Solana schedules Alpenglow for Oct. 21 with 150ms target

150 milliseconds is the finality target for Solana’s Alpenglow upgrade, scheduled for Oct. 21. If it reaches that target, a transaction could become irreversible much sooner than under the network’s current system, which takes about 12.8 seconds. CoinDesk reports that the change will replace TowerBFT, Solana’s existing validator voting system.

What changes when Alpenglow activates?

Alpenglow replaces TowerBFT with a new consensus protocol called Votor, which changes how validators agree that a block is final. Anza, the Solana development team, says the upgrade is scheduled to go live on mainnet-beta at about 14:50 UTC on Oct. 21, according to CoinMarketCap’s report on Anza’s announcement.

Today, validators record their votes as transactions on Solana. Under Alpenglow, they will send signed votes directly between one another instead. The votes can form a certificate that marks a block as final, freeing the space those vote transactions used in blocks.

The new system can finalize a block in one voting round if validators representing 80% of stake respond, or in two rounds if 60% respond, Anza says. Stake is the SOL committed by validators and their delegators to help secure the network.

How will the network switch systems?

The change is planned as a handoff on the running network, after a feature gate activates at an epoch boundary. Five thousand slots later, blocks stop carrying user transactions while validators establish an Alpenglow genesis block; the handoff follows once enough stake has signed off.

CoinMarketCap reports that Anza expects the handoff itself to take hundreds of milliseconds. During the transition, user transactions may wait briefly while validators move consensus to Votor. Anza has already rehearsed the migration on a community cluster, testnet and devnet.

The 150-millisecond figure is a target, not a guarantee for every transaction. CoinDesk notes that actual finality will depend on network conditions. Faster finality could let an exchange, merchant or bridge rely sooner on a payment being settled, but the result will depend on how the network performs after activation.

What should you watch after the upgrade?

Solana’s reported transaction count may fall when validator votes stop appearing in blocks, even if user activity stays steady. A lower headline count would therefore not, by itself, show that fewer people are using the network.

Validator operators also need to prepare their software. CoinDesk reports that validators must use software built on Agave 4.3.0 for the migration, while operators running Firedancer or Frankendancer will need to switch clients temporarily because those alternatives will not support the initial handoff.

For you as a wallet user, the announcement describes a change to how the network confirms transactions, rather than a new way to send one. The key test comes after Oct. 21: whether Alpenglow delivers its faster finality target under live network conditions.

Sources

• CoinDesk reports — coindesk.com
• CoinMarketCap’s report on Anza’s announcement — coinmarketcap.com