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Old 2012-12-28, 20:54   #1640
chalsall
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"Chris Halsall"
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Quote:
Originally Posted by kracker View Post
I'm experimenting with some GPU72 coordinated LMH. I need to apply a filter to not give the nominal amount of "GHz Saved" credit for such work.

Everything will be back to nominal in a few hours.
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Old 2012-12-28, 21:02   #1641
kracker
 
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Quote:
Originally Posted by chalsall View Post
I'm experimenting with some GPU72 coordinated LMH. I need to apply a filter to not give the nominal amount of "GHz Saved" credit for such work.

Everything will be back to nominal in a few hours.
Ahh, I see. That would be nice to have, btw
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Old 2012-12-29, 03:44   #1642
petrw1
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Quote:
Originally Posted by chalsall View Post
I need to apply a filter to not give the nominal amount of "GHz Saved" credit for such work.
Why not?....I realize as displayed that the numbers would be huge so that could just mean a seperate chart from regular TF. NO?
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Old 2012-12-29, 07:15   #1643
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How can you compare a factor found in lets say the 900M range with one in the LL range? Finding a factor in the 900M range is much easier and saves hundreds if not even thousands times the GHzdays if we finally get there in 100 years.
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Old 2012-12-29, 14:37   #1644
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Well, a 70 bit factor for a 900M is about equal (iirc) to a 66 bit factor for 56M. TF credit (should? does?) reflect this, but the simple truth is it does save so much time iff these exponents are ever LL tested. I picture it like this: a composite exponent also could have a "GHz saved" amount if anyone was stupid enough to run it without the known factor, but not stupid enough to run it with a known factor.
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Old 2012-12-29, 15:03   #1645
James Heinrich
 
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You need some kind of self-balancing metric, perhaps something along the lines of
Code:
worth = GHd_saved * (GHd_factor / GHd_LL)

// examples:
// 72-bit TF factor on 60M (TF to 273)
value = (133.292 + 133.292 + 15.94) * (11.956 / 133.292) = 89.7

// 72-bit TF factor on 900M (TF to 284)
value = (24825 + 24825 + 4352) * (0.5314 / 24825) = 1.2

// 83-bit TF factor on 900M (TF to 284)
value = (24825 + 24825 + 2176) * (1088 / 24825) = 2271

// 93-bit P-1 factor on 900M (TF to 284)
value = (24825 + 24825 + 0) * (684 / 24825) = 1368
This correctly shows that a 72-bit factor is worth a lot less on larger exponents than on smaller, despite "saving" a lot more LL effort. As can be seen above, it also works well with P-1 factors -- large factors can be found with relatively less effort than TF factors, but the above automatically scales it in what I think is an appropriate manner.
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Old 2012-12-31, 20:37   #1646
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Quote:
Originally Posted by chalsall View Post
I'm experimenting with some GPU72 coordinated LMH. I need to apply a filter to not give the nominal amount of "GHz Saved" credit for such work.

Everything will be back to nominal in a few hours.
Is this related in any way to the non-updating of the table of
LL trial factoring work (/reports/workers/lltf/)? The graphs
appear to be updated, but the table is outdated. And it
doesn't appear to be a cache problem at my end.

Gareth
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Old 2013-01-08, 23:01   #1647
James Heinrich
 
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mfaktc v0.20's recent release brings GPU-sieving into the game. And much increased performance (in the order of 30-50%). TF levels for GPU72 may need to be reconsidered?

http://mersenne.ca/cudalucas.php?model=13&granularity=2
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Old 2013-01-08, 23:23   #1648
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Quote:
Originally Posted by James Heinrich View Post
mfaktc v0.20's recent release brings GPU-sieving into the game. And much increased performance (in the order of 30-50%). TF levels for GPU72 may need to be reconsidered?

http://mersenne.ca/cudalucas.php?model=13&granularity=2
74 is the new 72!
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Old 2013-01-08, 23:41   #1649
Prime95
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Quote:
Originally Posted by James Heinrich View Post
TF levels for GPU72 may need to be reconsidered?

http://mersenne.ca/cudalucas.php?model=13&granularity=2
Question: Look at row 47M, the cyan color indicates we should TF to 2^73, but the 2LL column indicates the TF breakeven is 72.3 bits. Am I missing something?
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Old 2013-01-08, 23:41   #1650
James Heinrich
 
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Quote:
Originally Posted by swl551 View Post
74 is the new 72!
Starting at about 57M, I'd say that's true.

According to my chart:
46M-56M = 273
57M-72M = 274
73M-90?M = 275

Last fiddled with by James Heinrich on 2013-01-08 at 23:45 Reason: can't count
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