we investigated an issue that corresponded to a trial server receiving too many requests per second.
What happens in this case is that Opentracker queues the requests, but does not process them to red/ green puppets.
The visitors are then added to visitor counts, reports, etc, but not added in real-time as puppets.
Advantage: no data lost when too many requests per second are received
Disadvantage: no red / green puppets in real-time.
Resolution: server will be monitored more closely, and/ or server will be upgraded.