argent-native-profiler

1. Tools

• native-profiler-start: start profiling on a booted device. iOS: xctrace recording for CPU, hangs, and leaks.
• native-profiler-stop: stop the profiler and export trace data to timestamped XML files.
• native-profiler-analyze: parse exported trace data and return a structured bottleneck payload.
• profiler-stack-query: drill into parsed data: hang stacks, function callers, thread breakdown, leak details.
• profiler-load: list and reload previous trace sessions from disk for re-investigation.
• Physical iPhone: not supported; use a simulator.

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2. Platform Support

• iOS: Backend: Xcode Instruments via xctrace on a booted simulator or connected device. Requires Xcode command-line tools on PATH. Surfaces CPU hotspots, UI hangs, and memory leaks (instruments Leaks table).
• Android: Backend: Perfetto via adb shell perfetto + an in-process WASM trace-processor engine. Surfaces CPU hotspots and UI hangs, with per-hang jank reason codes, a main-thread state breakdown with blocked_function attribution, and a GC overlap annotation. Also reports an RSS-growth signal for memory pressure; treat it as a hint to confirm manually, not a confirmed leak. The target app must be debuggable or include <profileable android:shell="true"/> in its manifest for perf_sample callstacks to be captured.

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3. Investigation Patterns