iStress

A high-performance CLI tool for stress testing Apple Silicon MacBook CPUs and GPUs, built with Rust using test-driven development.

Features

• CPU Stress Testing: Multi-threaded prime number calculation workload
• GPU Stress Testing: Metal compute shaders for intensive GPU workload
• Real-time Metrics: Live monitoring of temperature, clock speed, and power consumption
• Interactive TUI: Beautiful terminal interface with smooth line graphs showing temperature trends
• Visual Graphs: Bold, connected line graphs with labeled X/Y axes for easy reading
• Auto-scaling: Y-axis automatically scales to data range for optimal visibility
• Configurable: Control core count, test duration, and workload types via CLI flags
• Fully Tested: Built with TDD, 38 passing tests

Requirements

• macOS with Apple Silicon (M1, M2, M3, etc.)
• Rust toolchain (latest stable)

Installation

cargo build --release

The binary will be available at ./target/release/istress

Usage

Basic Examples

Run CPU stress test:

istress --cpu

Run GPU stress test:

istress --gpu

Run both CPU and GPU stress tests:

istress --cpu --gpu

Advanced Options

Specify number of CPU cores:

istress --cpu --cores 4

Set test duration:

istress --cpu --duration 60s    # 60 seconds
istress --cpu --duration 5m     # 5 minutes
istress --cpu --duration 1h     # 1 hour

Combined example:

istress --cpu --gpu --cores 8 --duration 2m

Generate a final report:

istress --cpu --gpu --duration 1m --report

CLI Flags

• --cpu: Enable CPU stress test
• --gpu: Enable GPU stress test
• --cores <N>: Number of CPU cores to use (default: all available)
• --duration <TIME>: Duration of stress test (e.g., 60s, 5m, 1h)
• --report: Print a summary report after the test completes
• --help: Show help information

Interactive Controls

• Press q to quit the stress test

Architecture

The project is organized into modular components:

• CLI Module (src/cli/mod.rs): Command-line argument parsing with clap
• CPU Module (src/cpu/mod.rs): CPU stress testing with prime number calculations
• GPU Module (src/gpu/mod.rs): GPU stress testing with Metal compute shaders
• Metrics Module (src/metrics/mod.rs): System metrics collection via IOKit FFI
• UI Module (src/ui/mod.rs): Terminal UI with ratatui for real-time visualization
• Main (src/main.rs): Orchestration and coordination of all components

Development

Running Tests

Run all tests:

cargo test

Run tests for a specific module:

cargo test --lib cli::tests
cargo test --lib cpu::tests
cargo test --lib gpu::tests
cargo test --lib metrics::tests
cargo test --lib ui::tests

Building

Debug build:

cargo build

Release build (optimized):

cargo build --release

Technical Details

CPU Stress Test

• Uses rayon for parallel processing
• Implements efficient prime number calculation algorithm
• Configurable core count
• Tracks total primes found

GPU Stress Test

• Metal compute shaders with intensive math operations
• 1M float buffer processing
• Trigonometric and arithmetic operations per iteration
• Tracks completed iterations

Metrics Collection

• Direct IOKit framework integration via FFI
• Collects CPU/GPU temperature (peak, average, current)
• Collects CPU/GPU utilization percentage
• Monitors clock frequencies
• Tracks power consumption
• Tracks memory usage
• Detects thermal throttling
• Mock implementations for testing

Final Report

• Optional summary report with --report flag
• Shows peak, average, and final temperatures
• Displays CPU/GPU utilization and frequencies
• Reports workload statistics (primes/second, iterations/second)
• Indicates thermal throttling events
• Shows memory usage statistics

UI

• Real-time terminal interface with ratatui
• Live temperature graphs (CPU and GPU)
• Metrics display (temperature, frequency, power)
• Workload statistics (primes found, GPU iterations)
• 500ms refresh rate

License

This project was created as a learning exercise in Rust, TDD, and systems programming.

Contributing

This is a personal project, but feel free to fork and modify for your own use!

Safety Notes

Stress testing can:

• Generate significant heat
• Consume substantial power
• Potentially reduce battery life during extended tests
• Cause thermal throttling on sustained loads

Use responsibly and monitor your system temperatures.