Hi all, I have a flow run that I cancelled which still has a task that appears to be running for over 3 hours now, is there any way to force kill this through the UI?

Yeah so the cancellation is a best effort thing, but Python makes it hard to cancel other processes, especially happening on different compute. So if the cancel in the UI doesn’t work, then yes you likely have to kill it yourself

Piggybacking off this thread. I had the same issue and several flows are still showing as “cancelling” in the UI after several days. The latest log entries for all flows are

Flow run RUNNING: terminal tasks are incomplete.

I have confirmed all pods associated with the Flows have been terminated. Can I discount it as a quirk of the Prefect UI?

This backend service for this is being investigated to make it more stable. The goal is to eventually mark it as failed after some time. In the meantime, you could just set it to failed yep.