Claim timing: TTL floor and silence timeout

Why claims have timers

When a tractor claims a stop, that stop is reserved for it so no other machine double-books the property. Two tunables decide how forgiving that reservation is, and they're the levers behind Snowmass's self-healing behaviour.

Claim TTL floor

A claim's time-to-live scales with the travel time to that stop — roughly twice the estimated travel — so a far stop stays reserved longer than a close one. The TTL floor is the minimum a claim will ever live, in seconds, no matter how close the stop is. Bounds are 60 to 7200 seconds (1 minute to 2 hours).

• Lower the floor on dense residential routes where stops are seconds apart and you want a stalled tractor's work reclaimed quickly.
• Raise the floor on sparse routes with long drives, so a claim isn't dropped while a tractor is legitimately still en route.

Silence timeout

The silence timeout is how long a tractor can stop reporting GPS before its claims become eligible to be released back to the swarm. Bounds are 60 to 3600 seconds (1 minute to 1 hour); the practical default is around 5 minutes. A dropped tablet, a dead battery, or a machine parked in a dead zone will trip this, and the background reclaim job (runs every 60 seconds) hands that work to a live tractor.

Choosing values

The defaults suit most fleets. Tighten both on high-density urban routes for faster recovery; loosen them where long, legitimate silences (rural drives, parkade dead zones) are normal and you don't want work yanked away prematurely.