Project 4: Implement a Thread-Safe Queue (Arc + Mutex)

A thread-safe bounded queue using Arc<Mutex<VecDeque<T>>> that multiple threads can safely push to and pop from.

Quick Reference

Attribute Value
Primary Language Rust
Alternative Languages None
Difficulty Level 3: Advanced
Time Estimate 1 week
Knowledge Area Concurrency / Synchronization
Tooling Rust std::sync
Prerequisites Projects 1-3, basic concurrency understanding

What You Will Build

A thread-safe bounded queue using Arc<Mutex<VecDeque<T>>> that multiple threads can safely push to and pop from.

Why It Matters

This project builds core skills that appear repeatedly in real-world systems and tooling.

Core Challenges

  • Sharing queue across threads → maps to Arc for shared ownership
  • Preventing data races → maps to Mutex for synchronized access
  • Handling blocking semantics → maps to Condvar for thread coordination
  • Avoiding deadlocks → maps to understanding lock ordering

Key Concepts

  • Concurrency Primitives: “The Rust Programming Language” Chapter 16
  • Arc and Mutex: “Programming Rust” Chapter 19
  • Lock-Free Programming: “Rust Atomics and Locks” by Mara Bos
  • Producer-Consumer Pattern: Any concurrency textbook

Real-World Outcome

Deliver a working demo with observable output that proves the feature is correct.

Implementation Guide

  1. Reproduce the simplest happy-path scenario.
  2. Build the smallest working version of the core feature.
  3. Add input validation and error handling.
  4. Add instrumentation/logging to confirm behavior.
  5. Refactor into clean modules with tests.

Milestones

  • Milestone 1: Minimal working program that runs end-to-end.
  • Milestone 2: Correct outputs for typical inputs.
  • Milestone 3: Robust handling of edge cases.
  • Milestone 4: Clean structure and documented usage.

Validation Checklist

  • Output matches the real-world outcome example
  • Handles invalid inputs safely
  • Provides clear errors and exit codes
  • Repeatable results across runs

References

  • Main guide: RUST_BORROW_CHECKER_LIFETIME_PHILOSOPHY.md
  • “Rust Atomics and Locks” by Mara Bos