Timeline
- 8.5
Solana consensus upgrade Alpenglow to go live on mainnet on October 21, cutting finality to about 150 milliseconds
Anza, Solana's core development team, announced that the Alpenglow consensus upgrade is scheduled to activate on Solana mainnet-beta around October 21 at 22:50 (UTC+8, roughly 14:50 UTC), with the migration to be completed within a single slot. Alpenglow replaces TowerBFT, the consensus protocol Solana has used since genesis, and is intended to cut transaction finality from seconds to about 150 milliseconds. Anza says moving voting off-chain frees block space for user transactions, and that faster finality shortens settlement for institutions from the usual 1–3 business days to roughly 150 milliseconds. It is described as the most significant change to Solana's core consensus since the network launched. Anza developed Alpenglow over 18 months; it was previously migrated on testnet (September 24) and devnet (September 25) and tested in a 1,500-node simulation, with a bug bounty exceeding 25,000 SOL. Under the new Votor voting protocol, validators exchange votes directly instead of submitting them as on-chain transactions, which the announcement says could cause a significant decline in reported transaction totals that include validator votes.
- 7.5
Solana doubles block production speed to 200ms as network prepares for Alpenglow upgrade
Solana activated 200-millisecond slots on mainnet, halving its original 400-millisecond block-production target and raising block-production opportunities to five per second instead of 2.5. Anza, the developer behind the Agave validator client, confirmed the SIMD-0525 upgrade, which also shortens a network epoch to about 24 hours from 48 hours. Shorter intervals could improve transaction responsiveness for applications on Solana, particularly decentralized trading platforms and market makers that depend on rapid price and order updates. The upgrade does not automatically double transactional capacity, because the computational budget available within each slot was proportionally reduced. Under SIMD-0525, each validator's nominal four-slot block-production window fell to 800 milliseconds from 1.6 seconds, and transaction blockhashes now expire in roughly 30 seconds instead of 60. CryptoSlate's sampling of Solana's public mainnet RPC showed an average of about 222 milliseconds across 1,413 slots after activation, compared with roughly 268 milliseconds under the previous 250ms target.