Bitcoin Forum

Alternate cryptocurrencies => Mining (Altcoins) => Topic started by: funkenstein on January 25, 2015, 09:56:50 PM



Title: Three months pure CPU woodcutting - a challenge for GPU / FPGA / ASIC devs
Post by: funkenstein on January 25, 2015, 09:56:50 PM
Greetings miners -

  We have now been chopping LOG for three months using only CPUs.  The algorithm is pure double Skein.  Is there any other coin that can claim pure CPU mining at this stage?   

 

  Thanks --   

funkenstein the dwarf


Title: Re: Three months pure CPU woodcutting - a challenge for GPU / FPGA / ASIC devs
Post by: funkenstein on January 26, 2015, 12:55:21 AM
Greetings miners -

  We have now been chopping LOG for three months using only CPUs.  The algorithm is pure double Skein.  Is there any other coin that can claim pure CPU mining at this stage?    

  

  Thanks --  

funkenstein the dwarf

Just because the coin isn't worth anything doesn't mean it's impervious to better mining techniques - just that no one cares.

True indeed.  However it appears there are people who care about hash functions and cryptography.  Hence the experimental cryptocurrency.  My goal in this thread is to learn something about the Skein hash function and it's applicability to proof of work consensus.  I am hopeful woodcoin will help encourage folks to study this problem. 


Title: Re: Three months pure CPU woodcutting - a challenge for GPU / FPGA / ASIC devs
Post by: djm34 on January 26, 2015, 02:31:28 AM
skein isn't cpu only  ;D not sure where you saw that. I am pretty sure there is already a sgminer version (and a ccminer I haven't released  ;D)

edit: double skein... well (nope I haven't coded that yet. I have only coded skein256,skein512,skein1024)

edit 2: if you want your coin to stay cpu only, don't come brag here  ;D


Title: Re: Three months pure CPU woodcutting - a challenge for GPU / FPGA / ASIC devs
Post by: funkenstein on January 26, 2015, 03:45:00 AM
Greetings miners -

  We have now been chopping LOG for three months using only CPUs.  The algorithm is pure double Skein.  Is there any other coin that can claim pure CPU mining at this stage?    

  

  Thanks --  

funkenstein the dwarf

Just because the coin isn't worth anything doesn't mean it's impervious to better mining techniques - just that no one cares.

True indeed.  However it appears there are people who care about hash functions and cryptography.  Hence the experimental cryptocurrency.  My goal in this thread is to learn something about the Skein hash function and it's applicability to proof of work consensus.  I am hopeful woodcoin will help encourage folks to study this problem. 

What version does it use? I know Skein forwards and backwards.

Thanks for your reply!

It uses skein512,  in particular a C implementation written by Thomas Pornin.  I believe this is the same implementation used by many other coins which use multiple hash functions but in this case the proof of work function is skein512(skein512(block header)).

Er, just curious..  do you really know Skein backwards? ;) 

 


Title: Re: Three months pure CPU woodcutting - a challenge for GPU / FPGA / ASIC devs
Post by: funkenstein on January 26, 2015, 04:34:53 AM

[snip]

Haha, it's an expression. That SPH implementation is pretty shitty. Skein-512 is cake to implement, though.

Tell me more :)  Do you refer to the efficiency in terms of hashes per cycle?  Is there a better reference implementation you would recommend looking at?   


Title: Re: Three months pure CPU woodcutting - a challenge for GPU / FPGA / ASIC devs
Post by: funkenstein on January 28, 2015, 06:23:32 PM

[snip]

Haha, it's an expression. That SPH implementation is pretty shitty. Skein-512 is cake to implement, though.

Tell me more :)  Do you refer to the efficiency in terms of hashes per cycle?  Is there a better reference implementation you would recommend looking at?   

It's ugly as sin. It performs okay, but hell to understand. It's also terrible on GPU - but that's not a failing of the code, more of the idiot who copy+pasted it.

lol, and now it is everywhere.  Probably the most used implementation as it exists now on thousands of boxes running various multi-hash coins.