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Old 2022-07-13, 14:52   #21
P90 years forever!
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Aug 2002
Yeehaw, FL

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Originally Posted by lycorn View Post
I didn´t quite understand why you wrote there´s no point in using B2 > ~1000B1.
Any idea/recommendation/suggestion for exponent size and/or bounds?
If you use B2=100*B1, prime95 should select a close-to-optimal B2 (if there aren't any bugs)

The best B2 value is determined by shortest time to complete the "t" level you are working on.
Say, you are working on t70. Run gmp-ecm to get the number of curves required for the three different B2 values you tried (I think it is the -v switch). Compute prime95-runtime * number of curves required. The B2 with the smallest total runtime is the winner.

Please report back your findings. My 1000*B1 guesstimate was based on the rapidly diminishing returns for larger and larger B2 multipliers.
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