Concurrency cancellation #2090
Merged
Concurrency cancellation #2090
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
aron
force-pushed
the
concurrency-cancellation
branch
from
409b659 to
cc8d97a
Compare
|
Hmm, I've broken the sync tests somewhere, putting this back into draft while I figure it out. |
Currently a cancellation event sent to a worker with `concurrency` > 1 will always cancel the most recent task. This commit refactors the `_ChildWorker` class to exclusively send the `Cancel` event when receiving a `CancelRequest` and then handle the cancellation in the event loop. For the async `_aloop` we now use a weak map to track all in flight prediction tasks. On cancel, we retrieve the task from the map and cancel it. For the standard `_loop` method we send the cancellation signal to the process as before. It's not entirely clear why the child needs to send the signal to itself vs raising the `CancellationException` directly but this commit leaves it as-is for simplicity.
aron
force-pushed
the
concurrency-cancellation
branch
from
cc8d97a to
d4f5e70
Compare
|
I had an accidental |
philandstuff
approved these changes
Dec 18, 2024
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Outdated suggestions cannot be applied.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.
Currently a cancellation event sent to a worker with
concurrency> 1 will always cancel the most recent task.For the async
_aloopwe now use a weak map to track all in flight prediction tasks. On receipt of aCancelevent, we retrieve the task from the map and cancel it.For the standard
_loopmethod we continue to ignore theCancelevent. Relying on calling thesend_cancel_signal()to terminate the worker method before sending theCancelevent. I'm not 100% clear on why the parent needs to do this but callingsend_cancel_signalor raisingCancelationExceptiondirectly in the_loopmethod causes the tests to fail so I've left it as-is.