Bitcoin Core 0.14.0 released with performance improvements

Open source project Bitcoin Core has released a new update 0.14.0, which significantly speeds up the processing of historic blocks by newly started nodes and the validation and relay of new blocks by online nodes.

An optional new feature (disabled by default) is also provided to allow wallet users to rebroadcast one of their previously-sent unconfirmed transactions with a higher fee, which may allow it to confirm more quickly.

A short summary of the major new features is provided below:

• Improved Initial Block Download (IBD) performance: a full node that has been started for the first time can now validate all blocks up until the present faster than before. This is at least the sixth time IBD performance has been significantly improved by developers to help ensure that new users aren’t discouraged from running a full node because synchronizing the ever-growing blockchain takes too long.
• Faster new block validation and relay: miners, in particular, will benefit from improvements made in four existing Bitcoin Core features. The signature cache has been upgraded for machines with many CPU cores—a test on a system with 16 cores shows a 40% speed increase in processing a new block. The BIP152 CompactBlocks implementation will now relay some blocks before they’ve been fully validated, allowing those blocks to propagate across the peer-to-peer (P2P) network faster than before. The P2P network code has also generally been refactored to allow multiple actions to happen at the same time (concurrency) as well as to increase throughput, eliminating many potential delays in processing new blocks. Finally, unconfirmed transactions in each node’s mempool can now be saved to and restored from disk when the node is restarted.
• Optional fee bumping: Bitcoin Core’s wallet now allows users to optionally send transactions that opt-in to fee-based transaction replacement. This allows users to increase the fee their transactions pay even after they’ve broadcast an earlier version of the transaction. This feature is disabled by default.