Solana to Activate Alpenglow Upgrade on Oct. 21, Speeding Transaction Finality by 40 Times

Solana plans to implement a major network upgrade called Alpenglow that would cut transaction finality time from 6 seconds to 0.15 seconds.

CoinDesk reported on Oct. 21 that Solana is set to deploy the Alpenglow upgrade to its mainnet that day. If the upgrade performs as intended, transaction finality will shrink to about 150 milliseconds, or as much as 40 times faster than before.

At the core of Alpenglow is a change in how validators verify transactions and reach consensus. Under the current system, validators record votes directly on the blockchain, and transactions are finalized only after sufficient agreement is reached. The new system moves voting off-chain and bundles the results into certificates, allowing transactions to be finalized after just one or two rounds of consensus.

Shorter finality times could improve processing efficiency for decentralized exchanges, or DEXs, and stablecoin payment services. The current 6-second finality window can cause delays in fast-moving markets. If Alpenglow works as designed, Solana could deliver processing speeds closer to centralized exchanges and card payments.

Validator operating costs will also fall. Solana validators currently spend about 2 SOL a day on voting fees. Alpenglow would eliminate those fees and instead charge a fixed participation fee of 0.8 SOL per epoch, or about every 24 hours. That would reduce related costs by about 60%.

The upgrade process, however, was marked by repeated technical issues. Galaxy Digital said the network was reset and restarted six times after testnet operations began in early May. In one attempt to switch to the new consensus system, the full network migration failed and was rolled back. A subsequent retry succeeded, completing the process required for the mainnet rollout.

Alpenglow is scheduled to be activated in Epoch 1064, which begins on Oct. 21. The actual transition will occur after a 5,000-slot migration period at slot height 459,653,000. Whether the 150-millisecond finality target can be delivered reliably on mainnet will only be clear after the upgrade goes live.