Solana activates Alpenglow, targeting 150ms finality
Solana activated Alpenglow on Oct. 21, replacing its voting system and targeting 150ms finality; users keep their wallets, while actual speeds may vary.
The Blockheight Editors··2 min read
Solana activated its Alpenglow consensus upgrade on Oct. 21, replacing the voting system it has used since 2020 and targeting transaction finality in about 150 milliseconds, according to the Solana Foundation’s upgrade notes. Finality is when a transaction can no longer be reversed, which could let exchanges credit deposits and merchants confirm payments sooner.
How does Alpenglow change transaction settlement?
Alpenglow changes how validators agree on blocks. Under the old TowerBFT system, validator votes were recorded as transactions and approvals accumulated across blocks; with Alpenglow, validators send votes directly to one another and combine them into certificates, allowing a block to become final after one or two voting rounds.
The target is about 150 milliseconds, down from 12.8 seconds under TowerBFT, the Solana Foundation says. CoinDesk reported that the switch took about 900 milliseconds, with votes from 446 of 654 participating validators certifying the starting block.
What changes for people using Solana apps?
Users can keep their existing wallets, and transaction fees and application behavior remain unchanged, according to Solana’s upgrade notes. CoinDesk reported that quicker finality could allow an exchange to credit a deposit sooner or a shop to confirm a stablecoin payment with less waiting.
The 150-millisecond figure is a target under normal network conditions, not a guarantee for every transaction. How soon users see finality also depends on the service handling the payment, CoinDesk reported, citing Anza, the company behind Solana’s Agave software.
Why could Solana’s transaction counts fall?
Validator votes no longer appear as on-chain transactions, so dashboards that counted them may show lower transaction totals even if user activity has not fallen, CoinDesk reported. The Solana Foundation also says execution, transaction formats and fees are unchanged.
Alpenglow’s Votor voting protocol is live; the Foundation says Rotor, a planned change to how block data spreads across the network, has no release schedule yet. The 150-millisecond target and its effect on user-facing services remain to be seen in practice.
Source material
- Solana Foundation’s upgrade notes — solana.com