[Closed] [Bounty] Primecoin Standalone CPU Miner Current: 3.5BTC

[Jimmy2011]

I offer 1 XPM for the first CUDA Miner of Primecoin.

[diatonic]

I would be willing to kick in some LTC/BTC for a CUDA implementation. There are already projects that has proven that CUDA is apfar superior at Mersenne solving over general processing power and CUDA implementations of Mersenne solving has already been used to verify for example the 14th Mersenne solved.

Of course, being a natural born Cynic, as always there will be people who do this on their own (or already has) and will have an order of magnitude advantage in mining over the "general public" rather then sharing it with the forum.

Ill joining that one, and i offer 1BTC with the keyword CUDA in it. Got a 580GTX that need work.

Posted a hint on cudaminer author post. https://bitcointalk.org/index.php?topic=167229.940

I also have a GTX580 that would like some work other than scrypt in cudaminer and oclvanitygen.

[oroqen]

bump

[solracx]

Crossposting for exposure;

If anyone would like to give it a shot, there's an extremely optimized sieve of Eratosthenes implementation here:
https://primesieve.googlecode.com

From the software:

 The best sieving performance is achieved with a sieve size of your
  CPU's L1 data cache size (usually 32 or 64 KB) when sieving < 10^16
  and a sieve size of your CPU's L2 cache size above.

primesieve uses the segmented sieve of Eratosthenes with wheel factorization, this algorithm has a complexity of O (N log log N) operations and uses O (sqrt N) space.

Segmentation is currently the best known practical improvement to the sieve of Eratosthenes. Instead of sieving the interval [2, n] at once one subdivides the sieve interval into a number of equal sized segments that are then sieved consecutively. Segmentation drops the memory requirement of the sieve of Eratosthenes from O(N) to O(sqrt N). The segment size is usually chosen to fit into the CPU's fast L1 or L2 cache memory which significantly speeds up sieving. A segmented version of the sieve of Eratosthenes was first published by Singleton in 1969 [1], Bays and Hudson in [2] describe the algorithm in more detail.

From the source, the sieve size is small (1 * 10^6) by default if I'm interpreting it correctly.

I'm wondering if a massively parallel GPU implementation with higher memory bandwidth also benefiting from the reduced memory requirements will see much better performance.

Also,

primesieve generates the first 50,847,534 primes up to 10^9 in just 0.4 seconds on a single core of an Intel Core i7-920 2.66GHz, this is about 50 times faster than an ordinary C/C++ sieve of Eratosthenes implementation and about 10,000 times faster than trial-division. primesieve outperforms my older ecprime (fastest from 2002 to 2010) by about 30 percent and also substantially outperforms primegen the fastest sieve of Atkin implementation on the web. Here is a list of other fast sieve of Eratosthenes implementations.

If the current implementation is the standard C++ one (I haven't looked at it thoroughly but it seems to be), whoever can race to implement this first may benefit immensely.

For those interested, there's a CUDA implementation here too: http://www.mersenneforum.org/showthread.php?t=11900

The code works with native C++ integers and not CBigNum.  Not sure if CBigNumber is needed for Primecoin.  How big are the primes anyway?

[maka]

[
The code works with native C++ integers and not CBigNum.  Not sure if CBigNumber is needed for Primecoin.  How big are the primes anyway?
[/quote]

they are between 83digits and 268digits (decimal number) so far.

[Luke-Jr]

BFGMiner's "prime" branch seems to work, at 2000pps for me (on a system that primecoind was doing well under 100pps on, unoptimized).

It's not user friendly, and not intended to be easy to use, as it's still in development.
I'm not sure if I'm going to finish it, as I'm pretty sure Primecoin is a scamcoin - but maybe if others want to join in the development we can share the bounty?
Basically it mostly just needs cleanup at this point.

[Joe_Bauers]

What would designate it as a scamcoin? 

[achillez]

it's not bitcoin? 

[spirale]

as I'm pretty sure Primecoin is a scamcoin

Care to explain?

[Luke-Jr]

as I'm pretty sure Primecoin is a scamcoin

Care to explain?

There's no reason for people to adopt it.
If the prime POW proves to be demonstratably better than SHA256d, it could be adopted by Bitcoin with a hardfork.
Things like this (enhancement to a specific technical detail) should be done as testnet branches - as proposed changes to Bitcoin.

Without a hope of adoption, Bitcoin and forks function in a pyramid: when people get tired of it, the ones stuck with the coins in the end lose out.
Bitcoin is different because its innovation makes it possible to achieve a status quo where everyone wins (by having a usable decentralized currency).
Any new system would need to have a viable way to compete with Bitcoin (ie, something Bitcoin couldn't just adopt as an improvement).

