Targets

The nodes an open-loop run sends to, round robin, as a load balancer with passive health checks would (performance item 6): a node whose connection fails is left out for cooldownNanos, then tried again, so a node stopped in a hand-over run gets no more requests until it is back.

An operation whose connection was refused was never sent: it runs again on the next node, its latency still counted from its scheduled time (rerouted counts them). A connection that failed otherwise may have carried the request, which a command does not repeat safely: that operation fails as it did, and its node is left out.