Hiya does Prefect 2 have the concept of heartbeats and the Zombie Killer?

Why are you asking? Did you stumble across some issue that made you think about those concepts? Ideally, you shouldn't have to worry about those as this is more of an implementation detail

I've thought about it too. Our VM agent host went down once and the flows that were in-progress at the time never seemed to get "cleaned up" in the gui, several days later they still reported that they were in progress.

Thanks Oscar, I believe what you're describing is a related but not entirely the same problem of infrastructure crashes. I'm AFK but I'll set a reminder to open an issue for both on Monday. Thanks a lot to you both

Hardly a time-sensitive issue, at least not for me. Otherwise i would have created an issue myself. Appreciated though!

It seems that both use cases are the same: the agent or flow run infrastructure crashes and the flow run and possibly also task runs in progress should be cleaned up (e.g. by setting their state to Crashed/Failed) to give more precise information that the current flow/task runs are in fact no longer Running but Crashed I believe this existing issue addresses that https://github.com/PrefectHQ/prefect/issues/5995, thanks again!