Delivery Assurance: Durable Collision

Each standard durable can serve at most one durable subscriber object at a time. The persistence store resolves collisions in favor of the most recent durable subscriber.

For example, if a durable subscriber in process A is using durable D, and a new durable subscriber in process B subsequently claims D, then B wins the durable from A. The persistence store forces subscriber A to close.

The assumption behind this behavior is that the older durable subscriber is malfunctioning, and the newer one has started in order to replace it.

Collision does not apply with shared durables or last-value durables, both of which can support more than one subscriber at a time.

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