In the Bitcoin mining process, miners use computational power to solve complex mathematical puzzles to validate and confirm transactions on the Bitcoin network. When a miner successfully solves a puzzle, they are rewarded with a certain amount of newly minted Bitcoins (block subsidy), along with any transaction fees associated with the transactions they confirmed.
However, not all mining attempts are successful. Miners often work together in mining pools to increase their chances of successfully solving a block and receiving the reward. When a miner contributes their computational power to a pool, they receive work units to solve. These work units are divided into “shares.” But did you know there are accepted and rejected shares? In this article, we will delve into what these are and what a good ratio is between the two. Topics Covered:
What are Shares and How Do Shares Work?
Accepted Shares
Rejected Shares
Common Reasons for Rejected Shares
What is a Good Accepted/Rejected Ratio?
NiceHash is an open marketplace that connects sellers or miners of hashing power with buyers of hashing power. Buyers select the crypto-currency that they want to mine, a pool on which they want to mine, set the price that they are willing to pay for it, and place the order. This order is then forwarded to everyone who is connected to NiceHash with NiceHash Miner or other mining hardware (like ASICs). The computing power you provide will fulfil the buyer’s order and you get paid for this service.
What are Shares and How do Shares Work?
In the Bitcoin mining process, “shares” refer to units of work that miners contribute towards solving a cryptographic puzzle to validate and confirm transactions on the Bitcoin network. These shares are essentially partial solutions to the complex mathematical problems that miners are attempting to solve. Here’s how shares work in the Bitcoin mining process.
Mining Pools: Many miners join mining pools to combine their computational power and increase their chances of successfully solving a block and receiving a reward. Mining pools distribute work among their participants in the form of shares.
Work Units: When a miner joins a mining pool, they receive work units from the pool’s server. These work units represent portions of the overall cryptographic puzzle that needs to be solved to validate a block of transactions.
Solving Shares: Miners use their computational power to attempt to solve these work units. While each work unit may not be a complete solution to the entire puzzle, miners can find partial solutions or “shares” that demonstrate progress towards solving the overall puzzle.
Submitting Shares: When a miner discovers a share, they submit it back to the mining pool for verification. The pool checks whether the share meets the required criteria, such as the current difficulty level set by the Bitcoin network.
Accepted and Rejected Shares: If a share meets the pool’s criteria, it is considered an “accepted share” and contributes to the pool’s overall hashing power. If a share does not meet the criteria, it is considered a “rejected share” and is not counted towards the mining pool’s efforts.
Reward Distribution: The mining pool rewards miners based on the number of accepted shares they contribute. Miners who contribute more computational power and find more shares receive a larger share of the block reward and any associated transaction fees.
Shares play a crucial role in Bitcoin mining as they allow miners to collaborate effectively within mining pools, increasing their collective chances of earning rewards. Additionally, shares provide a measure of a miner’s contribution to the pool’s efforts, which is used to determine their share of the rewards.
Accepted Shares
Accepted shares refer to the computational work done by a miner that meets the pool’s requirements for solving a block. When a miner successfully finds a solution to a portion of the cryptographic puzzle, the pool considers this share valid and adds it to the pool’s work toward solving the block.
Accepted shares contribute to the overall hashing power of the mining pool and increase the likelihood of the pool solving a block and receiving the reward. Miners are rewarded based on the number of accepted shares they contribute to the pool’s efforts.
Rejected shares
Rejected shares are shares that do not meet the pool’s requirements for solving a block. This can happen due to various reasons, such as submitting outdated work, attempting to manipulate the system, or other issues.
When a share is rejected, it is not counted towards the pool’s efforts to solve a block, and the miner does not receive any reward for that particular share. Rejected shares can occur if a miner submits work that is no longer relevant because another miner has already successfully solved the block or if the share does not meet the pool’s difficulty requirements.
Common Reasons for Rejected Shares
Common reasons for rejected shares in Bitcoin mining include stale shares, shares above target (invalid shares), duplicate shares, and other miscellaneous reasons.
Stale Shares: These occur when a share is submitted too late, often due to high latency or connectivity issues. Stale shares can be a result of using a VPN or a slow internet connection. Stale shares are shares that arrive after another miner has already successfully solved the block. Stale shares do not contribute to the pool’s efforts in solving the current block and are therefore rejected. While some degree of stale shares is normal, excessive stale shares can indicate network issues or inefficiencies in a miner’s setup.
Shares Above Target (Invalid Shares): When a miner’s computational output produces a solution that does not meet the target difficulty set by the network, it is considered an invalid share. This can happen due to various reasons, including misconfiguration of mining software, incompatible hardware, or software bugs. Most commonly this is caused by an unstable overclock and can be solved by lower the overclock setting inside your overclocking tool. Invalid shares are rejected by the pool as they do not contribute towards solving the cryptographic puzzle and are essentially wasted computational effort.
Duplicate Shares: Duplicate shares occur when a miner submits the same share multiple times. This can be due to bugs in the mining software or issues with the communication between the miner and the pool. Duplicate shares are rejected by the pool to prevent double-counting of work and maintain the integrity of the mining process.
Other Reasons: This category encompasses any rejected shares that do not fall into the above categories. It could indicate bugs in the mining software, compatibility issues with the mining pool, or other unforeseen issues.
Addressing rejected shares is crucial for miners to optimize their mining operations and maximize their chances of earning rewards. Miners should ensure that their mining software is properly configured, their hardware is compatible with the chosen mining pool, and they have stable internet connectivity to minimize the occurrence of rejected shares. Regular monitoring and troubleshooting can help identify and resolve issues leading to rejected shares, ultimately improving mining efficiency. The most common rejected shares are ‘shares above target’ and ‘stale’ shares.
What is a good accepted/rejected ratio?
A good accepted/rejected ratio in Bitcoin mining can vary depending on several factors, including the mining pool’s specific requirements, the miner’s hardware and software setup, network conditions, and overall mining efficiency. However, in general, miners aim to achieve as high an accepted/rejected ratio as possible to maximize their earnings and minimize wasted computational effort.
While there isn’t a universally agreed-upon threshold for what constitutes a “good” accepted/rejected ratio, miners typically strive a 100% acceptance rate and 0% rejection rate. But this is not always feasible due to the inevitable latency between the miner and the pool stratum server over the long term.
Only stale shares should be considered acceptable, with a tolerance level of up to 1%-2%. Any other rejected share typically indicates a misconfigured system and should be addressed to minimize its occurrence.
NiceHash Rig Manager makes it easy to check the type of rejected share. Simply navigate to the Rig Manager, open rig details by clicking on the rig name and check the mining history stats graph. It will shows the detailed reason for rejected shares.
