perf(allocator): increase initial chunk size from 512B to 16KB#20968
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Pull request overview
Reapplies previously-lost allocator performance tweaks to oxc_allocator’s bump arena by increasing the default initial chunk size and ensuring with_capacity honors small requested capacities, with updated allocation-tracking snapshots.
Changes:
- Increase the initial arena chunk target (
FIRST_ALLOCATION_GOAL) from 512B to 16KiB to reduce allocator calls. - Update
try_with_min_align_and_capacitysoBump::with_capacity(n)doesn’t allocate the new 16KiB default whennis much smaller. - Refresh internal allocator test expectations and memory-allocation tracking snapshots to match the new behavior.
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.
| File | Description |
|---|---|
| crates/oxc_allocator/src/bump.rs | Adjusts first-chunk sizing behavior and updates a unit test to reflect deferred allocation on Bump::new(). |
| tasks/track_memory_allocations/allocs_semantic.snap | Updates expected allocation counts for semantic tracking after allocator behavior change. |
| tasks/track_memory_allocations/allocs_minifier.snap | Updates expected allocation counts for minifier tracking after allocator behavior change. |
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Repeat of #18234. #20963 wiped all changes to `bump.rs`, going back to a fresh copy of `bumpalo`. Re-apply changes from #18234 which were lost in the process - increasing default arena chunk size to 16 KiB, and altering `try_with_min_align_and_capacity` to respect the requested capacity in `Bump::with_capacity`. Add a comment to `try_with_min_align_and_capacity` explaining why that change is required.
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### 🐛 Bug Fixes - fc7f60c allocator: Revert changes to `get_current_chunk_footer_field_offset` (#20964) (overlookmotel) - 31316c8 semantic: Rebind class expressions before identifier checks (#20916) (camc314) ### ⚡ Performance - fb52383 napi/parser, linter/plugins: Clear buffers and source texts earlier (#21025) (overlookmotel) - 3b7dec4 napi/parser, linter/plugins: Use `utf8Slice` for decoding UTF-8 strings (#21022) (overlookmotel) - 012c924 napi/parser, linter/plugins: Speed up decoding strings in raw transfer (#21021) (overlookmotel) - 55e1e9b napi/parser, linter/plugins: Initialize vars as 0 (#21020) (overlookmotel) - c25ef02 napi/parser, linter/plugins: Simplify branch condition in `deserializeStr` (#21019) (overlookmotel) - 9f494c3 napi/parser, linter/plugins: Raw transfer use `String.fromCharCode` in string decoding (#21018) (overlookmotel) - 91cf105 allocator: Increase initial chunk size from 512B to 16KB (#20968) (overlookmotel) - cbc0c21 allocator: Add `#[cold]` to to error handling functions (#20967) (overlookmotel) - 0503a78 napi/parser, linter/plugins: Faster deserialization of `raw` fields (#20923) (overlookmotel) - a24f75e napi/parser: Optimize string deserialization for non-ASCII sources (#20834) (Joshua Tuddenham) ### 📚 Documentation - c78a57a syntax: Fix typo (#21044) (camc314) - f5e228f allocator: Fix typo in comment (#20972) (overlookmotel) - 7159d51 allocator: Improve doc comment examples for `vec2::Vec` (#20969) (overlookmotel) - b1da750 allocator, data_structures: Correct comments (#20966) (overlookmotel) Co-authored-by: Boshen <1430279+Boshen@users.noreply.github.com>
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Repeat of #18234.
#20963 wiped all changes to
bump.rs, going back to a fresh copy ofbumpalo.Re-apply changes from #18234 which were lost in the process - increasing default arena chunk size to 16 KiB, and altering
try_with_min_align_and_capacityto respect the requested capacity inBump::with_capacity.Add a comment to
try_with_min_align_and_capacityexplaining why that change is required.