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Alternate cryptocurrencies / Altcoin Discussion / Re: [XPM] Primecoin Builtin Miner Sieve Performance Issue

on: July 13, 2013, 02:38:44 PM

Someone has to determine the miner situation. Which one works best for intel and AMD, Sandy, Ivy, Haswell, FX etc. I'll help you. Consider we have currently ~1 block found every 5 seconds. Consider the whole network has probably over 4m pps total right now. It comes down to rolling a dice every 5 seconds. For example, with my insane 250pps, I have approximatively 0.006% chance to get a block every 5 seconds. Understand why you haven't found one, now ? assuming a 4M pps network and that probability is proportional to pps, for each thousand of pps you should get four blocks per day. How high should the difficulty be at 4M pps?



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Alternate cryptocurrencies / Altcoin Discussion / Re: [Bounty] Primecoin Standalone CPU Miner! Current: 2.5BTC

on: July 13, 2013, 05:26:36 AM

Pool share can be implemented as lower difficulty prime chains, similar to hashcash proofofwork I think.
I'm not sure this is the case, or at least it is not as simple. With hashcash proofofwork it is impossible to look for lower difficulty shares without also looking for higher difficulty shares. In Primecoin, on the other hand, as I understand it, one could look for chains of length 7 and find them with much greater frequency than they would find chains of length 7 while looking for chains of length 8 (i.e. pool miners would maximize their share submission by hurting the pool; the tragedy of the commons ensues). I assume that when the mining algorithm executes it first executes the Sieve of Eratosthenes to build a list of possible primes. If one finds that there is a list of 7 numbers that passed the sieve and form a chain then they could be checked to see if they form a valid share, even if the sieve eliminated the next value, proving that a block of difficulty 8 or higher is impossible from that start (I am assuming a share difficulty of 7 and a network difficulty of 8 or more). A miner optimized for finding valid blocks as fast as possible would save computational time by ignoring the chain of length 7 when the difficulty is 8 or higher, while a miner optimized for finding valid shares would check every chain of primes that passes the sieve that is at least (share length) long. This could be circumvented by requiring the numbers after the share's chain up to the integral network difficulty to all pass a sieve, but I believe that that would break the requirement that shares be fast to verify by the pool host. Additionally, it would set stringent requirements on how the numbers would have to be sieved which would limit improvements to be made in that area (which seems to be where most of the improvements are being made). You've made a really innovative coin, Sunny, and I trust you to come up with an innovative solution to this, but it isn't as simple as it may appear at first glance. My p2pclient will beat this problem. By making a sub blockchain with difficulty one less than the main chain's, payment is based on all the blocks you have submitted during the round. The P2P chain will end up producing many many more primes than the main chain does, maybe somebody will take it upon themselves to create a listening node and just store them, since I won't be making a site for the pool it won't be me, which also means I can make it a nofee pool.



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Alternate cryptocurrencies / Altcoin Discussion / Re: [Bounty] Primecoin Standalone CPU Miner! Current: 2.5BTC

on: July 11, 2013, 08:49:51 PM

There is no "better" in any other coin I think you just proved my point here. I didn't say there is no logic in much of you've said, on the contrary, your explanation why other coins fail is interesting. I only think you underestimate the inertia of Bitcoin fundamentals, it *may* fork in a few decades if SHA256 is undermined, and it may switch to some new hash function but everything else will stay the same. Also, you are underestimating the new fundamental advantage of Primecoin: it will be very hard to implement it in GPU to be faster than CPU, unlike other coins. The advantage to mine with only CPU, gives many people a chance to mine, taken away from them by specialized GPU mining monsters. If Bitcoin had to change the PoW, that would probably end up killing it. By the time a reason comes to change the PoW, the amount of money invested in double SHA256 silicon would be much greater than it is today, and changing it would alienate the current mining community due to how expensive it would be to actually mine.



