feat(track-memory-allocations): track heap deallocs, alloc bytes, and peak growth#24619
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… peak growth (#24619) Adds three heap-side metrics to the allocation snapshots, using the metric machinery from #24587: - `sys deallocs` (exact count) — system deallocations per stage; read against `sys allocs` it shows whether a stage churns or retains heap. - `sys alloc bytes` — cumulative bytes requested from the system allocator per stage (allocation sizes plus reallocation growth). - `sys peak growth` — high-water mark of live heap during a stage relative to the live bytes at stage start, via live-bytes accounting in the `GlobalAlloc` wrapper. Captures transient heap a stage needs even when it frees it before finishing. Arena chunk operations are excluded from all `sys` metrics at the source: `oxc_allocator` marks each chunk allocation/deallocation immediately before calling the system allocator (task-only `track_allocations` feature, compiled out everywhere else), and the task's tracking allocator consumes the marker and skips the call. This replaces the previous global chunk counter + per-stage subtraction: a subtraction can correct counts but not a high-water mark, and chunk sizes are quantized and platform-dependent (whether an arena needs one more chunk depends on byte totals that vary across architectures with type layout — the #22621 mechanism). The first CI run demonstrated this concretely: kitchen-sink's minifier peak differed deterministically by 720 kB between aarch64 and x86_64 because the mangler's temporary arena crossed a chunk-growth boundary only on x86_64; and antd's formatter "peak" was 762 MB of main-arena chunk-doubling history rather than formatter behavior (now 13.8 MB of actual heap use). Cross-platform tolerances: the cumulative byte metrics still drift with the number of heap hashbrown tables allocated (their control-group width is architecture-dependent), so they use a relative tolerance (1%, 4 kB floor) via the committed-value comparison from #24565; `arena size` keeps its tight 1024-byte tolerance. Sample values for checker.ts (2.9 MB source): parser needs only 2.4 kB of transient heap (fully arena-based), semantic peaks at 3.9 MB, the minifier is the pipeline's largest heap consumer at 10.2 MB, and the formatter requests 5.9 MB total while peaking at 3 MB (heavy alloc/free churn). 🤖 Implemented with [Claude Code](https://claude.com/claude-code).
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### 💥 BREAKING CHANGES - 54cc121 ast: [**BREAKING**] Split `MetaProperty` into `ImportMeta` and `NewTarget` (#24557) (camc314) ### 🚀 Features - 4c71560 parser: More friendly error for spread element in dynamic imports (#24705) (sapphi-red) - 7b045cd minfier: Drop last break from last switch case (#24673) (Armano) - 7d3c178 minifier: Remove unreachable recursive functions (#24125) (Dunqing) - 94f99b3 ast: Allow `NONE` to be passed to AST builder methods where `Option<ArenaVec>` is expected (#24629) (overlookmotel) - 77230c5 ast: Accept arrays for `ArenaVec` params of AST builder methods (#24621) (overlookmotel) - f08b152 allocator: Implement `FromIn` for array to `Vec` conversion (#24620) (overlookmotel) - 2338c13 track-memory-allocations: Track heap deallocs, alloc bytes, and peak growth (#24619) (Boshen) - 7aa4739 syntax,transformer: Move JSX entity decoder to `oxc_syntax` (#24617) (camc314) - 2b097c4 str: Export `Str` as `ArenaStr` (#24604) (overlookmotel) - 3acf4c1 minifier: Expand switch optimiation to remove empty cases (#24520) (Armano) - 129b759 parser: Improve diagnostics for unparenthesized LHS on exponential expr (#24569) (camc314) - 4d0c601 minifier: Fold arithmetic over undefined and null operands (#24485) (Dunqing) - 91541dd minifier: Drop empty switch statements (#24527) (Armano) - d05224d ast_visit: Generate VisitJs visitor that skips TypeScript type-space (#24499) (Boshen) - 3d22307 parser: Add `ParseOptions::enable_ident_hashes` (#24491) (Boshen) ### 🐛 Bug Fixes - 64c2241 minifier: Align class heritage removal with assumptions (#24533) (Dunqing) - 48b59f4 parser: Span ambient generator diagnostics (#24711) (camc314) - e750a82 ecmascript: Fix false negative for may_have_side_effects on dynamic property access (#24709) (sapphi-red) - f145d73 minifier: Guard reordered identifier reads (#24698) (Dunqing) - a2ef382 isolated-declarations: Reject `window.Symbol` as global symbol reference (#24689) (camc314) - b1bcf72 minifier: Invalidate facts for redeclared bindings (#24658) (Dunqing) - 921b834 minifier: Don't treat a conditionally-assigned var as write-once (#24650) (Dunqing) - 061af1f minifier: Avoid stale pure function summaries (#24636) (Dunqing) - 40c2f43 allocator: `Vec::from_array_in` do not allocate zero-length array (#24628) (overlookmotel) - 70994ae codegen: Preserve comments before expression operands (#24510) (Dunqing) - 7b4baff parser: Reject new import member access (#23459) (camc314) - 128b385 minifier: Clippy warning with no-debug-assertions (#24547) (camc314) - 8421feb parser: Use first `as` span for imported name (#24537) (leaysgur) - c517aa0 parser: Reject invalid accessor assertions (#24504) (camc314) ### ⚡ Performance - 884d9eb parser: Pre-size cover-grammar assignment target buffers (#24683) (Boshen) - d3f07a0 diagnostics: Box OxcDiagnosticInner to reduce binary size (#24665) (Boshen) - bcc9de0 parser: Defer diagnostic creation until parse exit (#24663) (Boshen) - c35d8ab allocator: Mark `ReplaceWith` panic path cold (#24515) (camc314) - ba65790 semantic, allocator: Branchless `clone_in` for semantic IDs (#24564) (overlookmotel) - 747feec parser: Build AST nodes with the AST builder instead of cloning (#24540) (Boshen) - ba35a0d react_compiler: Use IndexVec for dense id-keyed maps (#24549) (Boshen) - b685062 react_compiler: Keep small hot-path collections inline (#24514) (Marius Schulz) - a149e95 transformer: Outline rare expression exits (#24512) (camc314) - 7808a6e react_compiler: Make aliasing effects cheap to intern and clone (#24506) (Marius Schulz) - 3a36f2a react_compiler: Store AbstractValue reasons as a u16 bitmask (#24480) (Boshen) - 1c96753 react_compiler: Use FxHashMap for the lookup-only aliasing node map (#24490) (Boshen) Co-authored-by: Cameron <[email protected]>
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Adds three heap-side metrics to the allocation snapshots, using the metric machinery from #24587:
sys deallocs(exact count) — system deallocations per stage; read againstsys allocsit shows whether a stage churns or retains heap.sys alloc bytes— cumulative bytes requested from the system allocator per stage (allocation sizes plus reallocation growth).sys peak growth— high-water mark of live heap during a stage relative to the live bytes at stage start, via live-bytes accounting in theGlobalAllocwrapper. Captures transient heap a stage needs even when it frees it before finishing.Arena chunk operations are excluded from all
sysmetrics at the source:oxc_allocatormarks each chunk allocation/deallocation immediately before calling the system allocator (task-onlytrack_allocationsfeature, compiled out everywhere else), and the task's tracking allocator consumes the marker and skips the call. This replaces the previous global chunk counter + per-stage subtraction: a subtraction can correct counts but not a high-water mark, and chunk sizes are quantized and platform-dependent (whether an arena needs one more chunk depends on byte totals that vary across architectures with type layout — the #22621 mechanism). The first CI run demonstrated this concretely: kitchen-sink's minifier peak differed deterministically by 720 kB between aarch64 and x86_64 because the mangler's temporary arena crossed a chunk-growth boundary only on x86_64; and antd's formatter "peak" was 762 MB of main-arena chunk-doubling history rather than formatter behavior (now 13.8 MB of actual heap use).Cross-platform tolerances: the cumulative byte metrics still drift with the number of heap hashbrown tables allocated (their control-group width is architecture-dependent), so they use a relative tolerance (1%, 4 kB floor) via the committed-value comparison from #24565;
arena sizekeeps its tight 1024-byte tolerance.Sample values for checker.ts (2.9 MB source): parser needs only 2.4 kB of transient heap (fully arena-based), semantic peaks at 3.9 MB, the minifier is the pipeline's largest heap consumer at 10.2 MB, and the formatter requests 5.9 MB total while peaking at 3 MB (heavy alloc/free churn).
🤖 Implemented with Claude Code.