Great Consensus Cleanup Revival

A notable method for enhancing this process involves appending a 0 satoshi output with a distinct structure that incorporates an OP_RETURN operation followed by a push instruction to add a nonce. This approach allows miners to adjust the nonce value with minimal impact on the transaction size, necessitating only the final SHA-256 hashing round for updates. Depending on the initial size of the coinbase transaction (excluding the witness data), the additional data required for alignment ranges from 14 to 30 bytes.

Comparatively, alternative strategies like using the nlocktime of the coinbase transaction for nonce purposes also require padding for proper alignment, typically needing an additional 0 to 12 bytes of data. However, if miners are already utilizing an OP_RETURN output for extranonce activities, the extra overhead introduced by this alignment strategy is minimal, ranging from 0 to 4 bytes. When considering the addition of 32 bytes of extra nonce space alongside the standard 32-byte nonce and the 16 bytes afforded by BIP 320, combined with the ability to roll nTime at one-second intervals, the theoretical hash rate capability significantly increases. Specifically, it could reach approximately 1200 zettahash per second (or 1.2 trillion TH/s), representing a thousandfold increase over the current total hash rate. This dramatic enhancement underscores the potential impact of optimizing nonce handling and alignment within coinbase transactions on mining efficiency and output.

Furthermore, the discussion acknowledges practical considerations related to block template configurations in Bitcoin Core, which by default reserves 8000 weight units for coinbase and header operations. While miners have the option to adjust this threshold via the -blockreservedweight parameter, real-world usage, such as by Ocean Pool and Datum users, illustrates varying practices concerning coinbase transaction sizes. Despite the potential for future concerns regarding maximizing block space utilization, the current landscape suggests that the addition of 15 to 31 extra bytes for nonce adjustment would predominantly consume existing safety margins without impacting revenue. This observation highlights the balance between technical optimization strategies and their practical application within the existing mining ecosystem, pointing to the ongoing evolution of practices as miners strive to enhance efficiency while navigating the constraints and opportunities presented by the Bitcoin protocol.