Solana activates Alpenglow, cutting transaction finality to ~150ms

Solana activated its Alpenglow consensus upgrade on mainnet on October 21, 2026, replacing TowerBFT at slot 459,653,000. The Votor protocol targets finality of about 150 milliseconds, down from roughly 12.8 seconds — a reduction of nearly 99%. Confirmed and finalized now represent the same consensus state, changing how RPC infrastructure and data streaming handle transactions.

• Finality cut from ~12.8s to a ~150ms target, nearly 99% faster
• Alpenglow replaced TowerBFT on mainnet on October 21, 2026
• Confirmed and finalized now reflect the same consensus state
• 150ms is a consensus target, not RPC request latency