Solana to launch Alpenglow upgrade on Wednesday, transaction finalization time expected to be reduced to 150 milliseconds.

Solana to Launch Alpenglow Upgrade on October 21, One of Network’s Largest Underlying Overhauls Since 2020 Solana will roll out its Alpenglow upgrade on October 21, marking one of the most significant foundational overhauls the network has undergone since 2020. The upgrade will replace the existing validator voting mechanism, aiming to cut transaction finalization time from roughly 6 seconds to 150 milliseconds—an approximate 40x speed boost. At the core of the upgrade is shifting validator voting from on-chain to off-chain, consolidating votes into certificates that enable transaction finalization within 1 to 2 consensus rounds. If mainnet performance meets expectations, Solana’s transaction confirmation speed will approach that of credit card payments or centralized exchanges, enhancing user experiences for meme coin trading, stablecoin payments, and on-chain platforms. The upgrade will also reduce validator costs. Currently, validators pay around 2 SOL in daily voting fees. Post-upgrade, voting fees will be eliminated, replaced by a fixed validator access fee per epoch: 0.8 SOL per ~24-hour epoch, an estimated cost reduction of roughly 60%. However, the testing process faced hurdles. According to Galaxy Digital, since the testnet launched in early May, it has been wiped and restarted from scratch six times. One migration attempt caused a full testnet failure requiring a rollback; subsequent migrations ultimately succeeded, paving the way for the mainnet launch. All issues occurred on the testnet, with no impact on real funds. Per the announcement, the upgrade will begin at the start of Epoch 1064 on Wednesday, and complete the switch at Slot 459,653,000 after a 5,000-slot transition phase.