[XPM] [ANN] Primecoin Release - First Scientific Computing Cryptocurrency

[Trillium]

Hi, I'm having trouble syncing my wallet now...
I added the muuttuja node, and am still getting crashes and errors when the wallet is about to sync.

Did you have the built-in miner running at the same time? AFAIK, those crashes occur randomly when mining. Also, some of your database files may be corrupt now because of the crash.

29 miners running here and never seen that error? Maybe I'm lucky.

[ivanlabrie]

Hi, I'm having trouble syncing my wallet now...
I added the muuttuja node, and am still getting crashes and errors when the wallet is about to sync.

Did you have the built-in miner running at the same time? AFAIK, those crashes occur randomly when mining. Also, some of your database files may be corrupt now because of the crash.

I used to...I now have an unconfirmed transaction there, stuck it seems.



It's been like that since yesterday. I erased all the files except for the wallet.dat but still get the same thing. Should I re download the wallet? Use a different folder, or what?

Thanks.

[IlyaVak]

What is best miner for solo mining XPM? 

[ivanlabrie]

What is best miner for solo mining XPM? 

Easy, the High Performance HP11 (or whatever version's the latest at any given time).
Search for it here, it's made by mikaelh, one of the developers.

[liquiddrool]

What is best miner for solo mining XPM? 

hp11 search this forum for it

[coin@coin]

Is there an HP12 being worked on at the moment? Seems like so long ago HP11 came out...
But then I guess most people is pool mining on Ypool or Beeeeer.

[mikaelh]

Primecoin is looking for chains that are at least 9 primes long (so k >= 9). The current mining algorithm is producing numbers that are about 300-bits long which is about 90 digits. The origin is always a multiple of the block header hash which is 256 bits long. This hash is then multiplied by a few small prime numbers and a multiplier produced by our sieve algorithm. The miner can occasionally try using big multipliers which may result in a new record if the numbers are primes.

Ah interesting. Sorry I'm not very good in c++ neither can I just simply change the code, compile and then find out. So in the miner you just multiply the block header (which is different to the showed hash in the explorer which is very confusing) which different primes? So the CSieveOfEratosthenes tries just to find this multipliers?

Sorry, I don't want to disturb u all the time. Are there somewhere more informations to the code?

Multiplying the hash with small prime factors is simply a trick to increase the chances of finding a prime chain. Lets say we have a number N such that N = 2 * 3 * 5 * 7 * n, i.e. N is divisible by 2, 3, 5 and 7. Now we know that none of these numbers are divisible by these prime factors: N - 1, N + 1, 2N - 1, 2N + 1, 4N - 1, 4N + 1, ... .

Filtering out the prime factor p_i from a random number M increases the chances M being prime by 1 / (1 - 1/p_i). So if you filter out all even numbers, you double the chances. If you filter all numbers divisible by 3, you increase the chances by 50%. And if you filter out both, the chances are tripled.

CSieveOfEratosthenes is also increasing the chances of finding prime chains by filtering out all numbers divisible by slightly larger primes. The chances of finding a prime chain increase slightly with every prime factor that is filtered out. The details of this process are pretty complicated. I think the only place where the algorithm is described is the code itself.

[satriani]

i think now the most important thing to primecoin is go to chines exchange or do something to aware chines people about how many advantages has primecoin vs bitcoin.

also invent better miner for PrimeCoin could cause higher difficult and lower reward, which could impact on price. Higher market-cap = more attention = faster introduct Primecoin on online shops

[ivanlabrie]

mikaelh, I'm having trouble with the wallet...it stopped syncinc despite me trying the fixes you guys suggested.
Not sure what's up with that, I got stuck with a transaction with 0 of 6 confirmations.

[mikaelh]

mikaelh, I'm having trouble with the wallet...it stopped syncinc despite me trying the fixes you guys suggested.
Not sure what's up with that, I got stuck with a transaction with 0 of 6 confirmations.

Well, you can try looking at the debug.log file to see if there's a cause there. The file is in the %APPDATA%\Primecoin folder since you're on Windows. If all else fails, you can try deleting the database files in that folder. Make sure to preserve wallet.dat though.

[ivanlabrie]

mikaelh, I'm having trouble with the wallet...it stopped syncinc despite me trying the fixes you guys suggested.
Not sure what's up with that, I got stuck with a transaction with 0 of 6 confirmations.

Well, you can try looking at the debug.log file to see if there's a cause there. The file is in the %APPDATA%\Primecoin folder since you're on Windows. If all else fails, you can try deleting the database files in that folder. Make sure to preserve wallet.dat though.

Done that, didn't work...I don't get it. How can I tell if the time is incorrectly set? I have a few coins stuck there.

[mikaelh]

mikaelh, I'm having trouble with the wallet...it stopped syncinc despite me trying the fixes you guys suggested.
Not sure what's up with that, I got stuck with a transaction with 0 of 6 confirmations.

Well, you can try looking at the debug.log file to see if there's a cause there. The file is in the %APPDATA%\Primecoin folder since you're on Windows. If all else fails, you can try deleting the database files in that folder. Make sure to preserve wallet.dat though.

Done that, didn't work...I don't get it. How can I tell if the time is incorrectly set? I have a few coins stuck there.

Check the date (including year), the time and the timezone. Which block are you getting stuck on? You can compare that to the block count here:
http://primecoin.21stcenturymoneytalk.org/

[muto]

What is best miner for solo mining XPM? 