Examples of altcoins that don't function as scams:

• Tonal Bitcoin: Compatible with BTC, uses the same blockchain. Whether it succeeds or fails, nobody loses value so long as Bitcoin as a whole doesn't fail.
• Namecoin: Not a currency, but a domain name system.
• PPCoin: Uses proof-of-stake instead of proof-of-work; arguably this is so fundamentally different that Bitcoin could not adopt it. Note that last I heard, PPCoin was being used as a scamcoin despite this, however, and there were some major problems with centralization/security tradeoffs.
• Freicoin: Features demurrage, which trades the "why spend it?" problem for a new "why acquire it?" problem. It would violate Bitcoin's social contract to make an economic change like this.

[itod]

as I'm pretty sure Primecoin is a scamcoin

Care to explain?

There's no reason for people to adopt it.
If the prime POW proves to be demonstratably better than SHA256d, it could be adopted by Bitcoin with a hardfork.
Things like this (enhancement to a specific technical detail) should be done as testnet branches - as proposed changes to Bitcoin.

Without a hope of adoption, Bitcoin and forks function in a pyramid: when people get tired of it, the ones stuck with the coins in the end lose out.
Bitcoin is different because its innovation makes it possible to achieve a status quo where everyone wins (by having a usable decentralized currency).
Any new system would need to have a viable way to compete with Bitcoin (ie, something Bitcoin couldn't just adopt as an improvement).

Examples of altcoins that don't function as scams:

• Tonal Bitcoin: Compatible with BTC, uses the same blockchain. Whether it succeeds or fails, nobody loses value so long as Bitcoin as a whole doesn't fail.
• Namecoin: Not a currency, but a domain name system.
• PPCoin: Uses proof-of-stake instead of proof-of-work; arguably this is so fundamentally different that Bitcoin could not adopt it. Note that last I heard, PPCoin was being used as a scamcoin despite this, however, and there were some major problems with centralization/security tradeoffs.
• Freicoin: Features demurrage, which trades the "why spend it?" problem for a new "why acquire it?" problem. It would violate Bitcoin's social contract to make an economic change like this.

The only reason Bitcoin would hardfork is the security of SHA256. There is no "better" in any other coin which would make Bitcoin switch to any other solution, so your criteria which is scamcoin and which is not is completely wrong.

[Luke-Jr]

There is no "better" in any other coin

I think you just proved my point here.

[megablue]

IMHO, bitcoin can adopt most of the features that based on bitcoin code, that is for sure.
However bitcoin is too big to make any decision to adapt new changes lightly without causing issues/mass panic.
any changes to bitcoin would affect tons of investors (eg, asic miners, manufacturers).

By the time bitcoin realized certain features (let say primecoin's POW ) is worthy to be implemented, the coin might already gaining too much momentum to be even stopped or slowed by bitcoin.

 

[mustyoshi]

There is no "better" in any other coin

I think you just proved my point here.

Primecoin is at least doing something that has use outside of itself.

[itod]

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.

[mustyoshi]

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.

[Luke-Jr]

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.

That's a bad thing.

For starters, mining exists to serve the users, not vice-versa.
Cryptocurrencies aimed at appealing to miners are fail by default.

Insofar as POW works in general... you cannot stop ASICs, period.
It simply is impossible.
With SHA256d, the availability of GPUs and FPGAs made it so the leap from CPUs to ASICs was bearable, and did not compromise Bitcoin's security.
Without the step of GPUs and FPGAs, this leap is almost certainly to be deadly to any cryptocurrency.
In the meantime, before ASICs make sense financially, you have a system that gives criminals (computer crackers) the ultimate authority.
So, to conclude, GPU-resistant is very bad for proof-of-work systems.

[itod]

Insofar as POW works in general... you cannot stop ASICs, period.
It simply is impossible.
With SHA256d, the availability of GPUs and FPGAs made it so the leap from CPUs to ASICs was bearable, and did not compromise Bitcoin's security.
Without the step of GPUs and FPGAs, this leap is almost certainly to be deadly to any cryptocurrency.
In the meantime, before ASICs make sense financially, you have a system that gives criminals (computer crackers) the ultimate authority.
So, to conclude, GPU-resistant is very bad for proof-of-work systems.

I disagree, it's not the point of stopping ASICs, they are the best thing happened to Bitcoin because they are ultimate protection from 51% attack. But there is no reason to develop ASICs for alter coins, regular people need access to cryptocoins for large adoption. People love lottery. You can't have global economy without very large adoption of currency, so Primecoin may actually be very, very good thing. There is a reason for such avalanche adoption comparing to other altcoins.

I didn't claim that XPM is GPU-resistant, to my limited knowledge it should be, but it may not be the fact. Certainly will be for some time, giving it a chance to be really broadly adopted.

[Ethera]

luke, your words:

arguably this is so fundamentally different that Bitcoin could not adopt it.

now think about differences in hashing sha, and calculating the primes.. are you realy realy trying to come out that ignorant idiot?

[achillez]

luke, your words:

arguably this is so fundamentally different that Bitcoin could not adopt it.

now think about differences in hashing sha, and calculating the primes.. are you realy realy trying to come out that ignorant idiot?

I don't follow - why the name calling?