Silimon

A lightweight macOS menu bar app for monitoring Apple Silicon performance metrics.

Why Silimon?

A simple, lightweight menu bar app that shows Apple Silicon metrics at a glance - no sudo, no bloat, no subscription.

Features

• Real-time power monitoring - CPU, GPU, and ANE power consumption in watts
• CPU cluster frequencies - E-core and P-core frequencies in MHz
• GPU utilization - Active usage percentage and frequency
• Memory pressure - Used memory, pressure state, and swap
• Network throughput - Download and upload speeds
• Thermal state - Current thermal pressure level
• History charts - Sparkline trends for all metrics with configurable duration
• Menu bar graph mode - Compact sparkline view with adjustable width
• Customizable colors - Pick colors for each metric from a curated palette
• No sudo required - Uses IOReport API for direct access to SoC metrics

Installation

# Install via Homebrew
brew tap odfalik/silimon
brew install silimon

# Start silimon
silimon

Click the menu bar icon to view metrics. Use the gear icon for settings (sampling rate, launch at login, etc.).

Build from Source

git clone https://github.com/odfalik/silimon.git
cd silimon
make install
silimon

Requirements

• macOS 13.0 (Ventura) or later
• Apple Silicon Mac (M1, M2, M3, M4, etc.)
• Xcode 14.0+ (for building from source)

How It Works

Silimon uses Apple's IOReport API for low-level SoC telemetry. This provides:

• CPU cluster frequencies (E-core and P-core)
• Per-component power consumption (CPU, GPU, ANE, DRAM)
• GPU frequency and utilization
• Thermal state

Memory metrics use the Mach kernel API (no special permissions required).

Unlike tools that use powermetrics, Silimon accesses IOReport directly without requiring sudo, making it ideal for a menu bar app.

Troubleshooting

If metrics aren't showing correctly, open Settings (gear icon) and click Diagnose to run system diagnostics. This will check:

• macOS version and architecture compatibility
• IOReport API availability (for power metrics)
• System command availability (vm_stat, memory_pressure)
• Network interface and battery access

You can copy the diagnostic report to include in bug reports.

Uninstall

brew uninstall silimon
rm ~/Library/LaunchAgents/com.silimon.app.plist  # if launch at login was enabled

Development

make build      # Build
make dev        # Run in development mode
make release    # Build release version
make clean      # Clean build artifacts

See CONTRIBUTING.md for testing and contribution guidelines.

License

MIT License - see LICENSE for details.

Credits

• Inspired by asitop - the original Apple Silicon performance monitor
• IOReport implementation based on mactop - a Go-based macOS system monitor