20070527, 13:20  #12 
Jun 2003
11251_{8} Posts 
I can see how my post could be misunderstood that way. However the point I was trying to make was that you cannot analyze the "efficiency" of P1 without considering the LL cost. Supposing that the LL cost was more than 1200 hrs. In that case, Prime95 would've chosen Combo Z, despite the fact that the "efficiency ratio" indicated Combo X.

20070528, 04:37  #13 
"Richard B. Woods"
Aug 2002
Wisconsin USA
2^{2}·3·599 Posts 
Subconscious sez: P1 run time is proportional to not only the B1/B2 bounds (as in my example), but also FFT transform time (for mod 2^{p}1, same as used in LL), of course!
Sorry for my confusion, but I've never written this all down at once. I need to consult the source code, but I think this may be O() for typical autochosen B1/B2. So that "Expected Cost" column should be more like: 0.990 + 1.0 * O() 0.987 + 1.5 * O() 0.985 + 1.6 * O() ... which, I guess, is what I meant about the implied multiplication. Last fiddled with by cheesehead on 20070528 at 05:01 
20070528, 05:20  #14  
Sep 2002
2^{3}×37 Posts 
Quote:
actually thats what im looking for 1gig = 1.0% chance 1.5 gig =1.1% chance 2 gig = 1.5% chance some sort of graph like that 

20070528, 08:49  #15  
Jun 2003
17×281 Posts 
Quote:
Quote:
Let's cut to the chase. Do you understand why Prime95 cannot choose the optimal B1/B2 values /just/ by the ratio (chance of finding a factor)/(P1 cost)? 

20070528, 11:47  #16  
"Richard B. Woods"
Aug 2002
Wisconsin USA
2^{2}·3·599 Posts 
Quote:
exponent xxxxxxxx @ 1gig = 1.0% chance exponent xxxxxxxx @ 1.5 gig =1.1% chance exponent xxxxxxxx @ 2 gig = 1.5% chance exponent yyyyyyyy @ 1gig = 0.9% chance exponent yyyyyyyy @ 1.5 gig =1.0% chance exponent yyyyyyyy @ 2 gig = 1.4% chance exponent zzzzzzzz @ 1gig = 0.8% chance exponent zzzzzzzz @ 1.5 gig =0.9% chance exponent zzzzzzzz @ 2 gig = 1.3% chance One could plot a separate curve for each exponent on one xy graph with axes of Available Memory and chance of finding a factor. (Actually, there'd have to be a separate multiexponent graph for each CPU type.) 

20070528, 12:08  #17  
"Richard B. Woods"
Aug 2002
Wisconsin USA
2^{2}·3·599 Posts 
I'm temporarily having trouble concentrating in general, for medical reasons.
Quote:
It gave the incorrect impression that P1 run time was not dependent on exponent size or B1/B2 size. What I had meant in my original example was that for a particular, but unstated (which was confusing to the reader!!), exampleonly exponent and the given B1/B2, those were particular(unstated)exponentexampleonly run times for illustrative purposes. What I meant last post was that the P1 run times should have been 1.0 * O(), 1.5 * O(), 1.6 * O() instead of (10hrs, 15hrs, 16hrs). Or maybe it would've been clearer to write: 0.010 * O() 0.015 * O() 0.016 * O() since some (I, at least) may tend to think of O() as being close to 1 * in magnitude. Of course, what I really should have done was to present a rewritten example. Quote:
Last fiddled with by cheesehead on 20070528 at 12:46 

Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Memory Settings  Fred  Software  5  20160503 00:51 
Calculating optimal P1 memory  Uncwilly  Lounge  5  20130515 23:29 
Stage 2 Memory Settings  gamer30  Software  17  20120823 20:02 
Worker Windows  Optimal settings  Unregistered  Information & Answers  4  20100730 21:49 
What are optimal settings for Prime95 Torture Test  Discobadger  Information & Answers  3  20090403 11:48 