9 Intermittent missing quadkey value #10
Merged
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
The identifiers.SortIdentifiers() function is passed a list of strings which it sorts internally, creating a race condition when this function is called concurrently with the same list. (And it would be called concurrently in practice, and is always passed the same list.) The author of the function appears to have intended to make a copy of the list to avoid this, but the "copy" was just a new slice pointing into the old slice.
captaincoordinates
approved these changes
Jul 9, 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Outdated suggestions cannot be applied.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.
Closes #9
I was not able to duplicate this issue but I did find a race condition the definitely could have produced the observed issue.
allIdentifiers[:]does not copy the underlying array like[:]does in Python, it just creates a new slice that points the same underlying array asallIdentifiers. Soidentifiers.SortIdentifiers()was still sorting the elements inallIdentifiersdespite the apparent attempt to make a copy.This could definitely cause keys to go missing if requests are handled concurrently. You would have multiple handlers attempting to sort the same array at the same time.