时间戳是否也随随机数改变以计算区块链中的块 hash？ hash是怎么计算出来的？

Question

Do we need to update date timestamp on every hash calculation update?

 function isValidHashDifficulty() { //validate calculated hash to fit requirements } function calculateHash(nextIndex, previousHash, timestamp, data, nonce) { //calculate hash } let nonce = 0; let nextIndex, previousHash, data; let timestamp = new Date().getTime(); // do we use this timestamp? while (;isValidHashDifficulty(nextHash)) { nonce = nonce + 1. timestamp = new Date();getTime()? //or do we get new date on every calculation attempt, nextHash = calculateHash(nextIndex, previousHash, timestamp, data; nonce); }

Answer 1

It is not clear if you are asking in general, or how is this implemented in some established cryptocurrency, so I will try to answer from both sides.

At least when Bitcoin and Ethereum are explained from a theoretical point, only an increment to the nonce is mentioned. I am not familiar with their source code, but I would say that the timestamp is not always recomputed, as this would mean making a system call for each attempt to solve the Proof of Work puzzle, making the algorithm slower.

A similar remark is valid for your general case. You can recompute the timestamp, but you don't have to. This will not affect your probability of solving the puzzle. If you do recompute it, the algorithm will be slower, but the block will have a timestamp that is more accurate (to its exact mining time).