49

A share is a hash smaller than the target for difficulty of 1* (see clarification at end). Every hash created has a 1 in ~4 billion (2^32) chance of being a valid share. In comparison if the difficulty of network is 2,000,000 then a share is 2 million times "easier" to find than a valid hash for the block, and on average it will take 2 million shares (8 ...


30

Stale shares are the shares that were sent after a block was already solved, that is to say, they were sent late and were no longer valid. To avoid stale shares, best to have a reasonably fast mining rig (so you won't take too long to calculate a share, probably not a problem for most machines), reliable internet connection (stable, not necessarily fast), ...


22

A stale share occurs when you find a share and submit it to the mining pool after the pool has already moved on to the next block. The percentage of stale shares should be very low if everything's working correct, around 2 out of 1,000 shares or so. Several factors affect the stale share rate. The three most important are long polling, pool load, and miner-...


12

The way you describe it it's not possible. The pool sends you the template of the block that you ought to be working on. Should you really find a block it is bound to the block template you received from the pool, i.e., the nonce that satisfies the proof-of-work difficulty is only valid because it is valid in combination with the template. Since the block ...


11

Bitcoin miners find a random number (called a "Nonce") that when inserted into the current block makes the hash be below the current target. They then send that current block around the network and everyone checks their work (the proof-of-work) by hashing the block and checking if the result is below the current target. In mining pools, miners do the same ...


11

What do the mining workers do differently then if they would be mining solo? A miner that is mining within a third-party pool doesn't need the entire block chain. In fact it doesn't need to be connected to any peers of the Bitcoin network. These miners work entirely outside of the network and could technically just need to communicate to the administrator ...


10

An accepted share represents work that your miner did towards a round in a mining pool. When the pool finds a block, it distributes the block reward (i.e. 25BTC) to the miners according to how many shares they have contributed during that round. The more shares you contributed, the more payback you get. It is simply a way to keep score, and to attribute ...


9

The above answers are good but one thing I would add is that hashing rate affect stale share %. Why? Because with a faster miner a smaller % of shares are even "at risk" of being stale. Pools only pay for completed shares. A block is found on average every 10 minutes so in that 10 minute window the last share is the one at risk of being stale. Now the ...


8

To understand this we should first explain that a block with a high difficulty, let's say D, is also a share of low difficulty d < D, therefore if we find such a block for difficulty D we automatically have a block of difficulty d. This also means that if I as a miner am looking for a share with difficulty d I might by chance find a block of difficulty D (...


6

The hashes generated by your miner is only usable for a unique set of transactions that your pool decided to include. In addition each pool orders transactions differently and that too will affect the resulting hash. Unless the pools cooperate and synchronize all the details of a given block (nonce, merkle tree, etc) then any hash that is generated is ...


6

If the global network difficulty is D and the difficulty of shares in the pool is d, then the probability that a share will lead to a valid block is d/D. The reward in this case is B, so the average reward per share is B*(d/D). If the operator's average fee is f (so for example f=0.01 means 1% fee), the average reward miners get per share submitted is (1-f) *...


6

The higher difficulty means you will be reporting results less frequently to the pool. This reduces network load on both your system and the pool. It also reduces the restart delay for your mining hardware as it prepares for the next work unit. Most pools base the rewards on the number of difficulty 2 shares accepted. So they increase the reward based on ...


6

My guess is that you did not launch cgminer with the --scrypt option. This is required to mine Litecoin, Dogecoin or any other scrypt coin. When mining scrypt coins that card should deliver ~100 Kh/s in your screen shot it shows Mh/s which would indicate that you are using SHA256 which is for Bitcoin.


6

Contrary to popular belief, mining is not something where there is progress. Each hash has the same probability of being a valid block hash. You could get lucky and find a valid hash with your next hash, or you could not. There is no progress that is made. When you mine on a lower difficulty, the target that your hash must be under is much higher than that ...


5

Since pools only receive successfully calculated shares they must approximate your actual hashrate based on the number of shares submitted. Assuming we're talking about difficulty 1 shares, you should be able to approximate hashrate via H = S * 2^32 / T where H = hashrate, S = shares submitted and T = time in seconds. Your estimate will be more accurate for ...


