Expand description
The durable timer wheel: absolute
deadlines owned by a step, a tool request, a start node or the lifecycle;
armed through the store, fired by the loop’s tick (fire), re-armed from
the restored records at startup (past deadlines fire immediately).
The durable row outlives the firing: fire hands the record to the loop and
only settle — at the head of the next tick’s fire, i.e. after the tick
that ran the effect has checkpointed — deletes it. See Timers::fire for
why that ordering is the only crash-safe one.