KRKrisso·Apr 25, 2026Submission
Show HN: Xtrace – Unix-Style macOS Profiling for Instruments (CPU/GPU/Memory)
I built this because I wanted a terminal-first profiling workflow on macOS, without constantly switching into the Instruments GUI.
What it does today:
- CPU analysis: summary, timeline, calltree, collapsed stacks, flamegraph, diff
- GPU analysis (trace-gpu.py): active/idle ratios, command-buffer cadence, process ownership
- Memory analysis (trace-memory.py): summary, leaks, growth, heap/regions
- Recording modes: launch, attach by PID/name, wait-for spawn, system-wide
- Root-aware attach flow for protected/root-owned processes
- JSON output for automation/LLM workflows (I use it in autoresearch loops: hypothesis → experiment → keep/discard)
Other notes:
- macOS only (Instruments/xctrace)
- core analysis is Python stdlib (no pip deps)
- optional tools: speedscope + inferno for best visualization
Would love feedback on workflow, rough edges
Read the rest
, and what integrations would make this more useful.