I know that covert asicboost can't be used anymore after segwit.
However, I'm studying it to understand how it worked. I hope you can help me because I am confused.
In particular, I'm studying this doc...
https://arxiv.org/ftp/arxiv/papers/1604/1604.00575.pdfThis is the normal mining process (which you are familiar with but which I summarize for completeness) according to that document:
1. in the header there are two chunks
2. the first chunk is modified about once every four billion attempts (maybe even less frequently since we can play with time a bit...but let's not quibble)
3. the second chunk is modified on each attempt by changing the nounce
4. for each chunk an expansion and a compression process is performed
5. the expansion of the first and second chunks are independent of each other
6. on the contrary, the compression of the two chunks must be done in order: first the first, then (starting from the compression of the first) the second
7. then a phase of expansion + compression of the obtained hash (second hash).
8. finally the evaluation of the last hash obtained, to see if it is less than the target
this loop repeats until a hash lower than the target is found. It is not necessary to waste hash power to do the expansion+compression of the first chunk at each attempt: you can 'freeze this process in a 'mid state': at each attempt (that is, at each increase of the nounce) you just do:
(1) chunk expansion 2
(2) chunk compression 2
(3) hash expansion obtained
(4) hash compression obtained
image at page 5 is perfect to show the 4 steps aboveWith asicboost, you hold the second chunk and only modify the first one (never mind how this was actually done)
this is what I DON'T UNDERSTAND:image at page 6 is good to show thisaccording to this figure, 3 steps are taken for each attempt: 2 compressions and one expansion.
But, in my opinion, the 'mid state' assumes an expansion+compression of chunk 1, which with asicboost changes with each attempt (instead of chunk 2 as in normal mining)
therefore, with the asic boost, 5 steps are made at each attempt, and not 3 as the text that I linked says: the 3 that the text says + an expansion + compression for the mid state
so asicboost would be less efficient than normal mining (4 steps).
obviously I misunderstood, and asic boost was not working as it seems to me. I'd like to understand where I'm wrong. I hope I was clear enough and asking a lot but not too much. Thank you!
