Skip to content

perf(codegen): reduce memory usage in SourcemapBuilder #13679

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
graphite-app merged 1 commit into from
Sep 11, 2025
Merged

perf(codegen): reduce memory usage in SourcemapBuilder #13679

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
9 changes: 6 additions & 3 deletions crates/oxc_codegen/src/sourcemap_builder.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -307,9 +307,12 @@ impl<'a> SourcemapBuilder<'a> {
let mut lines = vec![];
let mut column_offsets = IndexVec::new();

// Used as a buffer to reduce memory reallocations
// Pre-allocate with reasonable capacity to avoid frequent reallocations
let mut columns = Vec::with_capacity(256);
// Used as a buffer to reduce memory reallocations.
// Pre-allocate with reasonable capacity to avoid frequent reallocations.
// 16 is a guess, probably adequate for most files which don't heavily use unicode chars.
// 16 entries is 64 bytes = 1 CPU cache line on most CPUs.
// If file does heavily use unicode chars, `columns` will grow adaptively as needed.
let mut columns = Vec::with_capacity(16);

// Process content line-by-line.
// For each line, start by assuming line will be entirely ASCII, and read byte-by-byte.
Expand Down
Loading