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Old 2013-08-07, 23:27   #1
TheMawn
 
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Default Are Facts Double Checked?

I was just wondering about a GPU going bad while doing trial factoring and returning wrong results.

If a GPU incorrectly returns "No Factor Found" it will be a bit unfortunate, but not the end of the world.

If a GPU incorrectly returns "Factor Found", I assume it would be insanely easy to check if that is in fact a factor. Does any double checking happen? And how?
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Old 2013-08-07, 23:36   #2
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Have you ever tried to submit a "fake" factor?
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Old 2013-08-07, 23:41   #3
TheMawn
 
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No. Is it funny? Or do I get killed by a giant prime number?
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Old 2013-08-07, 23:49   #4
kracker
 
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Quote:
Originally Posted by TheMawn View Post
No. Is it funny? Or do I get killed by a giant prime number?
Is it funny? Maybe.
Do you get killed by a giant number? No.
What you do get is... nothing...nothing at all...absolutely nothing...
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Old 2013-08-07, 23:54   #5
TheMawn
 
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Oh good. I just tried to fake one. Blah not a factor of blah. Nothing too aggressive.
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Old 2013-08-08, 00:56   #6
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Quote:
Originally Posted by TheMawn View Post
If a GPU incorrectly returns "Factor Found", I assume it would be insanely easy to check if that is in fact a factor. Does any double checking happen? And how?
The PrimeNet server always double-checks any reported factor.
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Old 2013-08-08, 07:18   #7
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Quote:
Originally Posted by cheesehead View Post
The PrimeNet server always double-checks any reported factor.
Even if I report a jumbo factor for a number that already has a known smaller factor?
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Old 2013-08-09, 00:54   #8
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Quote:
Originally Posted by Uncwilly View Post
Even if I report a jumbo factor for a number that already has a known smaller factor?
This actually raises another older question of mine. Can mfaktc find multiple factors if there are more than one in the tested range? Do they all get through or does the server just care about the fact that one was found in the first place?
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Old 2013-08-09, 01:20   #9
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yes, this is in mfaktc/o !

Quote:
# possible values for StopAfterFactor:
# 0: Do not stop the current assignment after a factor was found.
# 1: When a factor was found for the current assignment stop after the
# current bitlevel. This makes only sense when Stages is enabled.
# 2: When a factor was found for the current assignment stop after the
# current class.
#
# Default: StopAfterFactor=1
i found too 2 factors in one assignment with StopAfterFactor 0.
of course you can find factors of a low bit level and again on a higher level.
but make it sense to search again on the same exponent on a high level if a factor is found on a low level ?

so setting 2 make more sense or not ?

Norman

Last fiddled with by NormanRKN on 2013-08-09 at 01:24
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Old 2013-08-10, 15:56   #10
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Certainly, 2 makes the most sense if you want it to stop as soon as possible after you find a factor. 0 makes the most sense if you want to find all the factors in range.

1 makes the most sense if you have stages turned on and turning in partially checked bit levels gives you mental hives.

I run 2, because I'm mostly just trying to rule out prime numbers.
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Old 2013-08-28, 10:13   #11
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What is generating results like these, with the results ordered by factor?
(Also, there were no no-factor results in between.)
I'm wondering because there's a huge range of exponents there, from 2M to 19M not counting the seperate bit at the bottom.
Is this a different algorithm being used for factoring or something? Because as cheesehead said the server double checks factors so they must be correct...?

http://pastebin.com/bULhTKwr
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