this just a bug.

  14. #294
    Moderator Joe O's Avatar
    Join Date
    Jul 2002
    Location
    West Milford, NJ
    Posts
    643
    Originally posted by Keroberts1
    I ran the same test again and got nothing. Should i paly with the bounds, is there a factor that I'm just barely missing or is this just a bug.
    Probably a bug. This has happened recently to Frodo42 , and one other time as well.
    Joe O

  15. #295
    same thing again

    now i have two

    3 | 33661*2^4993368+1
    3 | 10223*2^4993901+1

    Does anyone know wahts causes this?

  16. #296
    Senior Member Frodo42's Avatar
    Join Date
    Nov 2002
    Location
    Jutland, Denmark
    Posts
    299
    Does anyone know when we can expect Louie back, we kind'a need him as he probably also is the only one who can fix these bugs with the P-1 factorer.
    If he does not expect to be able to give some time to this project within a reasonable time perhaps it would be a good idea if someone else began looking at the source code for the P-1 factorer (not me I study physic's, not math's)

  17. #297
    i think it happened again except this time its

    49 | 21181*2^4995332+1

    Thats three in about a range of 2 thousand. Is anyone else getting this error this often? I don't know whats wrong with my computer, maybe its because i only use 128 MBs RAM Could someone tell me if there is something wrong with it happening this often. For now I'm stopping on my ranges done upto 4997000. I havent' foudn any factors but i have had that error thre times. I think I'd be better off putting all o my resources into sieving.

  18. #298
    Please check out my last post here and let me know if this is a good idea (should give a speed boost of 2x)
    Team Anandtech DF!

  19. #299
    Hater of webboards
    Join Date
    Feb 2003
    Location
    København, Denmark
    Posts
    205
    I'm having a little trouble reporting the last factor that I have found.

    261252098359999236987971694398316499 | 28433*2^5314225+1

    The factor is larger than 2^117 and the Sieve Result Submission page only accepts factors less than 2^64.

    Without the limit to the bias in the score calculation this factor would have scores around 2.3*10^25 points.

    I think a factor of that size calls for a couple of smilies:

  20. #300
    wow is that 36 digits?

    What is the upper limit of a factor size that can be found using the P-1 factorer?

    That ones a real trophy.

  21. #301
    Senior Member
    Join Date
    Jan 2003
    Location
    UK
    Posts
    479
    I assume you've tried submitting to

    http://www.seventeenorbust.com/largesieve/

  22. #302
    Hater of webboards
    Join Date
    Feb 2003
    Location
    København, Denmark
    Posts
    205
    Originally posted by MikeH
    I assume you've tried submitting to

    http://www.seventeenorbust.com/largesieve/
    Now I have. (I had completely forgotten about that page).

    Originally posted by Keroberts1
    wow is that 36 digits?
    That's what I counted it to.

  23. #303
    Senior Member
    Join Date
    Feb 2003
    Location
    Sweden
    Posts
    158
    Congratulations, but that factor isn't prime (Mr. Killjoy here).

    261252098359999236987971694398316499 =
    1695263162018308849 * 154107105146414851

  24. #304
    Senior Member
    Join Date
    Jan 2003
    Location
    UK
    Posts
    479
    Keep this up, and you'll make it into the record books

    http://www.loria.fr/~zimmerma/records/Pminus1.html

    Oh, and I might need to make some hasty changes to the sieve scoring, not sure if it can cope with displaying that many digits.

  25. #305
    Hater of webboards
    Join Date
    Feb 2003
    Location
    København, Denmark
    Posts
    205
    Just in case anyone is interested, here is the factorization of p-1:

    2*3*457*86491*8622413*13809557*9251514854849

  26. #306
    Senior Member
    Join Date
    Feb 2003
    Location
    Sweden
    Posts
    158
    But that's not really what the P-1 algorithm found. Rather it found two factors (simultaneously, since the bounds covered both):
    1695263162018308849-1:
    2^4 * 3^4 * 7^2 * 157 * 317 * 2237 * 239779
    and
    154107105146414851-1:
    2 * 3 * 5^2 * 17 * 37 * 3217 * 10271 * 49433

  27. #307
    Moderator ceselb's Avatar
    Join Date
    Jun 2002
    Location
    Linkoping, Sweden
    Posts
    224
    Very smooth indeed.

  28. #308
    Member
    Join Date
    Jan 2003
    Location
    Germany
    Posts
    36
    I was trying to redirect the output of sbfactor to a file with something like

    ./run.sh 5322000 5323000 > progress

    but there is nothing written to progress.

    The idea behind this is to start sbfactor at system startup, but later monitor it under kde with tail -f ...

    Can anybody help me with this?

  29. #309
    Hater of webboards
    Join Date
    Feb 2003
    Location
    København, Denmark
    Posts
    205
    Originally posted by rosebud
    I was trying to redirect the output of sbfactor to a file with something like

    ./run.sh 5322000 5323000 > progress

    but there is nothing written to progress.

