What happened

IOG added a resume-from-persisted-data mode to the Leios dozen-devnet and proto-devnet. Instead of restarting from an empty chain, the devnets can keep their working directories across restarts.

The node readiness-probe timeout was also raised to ninety minutes, or 5,400 seconds. The record says replaying roughly ten hours of chain can take about fifteen minutes, and the longer window is intended to prevent that replay from being treated as a crash.

Why it matters

The stated target is behaviour that appears only once Leios databases become large. Keeping a large cluster’s on-disk state between runs gives the devnets a way to reach and inspect that regime, rather than repeatedly beginning from an empty chain.

This is therefore an enabling change for the ongoing Leios database-at-scale investigation. It does not report a throughput result, a performance figure, or a conclusion about how Leios will behave outside these devnets.

What to watch

The next useful receipt would be findings from the large-database testing: how nodes behave once persisted state is substantial, and whether the resume path works reliably enough for that investigation. Any report should distinguish testing observations from broader readiness claims.

The available feed is thin and dev-only. It contains Leios commits from a single primary feed, with no independently corroborated news or press items, so this update is best read as a development-track signal.

What to watch

Watch for published findings from Leios database-at-scale testing, including cases where resumed nodes need to resync.

Sources and limits

Upstream references and independent checks

Digest dated 2026-08-29 · upstream model claude-sonnet-4-6. Direct links are matched to all 3 upstream source IDs.

  1. 1
    dozen-devnet: allow resuming a cluster from persisted dataDirect upstream source · 541e6ae4cf6d46ecb9ae0865b786721e4ba330a6
  2. 2
    dozen-devnet: stop the readiness probe from killing replaying nodesDirect upstream source · d8eae0d1995118ef871c64efe39a7a5cdc555b62
  3. 3
    Allow resuming proto-devnet from existing dataDirect upstream source · f05362f8e4ce7cdf24f24fb7a0f4ca0adc0483b0

This Research brief was generated by Terra from a dated upstream research digest. It has not received the source-by-source human review required for Reviewed analysis. Material limit: This is a single-source, devnet-only update. Resume is explicitly best-effort, has no Leios DB schema migration, and some nodes may still require resynchronization.