array: avoid overallocation when inserting at beginning of empty arrays #59717
Conversation
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
oscardssmith
reviewed
Oct 1, 2025
oscardssmith
approved these changes
Oct 1, 2025
|
@nanosoldier |
|
Your benchmark job has completed - possible performance regressions were detected. A full report can be found here. |
|
Nanosoldier results seem noisy as expected. (allocations mostly down, runtime slightly up for some, slightly down for others). |
maxsize is usually typemax, so need to be careful to not do comparisons after adding to it. Substracting from it should normally be perfectly fine. At worst we should compute a negative amount of space remaining.
Fixes a minor nuisance where length 0 would grow to 8 and length 7 would also grow to 8. Instead growing by a flat 3x even initially. Fixes #58640
KristofferC
removed
the
backport 1.12
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 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Outdated suggestions cannot be applied.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.
array: reduce overallocation when inserting into small arrays
Fixes a minor nuisance where length 0 would grow to 8 and length 7 would also grow to 8. Instead growing by a flat 3x even initially.
Fixes #58640