    The idea behind this is to start sbfactor at system startup, but later monitor it under kde with tail -f ...

    Can anybody help me with this?
    I redirect both STDOUT and STDERR with

    ./sbfactor 5134000 5136000 45 1.5 512 > uddata 2>&1

    and that works.

  30. #310
    Senior Member Frodo42's Avatar
    Join Date
    Nov 2002
    Location
    Jutland, Denmark
    Posts
    299
    ./sbfactor 5134000 5136000 45 1.5 512 > uddata 2>&1
    I use 47 instead of 45 as 2^47=140.74*10^12 and the sieve 90% point has passed.
    As I understand this just makes sure that the P-1 factorer does not check for or find duplicates.

  31. #311
    Member
    Join Date
    Jan 2003
    Location
    Germany
    Posts
    36
    Originally posted by hc_grove
    I redirect both STDOUT and STDERR with

    ./sbfactor 5134000 5136000 45 1.5 512 > uddata 2>&1

    and that works.
    Well, I tried that, too, but it equally just creates an emtpy file, doesn't write anything into it.


    I use 47 instead of 45 as 2^47=140.74*10^12 and the sieve 90% point has passed.
    As I understand this just makes sure that the P-1 factorer does not check for or find duplicates.
    I thought about that, too, but it gives me lower bounds than with 45. Isn't it actually less likely to find factors with smaller bounds, especially when the sieving point goes up? So shouldn't be the bounds be increased instead? Please correct me if I'm wrong...

  32. #312
    Rosebud,
    run.sh invokes sbfactor. So you need to redirect the output of sbfactor. Try to edit run.sh and it should work.

  33. #313
    Member
    Join Date
    Jan 2003
    Location
    Germany
    Posts
    36
    Thanks for your help, I just found out, that I was just not patient enough.
    Apparently some buffer is written to the outputfile in 4kb blocks, I just didn't wait long enough to see it happen before I killed the program again.

  34. #314

    Errors in ECM

    I used version 11 dev.

    This is what I found.

    [Mon Dec 01 11:50:44 2003]
    ECM found a factor in curve #1, stage #1
    Sigma=7999200192601744, B1=2000, B2=200000.
    2956796616715477563801784791791170379265868824629460864415946527130271264717466812248233802997132847 5423878344513 | 265711*2^199920+1
    [Mon Dec 01 13:21:36 2003]
    ECM found a factor in curve #1, stage #1
    Sigma=636312383509189, B1=2000, B2=200000.
    453696229622164192714306768330898875898888916174816736249304693155093236170413062337 | 265711*2^199920+1


    both the factors are wrong.

    k=265711 is being used on the PSP project.


    Citrix

  35. #315
    What is the limit on the size of a factor we could expect to find using P-1. Could we find a record factor? Very soon sieving will run past its usefullness and many sievers will probably be switching CPUs towards P-1. Or at least i will be. At the point we'll have a rather significant amount of CPU power running there. Just wondering what our chances are of hitting a record.

  36. #316
    Member
    Join Date
    Jan 2003
    Location
    Germany
    Posts
    36
    Hypothetical the maximum size is unlimited. But I think the odds of finding a record factor are pretty small. I run sbfactor with B1=30000 and B2=320000 which is what the bounds optimizer gives me.
    All record p-1 factors (40+ digits) where found using much higher bounds: B1 > 10^7, B2 > 10^8


  37. #317
    Hater of webboards
    Join Date
    Feb 2003
    Location
    København, Denmark
    Posts
    205
    Originally posted by rosebud
    Hypothetical the maximum size is unlimited. But I think the odds of finding a record factor are pretty small. I run sbfactor with B1=30000 and B2=320000 which is what the bounds optimizer gives me.
    All record p-1 factors (40+ digits) where found using much higher bounds: B1 > 10^7, B2 > 10^8
    But my 36 digit factor was found using B1=35000, B2=420000, so B1 and B2 doesn't have to be that big.

    Having said that, I do think my factor will be our largest for quite a while. Maybe MikeH should change the stats to show the 3 or 5 largest factors so others have a chance of having big factors recognized?

  38. #318
    I'm sorry but i thought tha had been found ot be a composite of two factors? Does that matter?

  39. #319
    Senior Member
    Join Date
    Feb 2003
    Location
    Sweden
    Posts
    158
    Yes, that matters. The reason hc_grove's bounds didn't need to be so high is that the bounds only had to be sufficient for a 19-digit factor (and an 18-digit one).

    The chance that a set of small factors completely factors a number decreases as the number gets bigger.

    And if you're aiming for a record I'm sure nothing but a prime factor is accepted.

  40. #320
    I love 67607
    Join Date
    Dec 2002
    Location
    Istanbul
    Posts
    752
    Are there any news on fixing the P-1 bug for PIVs?

    I am aware that it is not of top priority, but some feedback would be useful.

Page 8 of 10 FirstFirst ... 45678910 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •