This feature is highlighted within the Bitcoin Core documentation, specifically under the command line options where the -blockreconstructionextratxn parameter is detailed. It denotes the number of extra transactions that are retained in memory to aid in the reconstruction of compact blocks, with the default setting being 100 transactions. This mechanism is distinct from the variations in mempool sizes across different nodes or peers, which might also impact network performance but are considered more effectively analyzed through simulation tools like Warnet rather than direct observation on the mainnet. This differentiation underscores a targeted approach to optimizing blockchain efficiency and reliability, emphasizing the importance of internal mechanics like the extra transaction pool in maintaining the integrity and speed of block reconstructions on the Bitcoin network.