20110217, 19:56  #1 
Bemusing Prompter
"Danny"
Dec 2002
California
2,341 Posts 
LL tests more creditefficient than P1?
I've assigned three desktops (all with i5650 processors) to do P1 factoring exclusively. From what I've noticed, each P1 assignments takes about 1.8 days to complete gives exactly 4.6787 GHzdays of credit, provided that no factor is found in stage 1.
4.6787 / 1.8 = 2.6 GHzdays / (core * day) However, another i5650 desktop is LLtesting a 52M exponent. Each iteration takes 0.058 seconds; at this rate, it would take about 35 days for the assignment to finish. An exponent of this size gives about 110.5 GHzdays of credit, or about 3.15 GHzdays / (core * day). Is there an explanation for this discrepancy? Are LL tests more computationally intensive? Or does the code for calculating P1 credit need to be adjusted? 
20110218, 01:30  #2 
6809 > 6502
"""""""""""""""""""
Aug 2003
101×103 Posts
23D8_{16} Posts 
You may want to see this thread:
http://www.mersenneforum.org/showthread.php?t=11411 
20110220, 12:24  #3 
Mar 2003
Melbourne
1003_{8} Posts 
How much memory did you allocate to P1? I find allocating 500MB+ gave quicker results, than say 200MB.
Sorry I don't have exact figures. But I have 4x cores doing P1 stage at the time, the 500MB core was sitting at 40% compelte, while the other was sitting at 25% ish. Note this figures are from memory. It's more qualative comparison than quantitive.  Craig 
20110220, 16:24  #4 
Bemusing Prompter
"Danny"
Dec 2002
California
2,341 Posts 
I'm using 384 MB per core.

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