dennisonbertram performance-check
Captures a point-in-time performance snapshot on macOS.
When to invoke
Trigger on phrases like: "check performance", "mac is slow", "why is my mac slow", "cpu usage", "memory pressure", "what's slowing me down".
What to check
1. Load averages — sysctl -n vm.loadavg or uptime. Compare 1-minute load to sysctl -n hw.ncpu.
- load / ncpu < 0.7:
ok - 0.7–1.0:
info - 1.0–2.0:
warn 2.0:
critical
2. Memory pressure — vm_stat (pages free / active / inactive / speculative / wired). Compute pressure ratio: (free + inactive) / total.
20% free+inactive:
ok- 10–20%:
info - 5–10%:
warn - <5%:
critical
Also parse memory_pressure output when available (memory_pressure 2>/dev/null | tail -5).
3. Swap usage — sysctl vm.swapusage. Parse "used = X.XXM".
- used = 0:
ok - used < 512 MB:
info - 512 MB – 2 GB:
warn 2 GB:
critical
4. Top 10 CPU consumers — top -l 1 -n 10 -o cpu -stats pid,command,cpu,mem. Record rows.
5. Top 10 memory consumers — top -l 1 -n 10 -o mem -stats pid,command,cpu,mem. Record rows.
6. Thermal state — pmset -g therm 2>/dev/null. Non-zero CPU_Speed_Limit = warn with the value.
7. Battery status (laptops only) — pmset -g batt. Parse percentage, AC Power/Battery Power, charging state. Low percentage on battery with no charger: info.
8. Battery health (laptops only) — ioreg -rc AppleSmartBattery 2>/dev/null. Extract CycleCount, MaxCapacity, DesignCapacity, AppleRawMaxCapacity. Compute MaxCapacity/DesignCapacity × 100:
- ≥ 85%:
ok - 75–85%:
info - 60–75%:
warn - < 60%:
criticalSkip gracefully on desktops.
9. Power summary — system_profiler SPPowerDataType 2>/dev/null | head -60 in raw.
10. Uptime — uptime. Uptime > 14 days: info "Consider rebooting; uptime N days."
Output contract
Standard envelope. Write to ~/.mac-guardian/data/performance-check-<ISOdate>.json.
Summary example: "Load 1.32 / 10, 18% memory free, swap 0.0 MB, battery health 92%."
Handoff
- On direct invocation:
bash ${CLAUDE_PLUGIN_ROOT}/scripts/render-single.sh performance-check. - When invoked by
daily-health-report, return JSON path only.
Safety
- Read-only. Do not kill processes. Do not change pmset settings.
- No
sudo.