Crypto · updated 1h ago · 2 min read
Solana’s Alpenglow Upgrade Reaches Second Public Test Network With 150ms Finality Target
Alpenglow moved to public testnet/devnet for pre-mainnet testing Target finality around 150 milliseconds, down from roughly 12.8 seconds
12 outlets told this the same way.
2 of 3 outlets skipped it: alpenglow removes validator votes from blocks, affecting data charts.
12outlets compared
Alpenglow hits devnet
Solana’s Alpenglow upgrade reached its second public test network, with Alpenglow running on both devnet and testnet so application teams can check their software before any live blockchain switch.
Anza announced the developer-network switch on Sept. 25, a day after the separate testnet completed its transition, and the Solana Foundation’s upgrade page lists Alpenglow as active on both networks.
Alpenglow targets roughly 150 milliseconds for finality, the point at which a transaction can no longer be reversed, compared with about 12.8 seconds under the existing system.
Alpenglow changes how validators reach agreement by removing validator votes from blocks, and it will exchange votes directly instead of recording those votes as transactions inside blocks.
The Foundation has told data providers to adjust comparisons because transaction totals that include validator votes will shrink even if user activity remains unchanged.
How finality changes
Under Solana’s current TowerBFT system, validators vote by sending vote transactions that are included in blocks, and finality takes about 12.8 seconds because enough validator votes must accumulate across multiple slots. Alpenglow’s Votor system removes those votes from blocks, and validators communicate their votes directly and aggregate them into cryptographic certificates showing that sufficient stake has agreed on a block. A block can then become final after one or two voting rounds, and the Foundation says a block can reach finality after one voting round if validators representing at least 80% of stake vote to accept it.
The upgrade does not change how Solana executes transactions, because the Solana Virtual Machine, transaction formats, fees, and programs remain unchanged. The Foundation separates finality from the time it takes to produce a block, and the 150-millisecond figure remains a target derived from simulations rather than a demonstrated result under live-market conditions.
What it could unlock
Solana’s Alpenglow rollout is designed to shorten the wait for exchanges to release deposited funds and for payment apps to notify a merchant a sale is complete once a transaction reaches finality.
The upgrade’s faster finality could also affect how U.S. exchanges decide when to credit a Solana deposit, and how payment providers decide when to treat a merchant’s sale as complete.
The Foundation says applications that simply send transactions and read account balances require no migration, but block-data services must update their systems because Alpenglow can expose competing candidate blocks for the same slot before the network selects one.
The Foundation tells data providers to keep those candidates separate, and it warns that mixing their contents could produce an incorrect record.
Anza’s software schedule tentatively allows feature activations to resume Sept. 28, but it does not identify that date as Alpenglow’s launch, and no firm launch date has been announced for the live network.