04-23-2024, 11:25 AM
(04-23-2024, 04:45 AM)kindongsy Wrote: If optimizations have been made in SHA2 software implementations for bitcoin mining, it might be possible to compare these within an environment like Hashcat, don't you think?
Actually, it's the other way around. Hashcat can probably hash in less steps than mining can because we have a target hash and parts of the hash can be reversed a few steps. Mining has to just do it fully because there isn't any "target", it's just trying to find low value hashes. In the optimisations list, this is called "Early Skip" where we can tell mid-way that a hash won't turn out to be the one we're looking for, however this has limitations in Hashcat and is only enabled with a single target hash.
"Early Skip" is this if statement here:
https://github.com/hashcat/hashcat/blob/...ed.cl#L282
Unfortunately SHA256 is one of the weaker implementations of this optimisation. Other algorithms like MD4/MD5/NTLM are way, way more impactful and can skip huge parts of the hashing process most of the time