Reduce lock usage during EditDistance.GetEditDistance and BKTree.Find #75610
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 SimplePool and ArrayPool classes previously used always locked on Allocate/Free which is showing up in a trace David Kean referred us to. Instead, as the char arrays being allocated are typically quite small, utilize the stack for these temporary char array locations when possible, falling back to heap allocating in the rare occasions where it's not.
dotnet-issue-labeler
bot
added
Area-IDE
untriaged
CyrusNajmabadi
approved these changes
Oct 24, 2024
| lowerCaseCharacters[i] = CaseInsensitiveComparison.ToLower(value[i]); | ||
| Span<char> lowerCaseCharacters = value.Length < 512 | ||
| ? stackalloc char[value.Length] | ||
| : new char[value.Length]; |
There was a problem hiding this comment.
I would still use the pool for large strings.
There was a problem hiding this comment.
Just here, or in EditDistance too? I'm not sure about here, but I wouldn't think the EditDistance code would almost ever exceed 512 chars.
There was a problem hiding this comment.
Just to make sure, I don't think the old code was pooling large strings, as ArrayPool checked against MaxPooledArraySize for both retrieving and returning from the pool.
This was referenced Oct 29, 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Outdated suggestions cannot be applied.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.
The SimplePool and ArrayPool classes previously always locked on Allocate/Free which is showing up in a cpu usage in a trace David Kean referred to us. Instead, as the char arrays being allocated are typically quite small, utilize the stack for these temporary char array locations when possible, falling back to heap allocating in the extremely rare occasions where it's not.
Below is the cpu usage that David pointed us to:
