Strategic Double Clicking

[Mark Rose]

Originally Posted by bgbeuning

I would like to know if any of my machines are producing bad results.
Is there a way to find out?

Go to http://www.mersenne.org/cpus/ and look at the reliability rating. A CPU with no verified results will get a reliability rating of 0.98, as that's the average. If you want to test your CPUs, configure your machines to run some double checks.

[GP2]

Originally Posted by bgbeuning

I would like to know if any of my machines are producing bad results.
Is there a way to find out?

Your only verified bad result in the database is M39761383. The machine was "opt24".

You can log into mersenne.org and look at http://www.mersenne.org/results/ to see your own results. Any mismatches are prominently flagged; if so, obviously it could be your result that's bad, or the other result, or both. To see them all you might need to increase the default of "100" in the "Show up to _____ results" field.

[kladner]

Originally Posted by bgbeuning

I would like to know if any of my machines are producing bad results.
Is there a way to find out?

Run double checks. Add up the preponderance of results. Some of this may require triple checks to resolve. If you get verified results (matching someone else's results), and no proven bad results (two others match, but not you), you are in pretty good shape.

If some machine not only mismatches, but is proven wrong, it is time to start testing and adjusting.
[Cross posted with GP2. That information is informed, while my response is entirely general.]

[dragonbud20]

I'll do these it's all the triples below 44M from that list

Originally Posted by Madpoo

exponent	worktodo
42905069	DoubleCheck=42905069,72,1
42917263	DoubleCheck=42917263,72,1
42929317	DoubleCheck=42929317,72,1
42958469	DoubleCheck=42958469,72,1
42966571	DoubleCheck=42966571,72,1
42985493	DoubleCheck=42985493,72,1
42994879	DoubleCheck=42994879,72,1
43000721	DoubleCheck=43000721,72,1
43021193	DoubleCheck=43021193,72,1
43029247	DoubleCheck=43029247,72,1
43029307	DoubleCheck=43029307,72,1
43030081	DoubleCheck=43030081,72,1
43030921	DoubleCheck=43030921,72,1
43045459	DoubleCheck=43045459,72,1
43065563	DoubleCheck=43065563,72,1
43110401	DoubleCheck=43110401,72,1
43273631	DoubleCheck=43273631,72,1
43287953	DoubleCheck=43287953,72,1
43292497	DoubleCheck=43292497,72,1
43297061	DoubleCheck=43297061,72,1
43312639	DoubleCheck=43312639,72,1
43384801	DoubleCheck=43384801,72,1
43414927	DoubleCheck=43414927,72,1
43423663	DoubleCheck=43423663,72,1
43727513	DoubleCheck=43727513,72,1
43775617	DoubleCheck=43775617,72,1
43803289	DoubleCheck=43803289,72,1
43832177	DoubleCheck=43832177,72,1
43906003	DoubleCheck=43906003,72,1
43963379	DoubleCheck=43963379,72,1

[bgbeuning]

Originally Posted by Mark Rose

Go to http://www.mersenne.org/cpus/ and look at the reliability rating. A CPU with no verified results will get a reliability rating of 0.98, as that's the average.

Do not see reliability rating.

[sdbardwick]

Originally Posted by bgbeuning

Do not see reliability rating.

Click on a computer name for computer properties.

[Madpoo]

Originally Posted by GP2

Your only verified bad result in the database is M39761383. The machine was "opt24".

You can log into mersenne.org and look at http://www.mersenne.org/results/ to see your own results. Any mismatches are prominently flagged; if so, obviously it could be your result that's bad, or the other result, or both. To see them all you might need to increase the default of "100" in the "Show up to _____ results" field.

That's the only one I saw also (and was delighted to see that my result was the tie-breaker in that 3-way race, but then I tried to snag all the quad checks that I could).

I see a total of 32 different systems from him that had returned an LL result at some point or another.

That particular system with the bad result has 160 good (one is "assumed" good based on the other system being sketchier), and 24 still unknown.

[bgbeuning]

Originally Posted by GP2

Your only verified bad result in the database is M39761383. The machine was "opt24".

I checked the results.txt for that exponent but there were no special case messages.
Some exponents get this message

Trying 1000 iterations for exponent 37059551 using 1920K FFT.
If average roundoff error is above 0.24245, then a larger FFT will be used.
Final average roundoff error is 0.22443, using 1920K FFT for exponent 37059551.

Thanks everyone for the tips on checking machine stability.

[GP2]

Originally Posted by bgbeuning

I checked the results.txt for that exponent but there were no special case messages.

That's because it was not known at the time that the result was wrong.

If you look at the report for M39761383, you can see that you checked in your result on 2016-01-21, and it was not until Madpoo checked in his quadruple-check result on 2016-02-22 that it was known that your result was wrong.

However, if you log in to mersenne.org and look at http://www.mersenne.org/results/ (not the results.txt file on your disk), then it should flag any mismatches or bad results. Again, to see all your old results you might need to increase the default of "100" in the "Show up to _____ results" field.

[Mark Rose]

Everything below 50M from the triple check list has been assigned.

[endless mike]

It looks like these all finished within the last few days while I was at work. I matched you on all of them.

Originally Posted by endless mike

I grabbed the rest of the list. You (among others) have helped whittle down my list of exponents needing a triple check, so I can help with some of yours.

Originally Posted by Mark Rose

I have 25 exponents that need a triple check, if anyone is interested:

DoubleCheck=61756243,74,1
DoubleCheck=61841803,74,1
DoubleCheck=61843973,74,1
DoubleCheck=61844329,74,1
DoubleCheck=61846193,74,1
DoubleCheck=61995611,74,1
DoubleCheck=62012707,74,1
DoubleCheck=62796527,74,1
DoubleCheck=63773497,74,1
DoubleCheck=64071221,74,1
DoubleCheck=67876027,74,1
DoubleCheck=68804809,74,1
DoubleCheck=70869973,75,1
DoubleCheck=71069681,75,1
DoubleCheck=71642387,75,1
DoubleCheck=76417333,75,1
DoubleCheck=77133689,75,1