20081130, 14:46  #1 
Nov 2008
Rosenheim, Germany
11000_{2} Posts 
Double check LL test faster than first run test
Why is a double check LL test about twice as fast than a first run LL test?
As far as I understood LL testing the number of iterations has to be the same for both kinds of LL tests. Is it because a first run LL test does some intermediate error detecting, which a double check leaves out? What else could it be to make a double check faster then a first run check? 
20081130, 15:57  #2  
Jun 2003
13^{2}×29 Posts 
Quote:
However, at any given point in time, the exponents given out for first time testing will be much bigger than the ones handed out for doublecheck. Does that answer your question? 

20081201, 01:14  #3  
"Richard B. Woods"
Aug 2002
Wisconsin USA
2^{2}·3·641 Posts 
Quote:
If what you're comparing is the elapsed time taken by a DC now to the elapsed time taken for the first LL test back when it was first tested, consider that the average computer used by GIMPS participants has gotten faster over time. So the (perhaps) 2.66 GHz system that does the DC may do so in half the time needed by the (perhaps) 1200 MHz system that did the first test. Last fiddled with by cheesehead on 20081201 at 01:16 

20081203, 15:12  #4  
Sep 2002
Oeiras, Portugal
1,451 Posts 
Quote:


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