5

The approximate ratio which is usually used in calculations is 2^32 hashes per share. If you want the exact ratio, it's 2^48/(2^16-1).


5

You should count each share as valuable as the difficulty of the pre-determined target for that miner. If you count the actual value of the hash it found itself, either the math won't work, or you'll introduce massive variance instead of reducing it (which a pool is intended to do). When you choose a particular share difficulty D, you are restricting the ...


5

In order to find a Block, one needs to perform A LOT of tries - about 2^32 * the current difficulty. That number is so huge that solo miners rarely would be able to solve a block. A share on the other hand is a block of difficulty 1, which is at the moment a few million times easier to find. Finding a share does not help in finding a block in any way - each ...


5

Blocks which only satisfy the requirement for a lower difficulty than the real network difficulty are called "shares". They are found naturally in the process of looking for valid blocks, and there is no way to find shares without doing the work needed to find blocks. Thus, shares prove that work has been done by the miner. Pools use these shares to ...


4

It should pay 100USD for every 713 shares (diff as I type). That refers to shares of a certain difficulty: diff 1 Litecoin shares or diff 65,536 shares according to some mining clients (notably CGMiner). Each found share has its difficulty. If the share's difficulty is equal to or higher than the worker's difficulty, it gets submitted by the worker and ...


4

From the wiki: "The average time to find a block can be approximated by calculating: time = difficulty * 2**32 / hashrate" This applies also to shares, setting 1 as the difficulty. At 1 MH/s, you can expect to find a share every 2^32 / 1000000 = ~4295s. Inversely, you will find (1000000/2^32) = ~0.000233 shares per second per MH/s.


4

The mining pool coordinates the workers. Think of it like a lottery. If you and your friends all buy tickets in the lottery the group has a better chance of winning. To be fair in the lottery example everyone should be rewarded proportional to the amount of money spent on tickets. So if there are 20 tickets for the pool one person purchased 10 and two people ...


4

The address the block reward goes to is in the data that is being hashed. That address is the pool's. If a miner finds a hash that meets the block difficulty, changing the address to the miner's own will cause a different hash, and you don't have control over the distribution of the bits in that second hash. So you don't get a block if you change the address....


3

Many things can affect your stale/reject rate. An overclocked or faulty GPU could be making miscalculations. The pool's long polling might not be working properly. Even network instability could cause rejects due to duplicate shares (the share was received by the server, but your miner got an error so it tries again). The way pool size would affect rejects ...


3

An invalid share might be a share you submitted with an error in calculations, or possibly a stale share, depending on the pool implementation. A possible reason for a rejection of a share might be that the pool doesn't use difficulty 1 as the target, while some miners might try submitting those shares There is also a possibility that your miner makes some ...


3

There's no reason pool size should affect the number of invalid shares. If you're seeing different amounts of invalid shares on different GPUs, the most likely explanation is that the GPU is too hot, improperly overclocked, or failing.


3

hashesPerSecond = math.pow(2, 32) * proofsOfWork / secondsElapsed where proofsOfWork is the number of difficulty 1 proofs of work (aka shares) that the user or pool has found during secondsElapsed seconds. If you use variable difficulty, then you can count a proof of work from someone mining at difficulty X the same as X proofs of work at difficulty 1. ...


3

Due to the very low probability of successful generation, this makes it unpredictable which worker computer in the network will be able to generate the next block. http://en.bitcoin.it/wiki/Proof_of_work This is what makes proof-of-work based cryptocurrencies like Bitcoin different from any other form of electronic money. With access to mining being ...


3

Your shares are towards a block, once a block is completed you start on a new block and go back to 0 shares. Depending on your pool, you get paid per block or per share. Don't worry, if you look on your pools website you should be able to find what you made off of the block and how many shares you contributed. Restarting GUIMiner will not remove your shares,...


3

There really isn't one when you are pool mining. Most pools these days use VarDiff to achieve the same number of shares per minute by changing your workers difficulty. Now, on a low end mining rig (lets say 20 kh/s) the number of shares accepted may vary greatly as you may have some great luck with your share or it may be bad luck. So as long as you have a "...


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