fixes a possible race condition in AutoRestartTrick #1002
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Just a long shot for a failure observed on #998. My hypothesis is that when we stop ProcessWatcher before we restart the process manually, we don't yield to it and immediately kill the process. Next, when the ProcessWatcher thread is woken up, we have to conditions ready - the popen_obj and stopped_event, see the corresponding code,
And despite that
stopped_event
is set, we first check forpopen_obj
and trigger the process restart.We can
alsomake the ProcessWatcher logic more robust, by checking if we are stopped before calling the termination callback, e.g.,I am not 100% sure about that, as I don't really know what semantics is expected from ProcessWatcher by other users. But at least the AutoRestarter expects this semantics - i.e., a watcher shall not call any events after it was stopped.