Squash allocations in selector parsing and other hotspots #9564
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
marvin-tigera
added
release-note-required
fasaxc
force-pushed
the
squash-allocs
branch
2 times, most recently
from
e57d003 to
51d7220
Compare
fasaxc
added
docs-not-required
Reduce usage of WithFields on the hot path; it allocates heavily.
mazdakn
approved these changes
Dec 12, 2024
| log.Debug("Remaining input: ", input) | ||
| } | ||
| startLen := len(input) | ||
| input = strings.TrimLeft(input, whitespace) | ||
| input = trimWhitespace(input) |
There was a problem hiding this comment.
I assume we can do this because of the limited charset we recognise, right? But what's the main motivation it?
There was a problem hiding this comment.
Yes, I think TrimLeft was allocating/doing work to calculate the cut set so this was faster.
| ) | ||
| func (t Token) String() string { | ||
| return fmt.Sprintf("%s(%s)", t.Kind, t.Value) | ||
| } | ||
|
|
||
| // Tokenize transforms string to token slice | ||
| func Tokenize(input string) (tokens []Token, err error) { |
There was a problem hiding this comment.
nit: no need for named return values.
| if len(input) > 1 && input[1] == '=' { | ||
| tokens = append(tokens, Token{TokEq, nil}) | ||
| input = input[2:] | ||
| if input, found = strings.CutPrefix(input, "=="); found { |
There was a problem hiding this comment.
Using CutPrefix is definitely easier to read. But I wonder why here we move to a cleaner version, while for TrimLeft the decision is to implement a new function?
|
/merge-when-ready squash-commits |
|
OK, I will merge the pull request when it's ready, squash the commits when I merge it, and leave the branch after I've merged it. |
sridhartigera
pushed a commit
to sridhartigera/calico
that referenced
this pull request
Dec 18, 2024
…ico#9564) * Squash some chatty allocations. Reduce usage of WithFields on the hot path; it allocates heavily. * Avoid allocations when validating selectors. * Clean ups in tokenizer. * Tweaks. * Markups.
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.
Description
Noticed that selector parsing was a memory allocation hotspot in clusters with lots of policy. Most of that was down to validating selectors so we were just throwing away the parsed selector.
tokenizer.AppendTokens()to do tokenization into a pre-allocated buffer. Use a shared instance of the parser to hold the shared token buffer (protected my mutex).strings.Cutand friends; makes for easier reading and less string slicing.Before:
After:
Related issues/PRs
CORE-10829
Todos
Release Note
Reminder for the reviewer
Make sure that this PR has the correct labels and milestone set.
Every PR needs one
docs-*label.docs-pr-required: This change requires a change to the documentation that has not been completed yet.docs-completed: This change has all necessary documentation completed.docs-not-required: This change has no user-facing impact and requires no docs.Every PR needs one
release-note-*label.release-note-required: This PR has user-facing changes. Most PRs should have this label.release-note-not-required: This PR has no user-facing changes.Other optional labels:
cherry-pick-candidate: This PR should be cherry-picked to an earlier release. For bug fixes only.needs-operator-pr: This PR is related to install and requires a corresponding change to the operator.