20070322, 22:00  #1 
Account Deleted
"Tim Sorbera"
Aug 2006
San Antonio, TX USA
10B7_{16} Posts 
Exponent Size Gap
I've checked the 10 million digit number only box since I started GIMPS and here's the exponents I've received:
M33983237 M34354007 (~370 thousand gap) M34657633 (~300 thousand gap) M35041399 (~380 thousand gap) M35431117 (just under 400 thousand gap) M38125771 (~2.7 million gap) The 35431117 one didn't take any longer than the others, but the gap difference is over 2 million. Is this because now even people that don't have the 10 million only box checked are getting 10 million digit exponents, so the amount that get done between the ones I do is a lot more? I know this is probably the reason...but I'm just wondering why the gap is so huge. 
20070323, 09:23  #2  
Dec 2002
2^{5}×3^{3} Posts 
Quote:
The reason you stated is indeed a major part of the answer to the question. Also, as exponents get reassigned after being abandoned, you can sometimes get an exponent that is smaller than the previous one you obtained. So, there is a lot of 'noise' in the assignments. 

20070323, 09:37  #3 
"Lucan"
Dec 2006
England
2·3·13·83 Posts 
About 6 months ago the "leading edge" of first time assignments
passed the 10,000,000 digit point and jumped to exponents~35,500,000 or so. So since then, it has moved faster in the 10,000,000+ digit range. 
20070323, 12:25  #4 
Account Deleted
"Tim Sorbera"
Aug 2006
San Antonio, TX USA
1000010110111_{2} Posts 
It was at ~35,500,000? That explains it. For almost the entire time between those two, anybody getting an assignment on firsttime or 10million checked out a number between those two.

20070323, 15:33  #5 
"Lucan"
Dec 2006
England
2×3×13×83 Posts 
How long do you take to check an exponent?

20070323, 16:47  #6 
1976 Toyota Corona years forever!
"Wayne"
Nov 2006
Saskatchewan, Canada
5^{2}×211 Posts 
It depends ... but I think the main factors are:
 Processor speed  Allocated memory  % of day you run Prime95 My 3.4Ghz takes about 28 days at the 35M range My 2.4Ghz takes about 35 days at the 35M range My now retired 400Mhz took 16 months at the 33M range They both run nearly continuous. 
20070323, 17:30  #7  
Account Deleted
"Tim Sorbera"
Aug 2006
San Antonio, TX USA
11×389 Posts 
Quote:
I started the one I'm currently doing on August 14, 2006, didn't do TF, then finished the P1 on August 24, 2006, and now it's going to finish the LL test today, March 23, 2007. That's a day under 7 months for the LL. The last one took two days over 7 months for the LL, so I'm pretty consistently 7 months for LL in the 35M range. That makes it equivalent to about 9.5 hours each day. So, davieddy, the short answer is seven months. 

20070323, 18:34  #8 
"Lucan"
Dec 2006
England
2·3·13·83 Posts 
THX when I said how long does it take "you" I was talking
to Minigeek, not the world in general. Personally, I am doublechecking 17,059,159 and am 93% through. Long shot to find a prime tho Taken ~ 6months on a PII. Last fiddled with by davieddy on 20070323 at 18:37 
20070325, 07:29  #9 
Dec 2002
2^{5}·3^{3} Posts 
All the exponents mentioned in the first post are exponents above the 10,000,000 digits range. But only part of the active GIMPS participants reserved exponents above the 10M digits range. (which is slightly above exponent 33,200,000) Now that we are out of first time LL assignments in the below 1)0M range all active participants reserve in the higher range most of the time. But even of more influence are the stress testing overclockers who reserve more than 50% of all assignments but never complete them. So the 'air bubble' that used to be in the below 10M range is now moving to the above 10M range. That explains most of the effect.

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