Easy, the High Performance HP11 (or whatever version's the latest at any given time).
Search for it here, it's made by mikaelh, one of the developers.

Are you sure? I solomine with  rdebourbon miner and get pretty good results.

[ivanlabrie]

Ok, rolled back to the primecoin client found at primecoin.org (not the high perf one) and erased all blocks and stuff but not my dat.
Got a new payment in, but the aforementioned stuck deposit is still stuck at 0 confirmations.
Here's the txid: 368f08fc87b8712432be07549201de515122345f26583ba4409bc42f6e78d618-000

Any clues?

[mikaelh]

Ok, rolled back to the primecoin client found at primecoin.org (not the high perf one) and erased all blocks and stuff but not my dat.
Got a new payment in, but the aforementioned stuck deposit is still stuck at 0 confirmations.
Here's the txid: 368f08fc87b8712432be07549201de515122345f26583ba4409bc42f6e78d618-000

Any clues?

Looks like that transaction never made it to the network. Unsent transactions are stored in the wallet.dat file. If you keep the wallet running, it should eventually resend that transaction. Did you check whether the date and time were correct?

If you want to get rid of the unconfirmed transaction, you can use -salvagewallet which will extract only the private keys from your wallet and ignores the transactions. As always, it's best to make a copy of your wallet.dat before doing this.

[donut]

I actually just did getrawtransaction to get the signed tx and then broadcasted via sendrawtransaction from another node.

[ivanlabrie]

Ok, rolled back to the primecoin client found at primecoin.org (not the high perf one) and erased all blocks and stuff but not my dat.
Got a new payment in, but the aforementioned stuck deposit is still stuck at 0 confirmations.
Here's the txid: 368f08fc87b8712432be07549201de515122345f26583ba4409bc42f6e78d618-000

Any clues?

Looks like that transaction never made it to the network. Unsent transactions are stored in the wallet.dat file. If you keep the wallet running, it should eventually resend that transaction. Did you check whether the date and time were correct?

If you want to get rid of the unconfirmed transaction, you can use -salvagewallet which will extract only the private keys from your wallet and ignores the transactions. As always, it's best to make a copy of your wallet.dat before doing this.

I didn't send any $$ from my wallet...I think it's an inbound transaction, a pool payment (probably).

[Supercomputing]

Sunny King
Primecoin Mining Research
http://www.peercointalk.org/index.php?topic=813

I am not sure if the Primecoin forum is very active, therefore I am posting my response to the posting above here also.

@Sunny
I am new to Primecoin but by no means new to Number Theory. I briefly looked at the source code of the latest version of mikaelh2's enhancements and I did not see much room for improvement. Using GMP for the modular exponentiation seems to be the biggest improvement. You can use the mod 60 wheel (sieve of Atkin) for the sieving step but I do not see that improving the overall run-time by any significant amount. The bottle neck is with the modular exponentiation of large numbers and Montgomery multiplication can be used to reduce multiplication time. But off course, Montgomery multiplication has its drawbacks, you are working with many different residue classes.

So now, there are two possible directions for the research of finding longer chains faster. The first direction is to continue making incremental improvements to the sieving and modular exponentiation arithmetic (brute force). And the second direction (which I prefer) is to analyze all of the data collected so far and come up with better arithmetic for finding longer chains. I assume that this was the reason that made Primecoin unique, otherwise it is no different from Bitcoin mining.

Unfortunately, carrying out the research to analyze collected data will require funding. I have been running "Primecoin version v0.1.2.0xpm-hp11-unk-beta" for 4 days now on a 32/64 core/thread server and I have only mined a block (primemeter  43807850 prime/h 663367364 test/h  180 7-chains/h 8.075400 chain/d). I just cannot see how anyone, other that people who have access to botnets, can be profitable at mining Primecoin.

Also, I am currently working on a GPU (Nvidia CUDA/PTX) off-load engine for the modular exponentiation (Montgomery) for the Primecoin miner. A GTX 580 should have the same throughput as all 32 cores/64 threads combined when performing Montgomery modular exponentiation. The sieve (of Atkin) will remain on the CPU to maximize performance.

@All
You can donate to the address below if you will like to see this research progress.
ALAxNNtF2hBPUpXFdN8Xexp1HbKwh4JeEK (Primecoin)
1MCqoWLA3eyqovRXKCydoDSfNN8C28y3k2 (Bitcoin)

[satriani]

Supercomputing: can you tell us if GPU could mine 10x faster then CPU in the nearest future ? Is it possible? Or other FGPA/ASIC stuff could be used to mine PrimeCoin?

[Supercomputing]

Supercomputing: can you tell us if GPU could mine 10x faster then CPU in the nearest future ? Is it possible? Or other FGPA/ASIC stuff could be used to mine PrimeCoin?

Montgomery multiplication - Coarsely integrated operand scanning (CIOS) @ 256-bit
An Nvidia GTX 580 (reference design ) is about 7x faster than an AMD Phenom II X6 1100T using all six cores

Montgomery multiplication for GPU - must use hand optimized PTX (unrolled)
Montgomery multiplication for CPU - must use hand optimized x64 assembly (unrolled)

I would put the GPU at about 7x that of the CPU since modular multiplication is the bottle neck and not sieving.


FPGA's will only be useful for primorial searching, they are not cost effective for modular multiplication.