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There was a tricky race condition in compute_ctl, that sometimes makes configurator skip updates. It makes a deadlock because: - control-plane cannot configure compute, because it's in ConfigurationPending state - compute_ctl doesn't do any reconfiguration because `configurator_main_loop` missed notification for it Full sequence that reproduces the issue: 1. `start_compute` finishes works and changes status `self.set_status(ComputeStatus::Running);` 2. configurator received update about `Running` state and dropped the mutex lock in the iteration 3. `/configure` request was triggered at the same time as step 1, and got the mutex lock 4. same `/configure` request set the spec and updated the state to `ConfigurationPending`, also sent a notification 5. next iteration in configurator got the mutex lock, but missed the notification There are more details in this slack thread: https://neondb.slack.com/archives/C03438W3FLZ/p1727281028478689?thread_ts=1727261220.483799&cid=C03438W3FLZ --------- Co-authored-by: Alexey Kondratov <kondratov.aleksey@gmail.com>