Merged
Conversation
By having an uncancelable fiber via background and discarding the reference to it, the shut down wasn't awaiting the sending process to finish, causing spans to be lost. This bug probably got amplified in newer CE versions with improved performance, it manifested regularly in the Jaeger-based tests, see trace4cats/trace4cats-jaeger#175. I tried adding a test case that would reproduce the issue, but failed as it seems to require real concurrency with thread switches that are hard to set up in a simple test case where as they come naturally from network I/O in integration tests.
ybasket
commented
Jul 18, 2023
| override def complete(span: CompletedSpan.Builder): F[Unit] = | ||
| channel | ||
| .trySend(span.build(process)) | ||
| .flatMap(errorQueue.tryOffer(_).start.void) |
Contributor
Author
There was a problem hiding this comment.
This is not strictly needed to fix the issue, but as tryOffer is guaranteed to never semantically block, I don't see why we couldn't save ourselves from the overhead of starting a fiber on this relatively hot path.
gbastkowski
approved these changes
Jul 18, 2023
This file contains hidden or 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
2 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
By having an uncancelable fiber via background and discarding the reference to it, the shut down wasn't awaiting the sending process to finish, causing spans to be lost. This bug probably got amplified in newer CE versions with improved performance, it manifested regularly in the Jaeger-based tests, see trace4cats/trace4cats-jaeger#175.
I tried adding a test case that would reproduce the issue, but failed as it seems to require real concurrency with thread switches that are hard to set up in a simple test case where as they come naturally from network I/O in integration tests.