Topic: Proper PPLNS lastNshares calculation for script based coin pools - CLOSED (Read 5081 times)
May 30, 2013, 05:33:50 PM
Anyone looking for the solution, please go here : https://bitcointalksearch.org/topic/proper-pplns-lastnshares-calculation-for-script-based-coin-pools-solved-220341
May 30, 2013, 04:05:56 PM
No ideas ?
maybe if you give more than 30 minutes for someone to write a reply... May 30, 2013, 01:27:28 PM
No ideas ?
May 30, 2013, 12:58:41 PM
As most of you know the PPLNS calculation in mmcFE by default is based upon a fixed number. This isn't really the way PPLNS is supposed to work. It needs to be based upon the block difficulty at the time.
The normal calculation that I can find is difficulty * 2 = lastNshares, but this doesn't make sense for script based coins, even if you multiply the difficulty * 65536 as cgminer does.
Example, WDC's current difficulty is 1.62864385. 1.62864385 * 65536 = 106,168.32, which as I understand it is why CGMINER reports 107k as the block difficulty (it rounds). But this would yield a lastNshares value of 212,337 (rounded) shares. This doesn't make any sense as the average number of shares necessary to solve a block on my WDC pool is a little over 12,000 at the moment.
Since scrypt mining is about 1/1000 as efficient as SHA256 mining (kh/s instead of mh/s) I thought about dividing this figure by 1,000, but that also yields a number that doesn't make any sense, namely 212 shares (rounded).
Dividing the figure by 10 would yield 21,233 shares and that seems reasonable. Some rounds are more than that and some are less, but I just picked that out of thin air and would like some input on what a proper calculation would be.
Hopefully someone with a better understanding of the math involved can chime in and help me out here. I'd like to thank you guys in advance for your time. I searched the forums but did not find anything relevant.
The normal calculation that I can find is difficulty * 2 = lastNshares, but this doesn't make sense for script based coins, even if you multiply the difficulty * 65536 as cgminer does.
Example, WDC's current difficulty is 1.62864385. 1.62864385 * 65536 = 106,168.32, which as I understand it is why CGMINER reports 107k as the block difficulty (it rounds). But this would yield a lastNshares value of 212,337 (rounded) shares. This doesn't make any sense as the average number of shares necessary to solve a block on my WDC pool is a little over 12,000 at the moment.
Since scrypt mining is about 1/1000 as efficient as SHA256 mining (kh/s instead of mh/s) I thought about dividing this figure by 1,000, but that also yields a number that doesn't make any sense, namely 212 shares (rounded).
Dividing the figure by 10 would yield 21,233 shares and that seems reasonable. Some rounds are more than that and some are less, but I just picked that out of thin air and would like some input on what a proper calculation would be.
Hopefully someone with a better understanding of the math involved can chime in and help me out here. I'd like to thank you guys in advance for your time. I searched the forums but did not find anything relevant.
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