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Old 2003-03-11, 18:10   #1
xtreme2k
 
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Default Factoring so slow??

I am going to run a LLtest of M33395827. However after 2 days of factoring (around 50 hours up to now, 80-85% cpu time - I am guessing here) prime still havent start to actual LL test. It has completed the initial trial factoring to 2^68 and currently its doing some 'Stage 1' thing and at around 65%.

The computer is a P4 2.4@3.1 with 2GB RAM, 1GB given to prime.
Is there something wrong or am I just being too impatient?
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Old 2003-03-11, 18:39   #2
garo
 
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Nothing's wrong. It takes about 2 days to do trial factoring to 68 bits and currently your machine is doing a P-1 test which goes in two stages. The LL test should start in another day or so - if P-1 does not find a factor.
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Old 2003-03-11, 18:47   #3
lycorn
 
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And also, as you have given 1GB to prime95, it can be anticipated a long time waiting for Stage 2 of P-1 to finish. The good point is that the chances of finding a factor are higher.
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Old 2003-03-11, 19:34   #4
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And if you find a factor, you have just eliminated a very expensive LL test (and the doublecheck!). This means you can move on more quickly to an exponent that just might yield that whopper of a prize.
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Old 2003-03-11, 19:47   #5
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Thanks for the response :)

Previously I have only been running Double checking on this system as it only takes a few days per test on those. Now I might want to give LL test ago see how things are :)
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Old 2003-03-11, 23:06   #6
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Quote:
Previously I have only been running Double checking on this system as it only takes a few days per test on those.
Just out of curiosity, how do your system take to complete a DC in the current range (9M)? I use a P4 1,6 for DCs and it takes me just over 4 days. I reckon in your system it should take half of it.
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Old 2003-03-12, 04:44   #7
xtreme2k
 
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Quote:
Originally Posted by lycorn
Quote:
Previously I have only been running Double checking on this system as it only takes a few days per test on those.
Just out of curiosity, how do your system take to complete a DC in the current range (9M)? I use a P4 1,6 for DCs and it takes me just over 4 days. I reckon in your system it should take half of it.
Yah it used to take about two and a half days for each LL test on the 9M range. Each iteration time is around 0.016sec.
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Old 2003-03-13, 04:12   #8
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Which is a lot of the difference - the 33M+ range takes a lot longer, and the iteration time is also a lot slower.

Even on a P4.

9-)
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