Bitcoin Forum

Bitcoin => Mining => Topic started by: bulanula on October 05, 2011, 06:48:20 PM



Title: Solo mining questions and clarifications
Post by: bulanula on October 05, 2011, 06:48:20 PM
Just a question about solo mining. How does the network "record" that you are mining when doing it solo.

For example, if on average it takes 12 hours to make a block do I have to leave the computer on 12 hours without interruption and then get my block OR can I leave for 6 hours then turn off computer for 1 minute then run for 6 hours again and at end I get my block as network "remembers" I have been doing the proof of work even before computer was turned off then started again etc. !?

With a pool, they can see the shares submitted etc. but how does that work while soloing !? Who / what keeps record how many "shares" each solo miner did or how many hashes he has done etc. to get the block !?

Also, say there are two miners that have same power and soloing. Is there like a queue which miner gets the blocks etc. !? Or for example the miner with the most solo power gets this block then the next less powerful miner gets this block etc. !?

Thanks !


Title: Re: Solo mining questions and clarifications
Post by: DeathAndTaxes on October 05, 2011, 07:51:55 PM
The network doesn't record anything (for solo or pool).

Every hash has an equal chance.  Like buying a lottery ticket.  It either wins or it loses.

At current difficulty you have a 1 in 7,255,634,282,020,860 chance of finding a "winning" hash.  Period.

Every new hash is another chance.  If you have a 100MH/s miner then you get 100 million chances to "win" every second.

The losing hashes/tickets are completely worthless.  

The only reason pools records shares is to "fairly" (some more fair than others) have a mechanism to divide the reward on a winning hash/ticket.  All the shares are worthless except the one which solves a block.  When 1 miner finds a solution to the block the pool needs to know how to split that reward and to do so they need to know how many attempts each miner contributed.    To keep miners honest the mining software returns to pools a losing (not small enough hash) hash but a hash which is somewhat rare.  The hashes returned to a pool occur roughly once every 4,294,967,296 hashes.    A pool calls that 1 share.  By recording how many shares each miner returns the pool has a method to fairly and honestly determine how many hashes each miner attempted.

Still the shares are utterly and completely worthless.  There is only 1 hash that is worth anything, it is the solution and it is worth the entire block reward (currently 50 BTC).

As far as two miners and one is stronger.  Each one has an equal chance PER HASH.  The stronger miner simply tries more hashes per second.  Kinda like if you and I play the lottery every week but you can only afford to play $1 and I play $10.  The ticket either wins or loses.  I simply get to buy more tickets.

Short version:
1) Only the winning hash is worth anything.  The "network" only records the winning hash.
2) You don't work towards a winning hash.  You either win or you lose.  If you lose then you try again (and again billions and billions of times).
3) If you mine 100 billion hashes and they all are losers then you are no "closer" to winning hash than on first hash.  Each hash has an equal chance of winning.
4) Shares in a pool are worthless.  They are simply a mechanism to keep miner's honest.  The only share worth anything in a pool is the one that solves a block.

Think of bitcoin like a lottery where each hash you generate is like buying a ticket and the "winner" solves the block and gets the reward.  It is the easiest way to understand how mining works.

So can you answer your own question now?
Do you need to leave miner on 12 (or x) hours?  Does it matter if you turn it off for a minute?  If you mine for 30 days and have found no blocks and then lose power have you lost anything?


Title: Re: Solo mining questions and clarifications
Post by: bulanula on October 05, 2011, 08:07:14 PM
The network doesn't record anything (for solo or pool).

Each hash is an equal chance.  Like buying a lottery ticket.


At current difficulty every hash as exactly the same chance of being the winner.

You have a 1 in 7,255,634,282,020,860 chance of finding a "winning" hash.  Period.
Every new hash is another chance.  If you have a 100MH/s miner then you get 100 million chances to "win" every second.


The losing tickets are worthless.  Now for pools to keep track of how many hashes miners are trying (to split reward when a block is found) the pool will have you return losing but still difficult to find tickets/hashes.  On average you have a hash good enough for the pool every 4,294,967,296 hashes.  So you turn those in an each one tells the pool that you have mined roughly 4,294,967,296 hashes.  It is simply a mechanism to keep people honest.  Pools call those 1 share.  1 share ~= 4,294,967,296 hashes. 

Otherwise I could write a miner that told a pool "Yup I just mine 11 quadrillion hashes. they were all bad. please pay me".

Three key things to remember:
1) Only the winning hash is worth anything
2) You don't work towards a winning hash.  You either win or you lose.  Then you try again.  If you mine 100 billion hashes and they all are losers then you are no "closer" to winning hash than on first hash.
3) Shares in a pool are worthless.  They are simply a mechanism to keep miner's honest.  The only share worth anything in a pool is the one that solves a block.

The best way to understand it is the lottery analogy.  Every hash is a new ticket.  It either wins or it doesn't.  You could (very unlikely) win 2x back to back.  You could also mine for the rest of your life and never win = find a hash which solves a block.

If you don't have 20GH/s then honestly you shouldn't be solo mining.



Why not make this actually contribute to society rather than wasting energy to get some dumb number etc. !? It is not even finding new prime numbers etc. LOL

The POW should be actually something feasible and something of value.


Title: Re: Solo mining questions and clarifications
Post by: DeathAndTaxes on October 05, 2011, 08:11:03 PM
Why not make this actually contribute to society rather than wasting energy to get some dumb number etc. !? It is not even finding new prime numbers etc. LOL

The POW should be actually something feasible and something of value.

That is a difficult problem to come up with a protocol that "does useful work" AND meets bitcoins other requirements:
a) that blocks be awarded equally and randomly
b) that blocks be generated at an predictable rate
c) that nobody can circumvent the network without 51% hashing power (network strength)
d) has no central authority

adding e) create useful "work" is simply not possible (yet).

If you can figure out a mechanism to tie useful work to block chain network WITHOUT A CENTRAL AUTHORITY I will support your "new & improved" bitcoin.
It is a very difficult problem.

Also I wouldn't say it is useless.  I have an encrypted file system on my computer for privacy.  Everytime I read or write a file it must be decrypted or encrypted.  It isn't doing extra "useful work".  Is my whole hard drive encryption "useless"?  I would say no.  The purpose is to protect my files just like the purpose of hashing is to protect the bitcoin network, and validate transactions.


Title: Re: Solo mining questions and clarifications
Post by: jjiimm_64 on October 06, 2011, 01:56:31 AM
The POW should be actually something feasible and something of value.

It does give you something of value, its called bitcoins, currently worth about 5 bucks each.


Title: Re: Solo mining questions and clarifications
Post by: bulanula on October 06, 2011, 02:02:47 PM
The POW should be actually something feasible and something of value.

It does give you something of value, its called bitcoins, currently worth about 5 bucks each.

Well it keeps falling to 4.5 now :(


Title: Re: Solo mining questions and clarifications
Post by: jjiimm_64 on October 06, 2011, 03:49:43 PM
The POW should be actually something feasible and something of value.

It does give you something of value, its called bitcoins, currently worth about 5 bucks each.

Well it keeps falling to 4.5 now :(

I did say currently 5 bucks each...  they were up to 30 at one point..  point is, it is tangible and valuable


Title: Re: Solo mining questions and clarifications
Post by: Gabi on October 06, 2011, 03:58:30 PM

 
Why not make this actually contribute to society rather than wasting energy to get some dumb number etc. !? It is not even finding new prime numbers etc. LOL

The POW should be actually something feasible and something of value.

Sure.

How?

What? You have no idea?

Eh, that's the problem.