Solana cuts mainnet slot time to 350 milliseconds

Solana completed a mainnet upgrade that reduced its target slot time to 350 milliseconds from 400 milliseconds. A slot is the period when a designated validator can produce a block. The change is the first step under SIMD-0525, which was merged on May 14. SIMD-0525 outlines three further 50-millisecond reductions toward a 200-millisecond target. Each reduction will activate separately. The rollout can pause if too many validators fail to produce assigned blocks. Epochs contain 432,000 slots. Epochs are expected to shorten from about 48 hours to about 42 hours. Validators will change turns every 1.4 seconds instead of every 1.6 seconds. A point-in-time check found that 1,000 slots took 415 seconds before the change and 368 seconds afterward. Shorter slots reduce confirmation and finalization latency. The change does not automatically increase the network's processing capacity per second. The next planned slot-time target is 300 milliseconds, but developers have not set an activation date. Solana's Alpenglow overhaul aims to reduce full finality to about 150 milliseconds from roughly 12.8 seconds.