Add workers graceful timeout - test refactor #459
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
Follow-up from #435, just to demonstrate a possible refactoring
Granian uses multiprocessiong to keep track of workers. On respawn and stop it uses
SIGTERMtogether withjoinwithout atimeout(althoughtimeoutis exposed). If a worker refuses to gracefully stop, the granian main loop can get stuck at thejoinThis change implements a timeout for graceful stopping of workers with a default of
30s. If the timeout is breached the worker gets force stopped usingSIGKILL. The timeout can be changed with--workers-graceful-timeouton the cmdline or as parameter in an app.Related work: gunicorn
Reproduction: The issue can be simulated by starting a thread in a worker without daemonizing it:
threading.Thread(target=slow_thread).start(). If granian is used together with FastAPI it also works with a background task:background_tasks.add_task(slow_task). Note: The thread or task doesn't have to be hanging, but just has to be running at the time granian tries to stop the worker.