20051121, 02:23  #1 
Jun 2005
382_{10} Posts 
Question about factoring bounds
I just began factoring of a new Mersenne number, and noticed the following on th Prime95 output:
Ignoring suggested B1 value, using B1=395000 from the save file Ignoring suggested B2 value, using B1=4740000 from the save file What I had done prior to this was increase the memory usage because it said it was going to put off factoring because of memory availability. So did the program determine it should use larger bounds because of the available memory, but it got overridden by the formerly determined value? If so, isn't he newer value more appropriate? And why do these bounds get entered in the save file anyway if they're computed so quickly when factoring begins? Thank in advance for clearing this up for me. I'm a very curious person. Last fiddled with by drew on 20051121 at 02:33 
20051122, 00:53  #2  
"Richard B. Woods"
Aug 2002
Wisconsin USA
2^{2}·3·641 Posts 
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(IIRC, if only B2 were increased and B1 were unchanged, then Prime95 could just continue stage 2 from where it left off. But I may be mistaken about that.) Quote:
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(But I'm getting a headache from the bouncing whatzit.) 

20051122, 01:04  #3 
"Richard B. Woods"
Aug 2002
Wisconsin USA
1111000001100_{2} Posts 
Hmmm ... I see that my preceding answer assumed that your system had already done part of stage 2 before you changed the memory assignment.
But if it hadn't yet started stage 2, there would be no wastage. ... Probably the code just does what it does anyway in order to protect itself as described above, without taking into comsideration whether there's no wastage. I could give you a more definite answer if I perused the source code again, but your bouncing whatzit has given me such a headache that I couldn't concentrate if I did that perusal right now. Oh ... I don't know. GEORGE??? Last fiddled with by cheesehead on 20051122 at 01:05 
20051122, 02:05  #4  
Jun 2005
2×191 Posts 
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...oh, and just for you... 

20051122, 03:23  #5 
P90 years forever!
Aug 2002
Yeehaw, FL
2^{2}·3·641 Posts 
The way prime95 does stage 1 makes it possible to increase B1 midway through stage 1, but impossible to decrease B1 midway through stage 1.
Stage 2 / B2 is even more complicated! 
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